WO2020058168A1

WO2020058168A1 - Securing resume and re-establishment of wireless connections

Info

Publication number: WO2020058168A1
Application number: PCT/EP2019/074657
Authority: WO
Inventors: Oscar Ohlsson; Prajwol Kumar NAKARMI
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2018-09-17
Filing date: 2019-09-16
Publication date: 2020-03-26

Abstract

A method is performed by a wireless device in a wireless network. The method includes determining a security token to provide in a request associated with a radio resource control (RRC) connection. A first procedure is used to determine the security token if the request is an RRC Resume Request. A second procedure is used to determine the security token if the request is an RRC Re-establishment Request. The method further includes sending the request comprising the security token to a target network node in the wireless network.

Description

SECURING RESUME AND RE-ESTABLISHMENT OF WIRELESS CONNECTIONS

TECHNICAL FIELD

Certain embodiments of the present disclosure relate, in general, to wireless communications and, more particularly, to securing wireless communications.

BACKGROUND

Radio Resource Control (RRC) connection resume and RRC connection re-establishment are two procedures which enable terminal wireless devices, e.g., user equipment (UE), to quickly restore the connection to the network by re-using the configuration from the previous connection. By re-using the previous configuration, the UE and the network avoid having to send certain signaling that would otherwise be required for connection establishment, such as certain signaling required for security activation and bearer establishment.

RRC connection resume

RRC connection resume is used by UEs in RRC inactive state to resume an RRC connection that was previously suspended. The radio access network (RAN) can choose to suspend an RRC connection and move the UE from RRC connected state to RRC inactive state, for example, after a long time of inactivity. When an RRC connection is suspended, both the UE and the RAN store the UE context and the associated identifier (a radio network temporary identifier called I-RNTI). The UE context contains the current radio configuration and includes information such as the UE security configuration, configured radio bearers, etc.

To resume an RRC connection, the UE sends an RRC resume request to the base station (e.g., a next generation NodeB network node (gNB)) with which the UE is attempting to resume the connection. FIGURE 1 illustrates an example signaling diagram of the process of resuming the RRC connection, according to certain embodiments. The UE may attempt to resume the connection with the same ccll/gNB where the connection was suspended or a different cell/gNB. The RRC resume request includes the following information

• The I-RNTI which is used to identify the UE context;

• A security token (named“resumeMAC-I” in the 3GPP specification) which is used to identify and verify the UE at RRC connection resume; and

• An indication of the cause of the resume, e.g., mobile originated data The gNB that serves the cell in which the UE is resuming is sometimes referred to as the target gNB, while the gNB serving the cell in which the UE was suspended in is sometimes referred to as the source gNB. To resume the connection, the target gNB determines which gNB is the source gNB (considering the gNB part of the I-RNTI) and requests the source gNB to send the UE’s context. The request from the target gNB to the source gNB includes, among other things, the UE ID and security token received from the UE.

The source gNB then locates the UE context based on the I-RNTI and verifies the request based on the security token (see below for further description of the security token). If successful, the source gNB forwards the UE context to the target gNB, which then responds to the UE with RRC resume to confirm the connection is being resumed. Finally, the UE acknowledges the reception of the RRC resume by sending RRC resume complete.

RRC connection re-establishment

In 5G New Radio (NR), if the UE’s link to the network becomes poor, the UE triggers a Radio Link Failure (RLF) procedure. The link can be considered poor for example if the perceived downlink quality is lower than a threshold, if a random access-procedure is unsuccessful, if the number of radio link control (RLC) retransmissions exceeds/meets a threshold, etc. When RLF is triggered, given certain conditions, the UE may attempt to re-establish the connection to the network. The UE may also attempt to reestablish the connection to the network if, for example, a handover fails, etc.

FIGURE 2 illustrates an example signaling diagram of the process of re-establishing the connection, according to certain embodiments. When the UE attempts to re-establish the connection to the network, the UE sends a re-establishment request to the gNB with which the UE is attempting to re-establish the connection. The UE may attempt to re-establish the connection with the same cell/gNB where the connection failed or a different ccll/gNB. The re-establishment request includes the following information:

• A UE ID (including the cell radio network temporary identifier, C-RNTI, and physical cell identity, PCI) used to identify the UE context;

• A security token (named“shortMAC-I” in the 3GPP specification) which is used to identify and verify the UE at RRC connection re-establishment; and

• An indication of the cause of the re-establishment, e.g., handover failure, etc.

The gNB that serves the cell that receives this request is sometimes referred to as the target gNB, while the gNB to which the UE was connected before the failure is sometimes referred to as the source gNB. The target gNB would, based on the information provided by the UE, attempt to re-establish the connection. The target gNB can do this by determining which gNB is the source gNB (considering the PCI part of the UE ID), and request the source gNB to send the UE’s context. The request from the target gNB to the source gNB includes, among other things, the UE ID and security token received from the UE.

The source gNB then locates the UE context based on the UE ID and verifies the request based on the security token (the security token is further described below). If successful, the source gNB forwards the UE context to the target gNB, which then responds to the UE with RRC re- establishment to confirm the connection is being re-established. Finally, the UE acknowledges the reception of the RRC re-establishment by sending RRC re-establishment complete.

Security token calculation for RRC connection resume and RRC connection re-establishment

The security token included in the RRC resume request or RRC re-establishment allows the network to identify the UE and verify that the request is valid. To verify the security token, the source gNB computes the expected security token and checks that it matches the value provided by the UE.

The security token is computed using the same integrity algorithm as used by the packet data convergence protocol (PDCP) layer to integrity protect messages after access stratum (AS) security activation. The integrity algorithm may use the following input parameters (e.g., according to 3 GPP Technical Specification 33.501 vl5.l .O):

- A 128 bit integrity key named KEY (the integrity key K_RRCint derived from the source gNB key K_§NB)

- A 32 bit COUNT value

A 5 bit BEARER identity

The l-bit direction of the transmission i.e. DIRECTION

and the message itself i.e. MESSAGE

The security token may be calculated in the same way in both RRC connection resume and RRC connection re-establishment. The integrity key may be the key K_RRCint derived from the source gNB key K_gNB and the message may be an Abstract Syntax Notation One (ASN.l) encoded structure containing:

The C-RNTI of the UE in the source cell;

The Physical Cell ID (PCI) of the source cell; and

The Cell ID of the target cell SUMMARY

Certain embodiments of the present disclosure relate to discriminating between resuming and re-establishing an RRC connection.

According to an embodiment, a method is performed by a wireless device in a wireless network. The method includes determining a security token to provide in a request associated with an RRC connection. A first procedure is used to determine the security token if the request is an RRC Resume Request. A second procedure is used to determine the security token if the request is an RRC Re-establishment Request. The method further includes sending the request comprising the security token to a target network node in the wireless network.

According to another embodiment, a computer program product includes a non-transitory computer readable medium storing computer readable program code. The computer readable program code comprises program code operable to perform the above method.

According to yet another embodiment, a wireless device comprises a memory configured to store instructions and processing circuitry configured to execute the instructions. The wireless device is configured to determine a security token to provide in a request associated with an RRC connection. A first procedure is used to determine the security token if the request is an RRC Resume Request. A second procedure is used to determine the security token if the request is an RRC Re-establishment Request. The wireless device is further configured to send the request comprising the security token to a target network node in the wireless network.

In certain embodiments, the method/wireless device/computer program product may have one or more additional and/or optional features, such as one or more of the following:

In particular embodiments, the first procedure and the second procedure are different procedures using a same integrity algorithm.

In particular embodiments, the integrity algorithm generates an output based on a plurality of inputs comprising an integrity key value, a count value, a bearer identity value, a direction parameter value, and a message parameter. In some embodiments, the integrity key value is derived from a key associated with a source network node in which the RRC connection was suspended or failed.

In particular embodiments, the message parameter comprises an ASN.l encoded structure containing a C-RNTI of the wireless device in a source cell in which the RRC connection was suspended or failed, a PCI of the source cell, and a cell identifier of a target cell of the target network node to which the request is sent. In particular embodiments, the first procedure and the second procedure use the same input values to the integrity algorithm to generate an output based on the input values, and the first procedure determines the security token based on a first set of bits of the output different from a second set of bits of the output used by the second procedure to determine the security token. In some embodiments, the first procedure determines the security token based on one of a number of most significant bits of the output and the second procedure determines the security token based on a number of least significant bits of the output. Alternatively, the first procedure determines the security token based on one of a number of least significant bits of the output and the second procedure determines the security token based on a number of most significant bits of the output.

In particular embodiments, one or more input values provided by the first procedure for the integrity algorithm differ from one or more input values provided by the second procedure for the integrity algorithm. In some embodiments, the integrity key value and the message parameter input values are the same for the first procedure and the second procedure, and at least one of the count value, the bearer identity value, and the direction parameter value is different for the first procedure and the second procedure.

In particular embodiments, a third procedure is used to determine the security token if the request is not an RRC Resume Request or an RRC Re-establishment Request.

In particular embodiments, the method/wireless device/computer program product further include receiving a response from the target network node. The response indicates that the security token has been successfully verified. The method/wireless device/computer program product further includes completing the RRC connection based on the response.

According to an embodiment, a method is performed by a network node in a wireless network. The method includes receiving a request associated with an RRC connection from a wireless device. The request comprises a security token. The method further includes determining whether the security token received in the request matches an expected security token based on a type of the request. The method further includes sending a response to the wireless device. The response depends on whether the security token received in the request matches the expected security token.

According to another embodiment, a computer program product includes a non-transitory computer readable medium storing computer readable program code. The computer readable program code comprises program code operable to perform the method immediately above.

According to another embodiment, a network node comprises a memory configured to store instructions and processing circuitry configured to execute the instructions. The network node is configured to receive a request associated with an RRC connection from a wireless device. The request comprises a security token. The network node is further configured to determine whether the security token received in the request matches an expected security token based on a type of the request. The network node is further configured to send a response to the wireless device. The response depends on whether the security token received in the request matches the expected security token.

In certain embodiments, the method/network node/computer program product may have one or more additional and/or optional features, such as one or more of the following:

In particular embodiments, the response indicates that the security token matches the expected security token and the method/network node/computer program product further includes receiving a message from the wireless device that completes the RRC connection.

In particular embodiments, the response comprises a rejection indicating that the security token received in the request does not match the expected security token.

In particular embodiments, the expected security token is based on a first procedure if the request is of an RRC Resume Request and a second procedure if the request is an RRC Re- establishment Request. The first procedure and the second procedure are different procedures using a same integrity algorithm. The integrity algorithm generates an output based on a plurality of inputs comprising an integrity key value, a count value, a bearer identity value, a direction parameter value, and a message parameter. In some embodiments, the integrity key value is derived from a key associated with a source network node in which the RRC connection was suspended or failed.

In particular, the first procedure and the second procedure use the same input values to the integrity algorithm to generate the output based on the input values. The first procedure determines the security token based on a first set of bits of the output different from a second set of bits of the output used by the second procedure to determine the security token.

In particular embodiments, the integrity key value and the message parameter input values are the same for the first procedure and the second procedure. At least one of the count value, the bearer identity value, and the direction parameter value is different for the first procedure and the second procedure.

Certain embodiments may provide one or more of the following technical advantages. For example, certain embodiments provide security compartmentalization by generating security tokens for the resume procedure that cannot be used in the re-establishment procedure, or vice versa. This may prevent attackers from performing a resume procedure using a security token generated by a legitimate UE for the re-establishment procedure, or vice versa. As another example, certain embodiments provide the different security tokens without requiring changes to the ASN.l encoded message used in such procedures. As yet another example, different security tokens may be generated for each procedure without using an explicit discrimination indicator in the message input to the integrity algorithm. In this manner, the security tokens, and thereby the RRC resume and RRC re-establishment requests, may be differentiated by the network.

Certain embodiments may have one or more of the technical advantages. Certain embodiments may have none, some, or all of the above-recited advantages. Other advantages may be readily apparent to one having skill in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the disclosed embodiments and their features and advantages, reference is now made to the following description, taking in conjunction with the accompanying drawings, in which:

FIGURE 1 illustrates an example signaling diagram of a process of resuming an RRC connection, according to certain embodiments;

FIGURE 2 illustrates an example signaling diagram of a process of re-establishing an RRC connection, according to certain embodiments;

FIGURE 3 illustrates an example wireless network, in accordance with certain embodiments;

FIGURE 4 illustrates an example user equipment, in accordance with certain embodiments;

FIGURE 5 illustrates an example virtualization environment, in accordance with certain embodiments;

FIGURE 6 illustrate an example telecommunication network connected via an intermediate network to a host computer, in accordance with certain embodiments;

FIGURE 7 illustrates an example host computer communicating via a base station with a user equipment over a partially wireless connection, in accordance with certain embodiments;

FIGURE 8 is a flowchart illustrating an example method implemented in a communication system, in accordance certain embodiments;

FIGURE 9 is a flowchart illustrating an example method implemented in a communication system, in accordance with certain embodiments; FIGURE 10 is a flowchart illustrating an example method implemented in a communication system, in accordance with certain embodiments;

FIGURE 11 is a flowchart illustrating an example method implemented in a communication system, in accordance with certain embodiments;

FIGURE 12 illustrates an example method performed by a wireless device, in accordance with certain embodiments;

FIGURE 13 illustrates an example method performed by a network node, in accordance with certain embodiments;

FIGURE 14 illustrates a schematic block diagram of an example apparatus in a wireless network, in accordance with certain embodiments;

FIGURE 15 illustrates an example method performed by a wireless device, in accordance with certain embodiments; and

FIGURE 16 illustrates an example method performed by a network node, in accordance with certain embodiments.

DETAILED DESCRIPTION

Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Other embodiments, however, are contained within the scope of the subject matter disclosed herein, the disclosed subject matter should not be construed as limited to only the embodiments set forth herein; rather, these embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

Generally, all terms used herein are to be interpreted according to their ordinary meaning in the relevant technical field, unless a different meaning is clearly given and/or is implied from the context in which it is used. All references to a/an/the element, apparatus, component, means, step, etc. are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. The steps of any methods disclosed herein do not have to be performed in the exact order disclosed, unless a step is explicitly described as following or preceding another step and/or where it is implicit that a step must follow or precede another step. Any feature of any of the embodiments disclosed herein may be applied to any other embodiment, wherever appropriate. Likewise, any advantage of any of the embodiments may apply to any other embodiments, and vice versa. Other objectives, features, and advantages of the enclosed embodiments will be apparent from the following description. In LTE, the message used for the security token calculation in RRC resume also contains a resume discriminator to ensure that the same message, and hence also the same security token, is not used in both RRC connection resume and RRC connection re-establishment. In contrast, in NR however, it has been agreed to remove this discriminator. Accordingly, in some embodiments, there may not be an explicit discriminator in the security token calculation to enable the discrimination between an RRC connection resume and an RRC connection re-establishment request.

The output of the integrity algorithm is 32 bit MAC. However, only the 16 least significant bits of the MAC is used for the security token due to the strict size limitation of the RRC resume request and RRC re-establishment request.

In contrast to when integrity protection is performed in the PDCP layer, the remaining input parameters (e.g., COUNT, BEARER and DIRECTION) may have no direct significance for the security token generation. In some embodiments, each of these parameters is set to the all- ones bit string. Accordingly, if these parameters are non-discriminatory and the other parameters do not indicate whether the request is a resume or re-establishment request, the security token may be indistinguishable for both types of requests using the same integrity algorithm.

There currently exist certain challenges. A problem exists with current security token definitions for RRC connection resume and RRC connection re-establishment for at least the reason that the same security token is generated in both procedures if the source and target cell are the same. This is a potential security weakness as it allows a security token that has been generated for the request message in one of the procedures to be used also for the request message in the other procedure. The following example describes an attack where an attacker performs a resume procedure using a security token that a legitimate UE generated for a re-establishment.

1. The gNB decides to suspend a UE in RRC connected state and therefore sends a suspend message.

2. The attacker blocks the suspend message from reaching the UE and at the same time acknowledges the reception of the suspend message at lower layers (i.e. below RRC) towards the gNB, thereby fooling the gNB into believe the UE has entered RRC inactive state.

3. The blocking of the suspend message will cause the UE to declare RLF and trigger RRC connection re-establishment and the attacker will then intercept the security token in the RRC re-establishment request.

4. Assuming the attacker can determine the I-RNTI of the UE (e.g., because it is assigned in a predictable manner or because the UE identifying part of the I-RNTI is short enough so that it can be guessed), the attacker can send an RRC resume request to the gNB with the intercepted security token which the gNB will accept since the security token is the same in both the resume and re-establishment procedure.

To recover from this situation, the UE may detect a state mismatch (e.g., in response to a timer expiry) and trigger a recovery procedure to resolve the state mismatch. However, Attacks like the one above are effectively denial-of-service attacks as the state mismatch between the UE and network causes the UE to become unreachable. It is possible that more severe attacks of this type will arise in the future as the resume and re-establishment procedures evolve. Thus, from a security perspective it is preferred if different security tokens are used for resume and re- establishment.

Certain aspects of the present disclosure and their embodiments may provide solutions to these or other challenges. For example, certain embodiments provide security compartmentalization, which ensures security material (keys, tokens, etc.) generated in one context should not be possible to use in another context. As a result, certain embodiments provide a security token generated for the resume procedure that cannot be used in the re-establishment procedure, or vice versa. To this end, certain embodiments calculate the security tokens for each procedure differently.

In certain embodiments, to ensure that identical security tokens are not used in resume and re-establishment, the same approach as in LTE may be adopted and include a resume discriminator in the ASN.l encoded message over which the security token is calculated. This involves, however, ASN.l changes, which has drawbacks. Accordingly, in certain embodiments described herein, different security tokens are provided without requiring changes to the ASN.l encoded message.

According to certain embodiments, to ensure that the security token generated for the resume procedure cannot be used in the re-establishment procedure, or vice versa, the security token may be computed differently for the two procedures. In some embodiments, the generation of the security tokens does not involve any changes to the ASN.1 message which is used as input to the integrity algorithm used in the security token generation. As described in a first set of embodiments, different parts of the integrity algorithm output are used for the different security tokens. As described in a second set of embodiments, one of the other inputs to the integrity algorithm may be varied to generate different security tokens.

According to a first set of embodiments, the resume and re-establishment procedures use the same inputs to the integrity algorithm (e.g., the KEY, COUNT, BEARER, DIRECTION, MESSAGE inputs described above) but the security tokens are based on different parts of the MAC output (e.g., the 32bit MAC output). For example, in some embodiments, the 16 least significant bits of the MAC may be used for the resume security token and the 16 most significant bits may be used for the re-establishment security token, or vice versa. In some embodiments, the resume and re-establishment security tokens may use any suitable bits from the MAC output. For example, in some embodiments, the bits selected for the resume security token may partially overlap the bits selected for the re-establishment security token. For example, the resume and re- establishment tokens may share 1-15 bits from the 32 bit MAC output. In some embodiments, the overlap of bits is minimized or limited below a certain number of overlapping bits.

As a result, no changes need be made to the inputs of the integrity algorithm generating the 32 bit MAC output. Instead, the selection of the 16 bits (or number of bits used for the security token) used for the security token may be defined to create differentiated security tokens, which has one or more of the advantages described herein.

According to a second set of embodiments, the resume and re-establishment procedures vary one or more inputs used in the integrity algorithm to generate different 32bit MAC outputs and result in different security tokens. In certain embodiments, the inputs for the KEY and MESSAGE parameters in the integrity algorithm are the same for both procedures, but the inputs for at least one of the COUNT, BEARER, and DIRECTION parameters differ. For example, the any of the three parameters could each be set to the all-ones bit string in the generation of the resume token and to the all-zeros bit string in the generation of the re-establishment token. Further, the individual inputs can also be set to have different values, which may allow for the introduction of additional cases if further separation of tokens is needed. For example, if another RRC-related token is needed, then some bits (e.g., least significant or most significant bits) in the COUNT or BEARER parameters could be chosen so that these chosen bits become the differentiators.

The differentiation of the bits used for the varied parameter(s) may be defined via a standard or by the network or by a particular implementation. Other considerations may be taken into account when determining how to vary the inputs for the resume and re-establishment security tokens. For example, the sets of bits may depend on the structure or steps of the integrity algorithm. In particular, the sets of bits may be chosen to provide security tokens that have a low probability of matching or being similar above a threshold amount. In this manner, the generated security tokens may be easily identified as belonging to a resume request or a re-establishment request, e.g., at the target network node. Although the subject matter described herein may be implemented in any appropriate type of system using any suitable components, the embodiments disclosed herein are described in relation to a wireless network, such as the example wireless network illustrated in Figure 3. For simplicity, the wireless network of Figure 3 only depicts network 106, network nodes 160 and l60b, and WDs 110, 110b, and l lOc. In practice, a wireless network may further include any additional elements suitable to support communication between wireless devices or between a wireless device and another communication device, such as a landline telephone, a service provider, or any other network node or end device. Of the illustrated components, network node 160 and wireless device (WD) 110 are depicted with additional detail. The wireless network may provide communication and other types of services to one or more wireless devices to facilitate the wireless devices’ access to and/or use of the services provided by, or via, the wireless network.

The wireless network may comprise and/or interface with any type of communication, telecommunication, data, cellular, and/or radio network or other similar type of system. In some embodiments, the wireless network may be configured to operate according to specific standards or other types of predefined rules or procedures. Thus, particular embodiments of the wireless network may implement communication standards, such as Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), Long Term Evolution (LTE), and/or other suitable 2G, 3G, 4G, or 5G standards; wireless local area network (WLAN) standards, such as the IEEE 802.11 standards; and/or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave and/or ZigBee standards.

Network 106 may comprise one or more backhaul networks, core networks, IP networks, public switched telephone networks (PSTNs), packet data networks, optical networks, wide-area networks (WANs), local area networks (LANs), wireless local area networks (WLANs), wired networks, wireless networks, metropolitan area networks, and other networks to enable communication between devices.

Network node 160 and WD 110 comprise various components described in more detail below. These components work together in order to provide network node and/or wireless device functionality, such as providing wireless connections in a wireless network. In different embodiments, the wireless network may comprise any number of wired or wireless networks, network nodes, base stations, controllers, wireless devices, relay stations, and/or any other components or systems that may facilitate or participate in the communication of data and/or signals whether via wired or wireless connections. As used herein, network node refers to equipment capable, configured, arranged and/or operable to communicate directly or indirectly with a wireless device and/or with other network nodes or equipment in the wireless network to enable and/or provide wireless access to the wireless device and/or to perform other functions (e.g., administration) in the wireless network. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)). Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and may then also be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units and/or remote radio units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS). Yet further examples of network nodes include multi- standard radio (MSR) equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi-cell/multicast coordination entities (MCEs), core network nodes (e.g., MSCs, MMEs), O&M nodes, OSS nodes, SON nodes, positioning nodes (e.g., E-SMLCs), and/or MDTs. As another example, a network node may be a virtual network node as described in more detail below. More generally, however, network nodes may represent any suitable device (or group of devices) capable, configured, arranged, and/or operable to enable and/or provide a wireless device with access to the wireless network or to provide some service to a wireless device that has accessed the wireless network.

In Figure 3, network node 160 includes processing circuitry 170, device readable medium 180, interface 190, auxiliary equipment 184, power source 186, power circuitry 187, and antenna 162. Although network node 160 illustrated in the example wireless network of Figure 3 may represent a device that includes the illustrated combination of hardware components, other embodiments may comprise network nodes with different combinations of components. It is to be understood that a network node comprises any suitable combination of hardware and/or software needed to perform the tasks, features, functions and methods disclosed herein. Moreover, while the components of network node 160 are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, a network node may comprise multiple different physical components that make up a single illustrated component (e.g., device readable medium 180 may comprise multiple separate hard drives as well as multiple RAM modules).

Similarly, network node 160 may be composed of multiple physically separate components (e.g., a NodeB component and a RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components. In certain scenarios in which network node 160 comprises multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeB’s. In such a scenario, each unique NodeB and RNC pair, may in some instances be considered a single separate network node. In some embodiments, network node 160 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate device readable medium 180 for the different RATs) and some components may be reused (e.g., the same antenna 162 may be shared by the RATs). Network node 160 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 160, such as, for example, GSM, WCDMA, LTE, NR, WiFi, or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network node 160.

Processing circuitry 170 is configured to perform any determining, calculating, or similar operations (e.g., certain obtaining operations) described herein as being provided by a network node. These operations performed by processing circuitry 170 may include processing information obtained by processing circuitry 170 by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and/or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination.

Processing circuitry 170 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide, either alone or in conjunction with other network node 160 components, such as device readable medium 180, network node 160 functionality. For example, processing circuitry 170 may execute instructions stored in device readable medium 180 or in memory within processing circuitry 170. Such functionality may include providing any of the various wireless features, functions, or benefits discussed herein. In some embodiments, processing circuitry 170 may include a system on a chip (SOC).

In some embodiments, processing circuitry 170 may include one or more of radio frequency (RF) transceiver circuitry 172 and baseband processing circuitry 174. In some embodiments, radio frequency (RF) transceiver circuitry 172 and baseband processing circuitry 174 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry 172 and baseband processing circuitry 174 may be on the same chip or set of chips, boards, or units

In certain embodiments, some or all of the functionality described herein as being provided by a network node, base station, eNB or other such network device may be performed by processing circuitry 170 executing instructions stored on device readable medium 180 or memory within processing circuitry 170. In alternative embodiments, some or all of the functionality may be provided by processing circuitry 170 without executing instructions stored on a separate or discrete device readable medium, such as in a hard-wired manner. In any of those embodiments, whether executing instructions stored on a device readable storage medium or not, processing circuitry 170 can be configured to perform the described functionality. The benefits provided by such functionality are not limited to processing circuitry 170 alone or to other components of network node 160, but are enjoyed by network node 160 as a whole, and/or by end users and the wireless network generally.

Device readable medium 180 may comprise any form of volatile or non-volatile computer readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device readable and/or computer-executable memory devices that store information, data, and/or instructions that may be used by processing circuitry 170. Device readable medium 180 may store any suitable instructions, data or information, including a computer program, software, an application including one or more of logic, rules, code, tables, etc. and/or other instructions capable of being executed by processing circuitry 170 and, utilized by network node 160. Device readable medium 180 may be used to store any calculations made by processing circuitry 170 and/or any data received via interface 190. In some embodiments, processing circuitry 170 and device readable medium 180 maybe considered to be integrated. Interface 190 is used in the wired or wireless communication of signalling and/or data between network node 160, network 106, and/or WDs 110. As illustrated, interface 190 comprises port(s)/terminal(s) 194 to send and receive data, for example to and from network 106 over a wired connection. Interface 190 also includes radio front end circuitry 192 that may be coupled to, or in certain embodiments a part of, antenna 162. Radio front end circuitry 192 comprises filters 198 and amplifiers 196. Radio front end circuitry 192 may be connected to antenna 162 and processing circuitry 170. Radio front end circuitry may be configured to condition signals communicated between antenna 162 and processing circuitry 170. Radio front end circuitry 192 may receive digital data that is to be sent out to other network nodes or WDs via a wireless connection. Radio front end circuitry 192 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 198 and/or amplifiers 196. The radio signal may then be transmitted via antenna 162. Similarly, when receiving data, antenna 162 may collect radio signals which are then converted into digital data by radio front end circuitry 192. The digital data may be passed to processing circuitry 170. In other embodiments, the interface may comprise different components and/or different combinations of components.

In certain alternative embodiments, network node 160 may not include separate radio front end circuitry 192, instead, processing circuitry 170 may comprise radio front end circuitry and may be connected to antenna 162 without separate radio front end circuitry 192. Similarly, in some embodiments, all or some of RF transceiver circuitry 172 may be considered a part of interface 190. In still other embodiments, interface 190 may include one or more ports or terminals 194, radio front end circuitry 192, and RF transceiver circuitry 172, as part of a radio unit (not shown), and interface 190 may communicate with baseband processing circuitry 174, which is part of a digital unit (not shown).

Antenna 162 may include one or more antennas, or antenna arrays, configured to send and/or receive wireless signals. Antenna 162 may be coupled to radio front end circuitry 190 and may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. In some embodiments, antenna 162 may comprise one or more omni-directional, sector or panel antennas operable to transmit/receive radio signals between, for example, 2 GHz and 66 GHz. An omni-directional antenna may be used to transmit/receive radio signals in any direction, a sector antenna may be used to transmit/receive radio signals from devices within a particular area, and a panel antenna may be a line of sight antenna used to transmit/receive radio signals in a relatively straight line. In some instances, the use of more than one antenna may be referred to as MIMO. In certain embodiments, antenna 162 may be separate from network node 160 and may be connectable to network node 160 through an interface or port.

Antenna 162, interface 190, and/or processing circuitry 170 may be configured to perform any receiving operations and/or certain obtaining operations described herein as being performed by a network node. Any information, data and/or signals may be received from a wireless device, another network node and/or any other network equipment. Similarly, antenna 162, interface 190, and/or processing circuitry 170 may be configured to perform any transmitting operations described herein as being performed by a network node. Any information, data and/or signals may be transmitted to a wireless device, another network node and/or any other network equipment.

Power circuitry 187 may comprise, or be coupled to, power management circuitry and is configured to supply the components of network node 160 with power for performing the functionality described herein. Power circuitry 187 may receive power from power source 186. Power source 186 and/or power circuitry 187 may be configured to provide power to the various components of network node 160 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). Power source 186 may either be included in, or external to, power circuitry 187 and/or network node 160. For example, network node 160 may be connectable to an external power source (e.g., an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry 187. As a further example, power source 186 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry 187. The battery may provide backup power should the external power source fail. Other types of power sources, such as photovoltaic devices, may also be used.

Alternative embodiments of network node 160 may include additional components beyond those shown in Figure 3 that may be responsible for providing certain aspects of the network node’s functionality, including any of the functionality described herein and/or any functionality necessary to support the subject matter described herein. For example, network node 160 may include user interface equipment to allow input of information into network node 160 and to allow output of information from network node 160. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for network node 160.

As used herein, wireless device (WD) refers to a device capable, configured, arranged and/or operable to communicate wirelessly with network nodes and/or other wireless devices. Unless otherwise noted, the term WD may be used interchangeably herein with user equipment (UE). Communicating wirelessly may involve transmitting and/or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and/or other types of signals suitable for conveying information through air. In some embodiments, a WD may be configured to transmit and/or receive information without direct human interaction. For instance, a WD may be designed to transmit information to a network on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the network. Examples of a WD include, but are not limited to, a smart phone, a mobile phone, a cell phone, a voice over IP (VoIP) phone, a wireless local loop phone, a desktop computer, a personal digital assistant (PDA), a wireless cameras, a gaming console or device, a music storage device, a playback appliance, a wearable terminal device, a wireless endpoint, a mobile station, a tablet, a laptop, a laptop-embedded equipment (LEE), a laptop-mounted equipment (LME), a smart device, a wireless customer- premise equipment (CPE) a vehicle-mounted wireless terminal device, etc.. A WD may support device-to-device (D2D) communication, for example by implementing a 3GPP standard for sidelink communication, vehicle-to-vehicle (V2V), vehicle-to -infrastructure (V2I), vehicle-to- everything (V2X) and may in this case be referred to as a D2D communication device. As yet another specific example, in an Internet of Things (IoT) scenario, a WD may represent a machine or other device that performs monitoring and/or measurements, and transmits the results of such monitoring and/or measurements to another WD and/or a network node. The WD may in this case be a machine-to-machine (M2M) device, which may in a 3 GPP context be referred to as an MTC device. As one particular example, the WD may be a UE implementing the 3GPP narrow band internet of things (NB-IoT) standard. Particular examples of such machines or devices are sensors, metering devices such as power meters, industrial machinery, or home or personal appliances (e.g. refrigerators, televisions, etc.) personal wearables (e.g., watches, fitness trackers, etc.). In other scenarios, a WD may represent a vehicle or other equipment that is capable of monitoring and/or reporting on its operational status or other functions associated with its operation. A WD as described above may represent the endpoint of a wireless connection, in which case the device may be referred to as a wireless terminal. Furthermore, a WD as described above may be mobile, in which case it may also be referred to as a mobile device or a mobile terminal.

As illustrated, wireless device 110 includes antenna 111, interface 114, processing circuitry 120, device readable medium 130, user interface equipment 132, auxiliary equipment 134, power source 136 and power circuitry 137. WD 110 may include multiple sets of one or more of the illustrated components for different wireless technologies supported by WD 110, such as, for example, GSM, WCDMA, LTE, NR, WiFi, WiMAX, or Bluetooth wireless technologies, just to mention a few. These wireless technologies may be integrated into the same or different chips or set of chips as other components within WD 110.

Antenna 111 may include one or more antennas or antenna arrays, configured to send and/or receive wireless signals, and is connected to interface 114. In certain alternative embodiments, antenna 111 may be separate from WD 110 and be connectable to WD 110 through an interface or port. Antenna 111, interface 114, and/or processing circuitry 120 may be configured to perform any receiving or transmitting operations described herein as being performed by a WD. Any information, data and/or signals may be received from a network node and/or another WD. In some embodiments, radio front end circuitry and/or antenna 111 may be considered an interface.

As illustrated, interface 114 comprises radio front end circuitry 112 and antenna 111. Radio front end circuitry 112 comprise one or more filters 118 and amplifiers 116. Radio front end circuitry 114 is connected to antenna 111 and processing circuitry 120, and is configured to condition signals communicated between antenna 111 and processing circuitry 120. Radio front end circuitry 112 may be coupled to or a part of antenna 111. In some embodiments, WD 110 may not include separate radio front end circuitry 112; rather, processing circuitry 120 may comprise radio front end circuitry and may be connected to antenna 111. Similarly, in some embodiments, some or all of RF transceiver circuitry 122 may be considered a part of interface 114. Radio front end circuitry 112 may receive digital data that is to be sent out to other network nodes or WDs via a wireless connection. Radio front end circuitry 112 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 118 and/or amplifiers 116. The radio signal may then be transmited via antenna 111. Similarly, when receiving data, antenna 111 may collect radio signals which are then converted into digital data by radio front end circuitry 112. The digital data may be passed to processing circuitry 120. In other embodiments, the interface may comprise different components and/or different combinations of components.

Processing circuitry 120 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software, and/or encoded logic operable to provide, either alone or in conjunction with other WD 110 components, such as device readable medium 130, WD 110 functionality. Such functionality may include providing any of the various wireless features or benefits discussed herein. For example, processing circuitry 120 may execute instructions stored in device readable medium 130 or in memory within processing circuitry 120 to provide the functionality disclosed herein.

As illustrated, processing circuitry 120 includes one or more of RF transceiver circuitry 122, baseband processing circuitry 124, and application processing circuitry 126. In other embodiments, the processing circuitry may comprise different components and/or different combinations of components. In certain embodiments processing circuitry 120 of WD 110 may comprise a SOC. In some embodiments, RF transceiver circuitry 122, baseband processing circuitry 124, and application processing circuitry 126 may be on separate chips or sets of chips. In alternative embodiments, part or all of baseband processing circuitry 124 and application processing circuitry 126 may be combined into one chip or set of chips, and RF transceiver circuitry 122 may be on a separate chip or set of chips. In still alternative embodiments, part or all of RF transceiver circuitry 122 and baseband processing circuitry 124 may be on the same chip or set of chips, and application processing circuitry 126 may be on a separate chip or set of chips. In yet other alternative embodiments, part or all of RF transceiver circuitry 122, baseband processing circuitry 124, and application processing circuitry 126 may be combined in the same chip or set of chips. In some embodiments, RF transceiver circuitry 122 may be a part of interface 114. RF transceiver circuitry 122 may condition RF signals for processing circuitry 120.

In certain embodiments, some or all of the functionality described herein as being performed by a WD may be provided by processing circuitry 120 executing instructions stored on device readable medium 130, which in certain embodiments may be a computer-readable storage medium. In alternative embodiments, some or all of the functionality may be provided by processing circuitry 120 without executing instructions stored on a separate or discrete device readable storage medium, such as in a hard- wired manner. In any of those particular embodiments, whether executing instructions stored on a device readable storage medium or not, processing circuitry 120 can be configured to perform the described functionality. The benefits provided by such functionality are not limited to processing circuitry 120 alone or to other components of WD 110, but are enjoyed by WD 110 as a whole, and/or by end users and the wireless network generally.

Processing circuitry 120 may be configured to perform any determining, calculating, or similar operations (e.g., certain obtaining operations) described herein as being performed by a WD. These operations, as performed by processing circuitry 120, may include processing information obtained by processing circuitry 120 by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored by WD 110, and/or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination.

Device readable medium 130 may be operable to store a computer program, software, an application including one or more of logic, rules, code, tables, etc. and/or other instructions capable of being executed by processing circuitry 120. Device readable medium 130 may include computer memory (e.g., Random Access Memory (RAM) or Read Only Memory (ROM)), mass storage media (e.g., a hard disk), removable storage media (e.g., a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device readable and/or computer executable memory devices that store information, data, and/or instructions that may be used by processing circuitry 120. In some embodiments, processing circuitry 120 and device readable medium 130 may be considered to be integrated.

User interface equipment 132 may provide components that allow for a human user to interact with WD 110. Such interaction may be of many forms, such as visual, audial, tactile, etc. User interface equipment 132 may be operable to produce output to the user and to allow the user to provide input to WD 110. The type of interaction may vary depending on the type of user interface equipment 132 installed in WD 110. For example, if WD 110 is a smart phone, the interaction may be via a touch screen; if WD 110 is a smart meter, the interaction may be through a screen that provides usage (e.g., the number of gallons used) or a speaker that provides an audible alert (e.g., if smoke is detected). User interface equipment 132 may include input interfaces, devices and circuits, and output interfaces, devices and circuits. User interface equipment 132 is configured to allow input of information into WD 110, and is connected to processing circuitry 120 to allow processing circuitry 120 to process the input information. User interface equipment 132 may include, for example, a microphone, a proximity or other sensor, keys/buttons, a touch display, one or more cameras, a USB port, or other input circuitry. User interface equipment 132 is also configured to allow output of information from WD 110, and to allow processing circuitry 120 to output information from WD 110. User interface equipment 132 may include, for example, a speaker, a display, vibrating circuitry, a USB port, a headphone interface, or other output circuitry. Using one or more input and output interfaces, devices, and circuits, of user interface equipment 132, WD 110 may communicate with end users and/or the wireless network, and allow them to benefit from the functionality described herein.

Auxiliary equipment 134 is operable to provide more specific functionality which may not be generally performed by WDs. This may comprise specialized sensors for doing measurements for various purposes, interfaces for additional types of communication such as wired communications etc. The inclusion and type of components of auxiliary equipment 134 may vary depending on the embodiment and/or scenario.

Power source 136 may, in some embodiments, be in the form of a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic devices or power cells, may also be used. WD 110 may further comprise power circuitry 137 for delivering power from power source 136 to the various parts of WD 110 which need power from power source 136 to carry out any functionality described or indicated herein. Power circuitry 137 may in certain embodiments comprise power management circuitry. Power circuitry 137 may additionally or alternatively be operable to receive power from an external power source; in which case WD 110 may be connectable to the external power source (such as an electricity outlet) via input circuitry or an interface such as an electrical power cable. Power circuitry 137 may also in certain embodiments be operable to deliver power from an external power source to power source 136. This may be, for example, for the charging of power source 136. Power circuitry 137 may perform any formatting, converting, or other modification to the power from power source 136 to make the power suitable for the respective components of WD 110 to which power is supplied.

Figure 4 illustrates one embodiment of a UE in accordance with various aspects described herein. As used herein, a user equipment or UE may not necessarily have a user in the sense of a human user who owns and/or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, a UE may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter). UE 220 may be any UE identified by the 3^rd Generation Partnership Project (3GPP), including a NB-IoT UE, a machine type communication (MTC) UE, and/or an enhanced MTC (eMTC) UE. UE 200, as illustrated in Figure 4, is one example of a WD configured for communication in accordance with one or more communication standards promulgated by the 3^rd Generation Partnership Project (3GPP), such as 3GPP’s GSM, UMTS, LTE, and/or 5G standards. As mentioned previously, the term WD and UE may be used interchangeable. Accordingly, although Figure 4 is a UE, the components discussed herein are equally applicable to a WD, and vice-versa.

In Figure 4, UE 200 includes processing circuitry 201 that is operatively coupled to input/output interface 205, radio frequency (RF) interface 209, network connection interface 211, memory 215 including random access memory (RAM) 217, read-only memory (ROM) 219, and storage medium 221 or the like, communication subsystem 231, power source 233, and/or any other component, or any combination thereof. Storage medium 221 includes operating system 223, application program 225, and data 227. In other embodiments, storage medium 221 may include other similar types of information. Certain UEs may utilize all of the components shown in Figure 4, or only a subset of the components. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

In Figure 4, processing circuitry 201 may be configured to process computer instructions and data. Processing circuitry 201 may be configured to implement any sequential state machine operative to execute machine instructions stored as machine-readable computer programs in the memory, such as one or more hardware-implemented state machines (e.g., in discrete logic, FPGA, ASIC, etc.); programmable logic together with appropriate firmware; one or more stored program, general-purpose processors, such as a microprocessor or Digital Signal Processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 201 may include two central processing units (CPUs). Data may be information in a form suitable for use by a computer.

In the depicted embodiment, input/output interface 205 may be configured to provide a communication interface to an input device, output device, or input and output device. UE 200 may be configured to use an output device via input/output interface 205. An output device may use the same type of interface port as an input device. For example, a USB port may be used to provide input to and output from UE 200. The output device may be a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. UE 200 may be configured to use an input device via input/output interface 205 to allow a user to capture information into UE 200. The input device may include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, another like sensor, or any combination thereof. For example, the input device may be an accelerometer, a magnetometer, a digital camera, a microphone, and an optical sensor. In Figure 4, RF interface 209 may be configured to provide a communication interface to RF components such as a transmitter, a receiver, and an antenna. Network connection interface 211 may be configured to provide a communication interface to network 243a. Network 243a may encompass wired and/or wireless networks such as a local-area network (LAN), a wide-area network (WAN), a computer network, a wireless network, a telecommunications network, another like network or any combination thereof. For example, network 243a may comprise a Wi-Fi network. Network connection interface 211 may be configured to include a receiver and a transmitter interface used to communicate with one or more other devices over a communication network according to one or more communication protocols, such as Ethernet, TCP/IP, SONET, ATM, or the like. Network connection interface 211 may implement receiver and transmitter functionality appropriate to the communication network links (e.g., optical, electrical, and the like). The transmitter and receiver functions may share circuit components, software or firmware, or alternatively may be implemented separately.

RAM 217 may be configured to interface via bus 202 to processing circuitry 201 to provide storage or caching of data or computer instructions during the execution of software programs such as the operating system, application programs, and device drivers. ROM 219 may be configured to provide computer instructions or data to processing circuitry 201. For example, ROM 219 may be configured to store invariant low-level system code or data for basic system functions such as basic input and output (I/O), startup, or reception of keystrokes from a keyboard that are stored in a non-volatile memory. Storage medium 221 may be configured to include memory such as RAM, ROM, programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, floppy disks, hard disks, removable cartridges, or flash drives. In one example, storage medium 221 may be configured to include operating system 223, application program 225 such as a web browser application, a widget or gadget engine or another application, and data file 227. Storage medium 221 may store, for use by UE 200, any of a variety of various operating systems or combinations of operating systems.

Storage medium 221 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), floppy disk drive, flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro- DIMM SDRAM, smartcard memory such as a subscriber identity module or a removable user identity (SIM/RUIM) module, other memory, or any combination thereof. Storage medium 221 may allow UE 200 to access computer-executable instructions, application programs or the like, stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system may be tangibly embodied in storage medium 221, which may comprise a device readable medium.

In Figure 4, processing circuitry 201 may be configured to communicate with network 243b using communication subsystem 231. Network 243a and network 243b may be the same network or networks or different network or networks. Communication subsystem 231 may be configured to include one or more transceivers used to communicate with network 243b. For example, communication subsystem 231 may be configured to include one or more transceivers used to communicate with one or more remote transceivers of another device capable of wireless communication such as another WD, UE, or base station of a radio access network (RAN) according to one or more communication protocols, such as IEEE 802.2, CDMA, WCDMA, GSM, LTE, UTRAN, WiMax, or the like. Each transceiver may include transmitter 233 and/or receiver 235 to implement transmitter or receiver functionality, respectively, appropriate to the RAN links (e.g., frequency allocations and the like). Further, transmitter 233 and receiver 235 of each transceiver may share circuit components, software or firmware, or alternatively may be implemented separately.

In the illustrated embodiment, the communication functions of communication subsystem 231 may include data communication, voice communication, multimedia communication, short- range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof. For example, communication subsystem 231 may include cellular communication, Wi-Fi communication, Bluetooth communication, and GPS communication. Network 243b may encompass wired and/or wireless networks such as a local-area network (LAN), a wide-area network (WAN), a computer network, a wireless network, a telecommunications network, another like network or any combination thereof. For example, network 243b may be a cellular network, a Wi-Fi network, and/or a near field network. Power source 213 may be configured to provide alternating current (AC) or direct current (DC) power to components of UE 200.

The features, benefits and/or functions described herein may be implemented in one of the components of UE 200 or partitioned across multiple components of UE 200. Further, the features, benefits, and/or functions described herein may be implemented in any combination of hardware, software or firmware. In one example, communication subsystem 231 may be configured to include any of the components described herein. Further, processing circuitry 201 may be configured to communicate with any of such components over bus 202. In another example, any of such components may be represented by program instructions stored in memory that when executed by processing circuitry 201 perform the corresponding functions described herein. In another example, the functionality of any of such components may be partitioned between processing circuitry 201 and communication subsystem 231. In another example, the non- computationally intensive functions of any of such components may be implemented in software or firmware and the computationally intensive functions may be implemented in hardware.

Figure 5 is a schematic block diagram illustrating a virtualization environment 300 in which functions implemented by some embodiments may be virtualized. In the present context, virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices and networking resources. As used herein, virtualization can be applied to a node (e.g., a virtualized base station or a virtualized radio access node) or to a device (e.g., a UE, a wireless device or any other type of communication device) or components thereof and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components (e.g., via one or more applications, components, functions, virtual machines or containers executing on one or more physical processing nodes in one or more networks).

In some embodiments, some or all of the functions described herein may be implemented as virtual components executed by one or more virtual machines implemented in one or more virtual environments 300 hosted by one or more of hardware nodes 330. Further, in embodiments in which the virtual node is not a radio access node or does not require radio connectivity (e.g., a core network node), then the network node may be entirely virtualized.

The functions may be implemented by one or more applications 320 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) operative to implement some of the features, functions, and/or benefits of some of the embodiments disclosed herein. Applications 320 are run in virtualization environment 300 which provides hardware 330 comprising processing circuitry 360 and memory 390. Memory 390 contains instructions 395 executable by processing circuitry 360 whereby application 320 is operative to provide one or more of the features, benefits, and/or functions disclosed herein. Virtualization environment 300, comprises general-purpose or special-purpose network hardware devices 330 comprising a set of one or more processors or processing circuitry 360, which may be commercial off-the-shelf (COTS) processors, dedicated Application Specific Integrated Circuits (ASICs), or any other type of processing circuitry including digital or analog hardware components or special purpose processors. Each hardware device may comprise memory 390-1 which may be non-persistent memory for temporarily storing instructions 395 or software executed by processing circuitry 360. Each hardware device may comprise one or more network interface controllers (NICs) 370, also known as network interface cards, which include physical network interface 380. Each hardware device may also include non-transitory, persistent, machine-readable storage media 390-2 having stored therein software 395 and/or instructions executable by processing circuitry 360. Software 395 may include any type of software including software for instantiating one or more virtualization layers 350 (also referred to as hypervisors), software to execute virtual machines 340 as well as software allowing it to execute functions, features and/or benefits described in relation with some embodiments described herein.

Virtual machines 340, comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer 350 or hypervisor. Different embodiments of the instance of virtual appliance 320 may be implemented on one or more of virtual machines 340, and the implementations may be made in different ways.

During operation, processing circuitry 360 executes software 395 to instantiate the hypervisor or virtualization layer 350, which may sometimes be referred to as a virtual machine monitor (VMM). Virtualization layer 350 may present a virtual operating platform that appears like networking hardware to virtual machine 340.

As shown in Figure 5, hardware 330 may be a standalone network node with generic or specific components. Hardware 330 may comprise antenna 3225 and may implement some functions via virtualization. Alternatively, hardware 330 may be part of a larger cluster of hardware (e.g. such as in a data center or customer premise equipment (CPE)) where many hardware nodes work together and are managed via management and orchestration (MANO) 3100, which, among others, oversees lifecycle management of applications 320.

Virtualization of the hardware is in some contexts referred to as network function virtualization (NFV). NFV may be used to consolidate many network equipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers, and customer premise equipment. In the context of NFV, virtual machine 340 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine. Each of virtual machines 340, and that part of hardware 330 that executes that virtual machine, be it hardware dedicated to that virtual machine and/or hardware shared by that virtual machine with others of the virtual machines 340, forms a separate virtual network elements (VNE).

Still in the context of NFV, Virtual Network Function (VNF) is responsible for handling specific network functions that run in one or more virtual machines 340 on top of hardware networking infrastructure 330 and corresponds to application 320 in Figure 5.

In some embodiments, one or more radio units 3200 that each include one or more transmitters 3220 and one or more receivers 3210 may be coupled to one or more antennas 3225. Radio units 3200 may communicate directly with hardware nodes 330 via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node or a base station.

In some embodiments, some signalling can be effected with the use of control system 3230 which may alternatively be used for communication between the hardware nodes 330 and radio units 3200.

With reference to FIGURE 6, in accordance with an embodiment, a communication system includes telecommunication network 410, such as a 3GPP-type cellular network, which comprises access network 411 , such as a radio access network, and core network 414. Access network 411 comprises a plurality of base stations 4l2a, 4l2b, 4l2c, such as NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 413a, 413b, 413c. Each base station 412a, 412b, 412c is connectable to core network 414 over a wired or wireless connection 415. A first UE 491 located in coverage area 413c is configured to wirelessly connect to, or be paged by, the corresponding base station 412c. A second UE 492 in coverage area 413a is wirelessly connectable to the corresponding base station 412a. While a plurality of UEs 491, 492 are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole UE is in the coverage area or where a sole UE is connecting to the corresponding base station 412.

Telecommunication network 410 is itself connected to host computer 430, which may be embodied in the hardware and/or software of a standalone server, a cloud-implemented server, a distributed server or as processing resources in a server farm. Host computer 430 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. Connections 421 and 422 between telecommunication network 410 and host computer 430 may extend directly from core network 414 to host computer 430 or may go via an optional intermediate network 420. Intermediate network 420 may be one of, or a combination of more than one of, a public, private or hosted network; intermediate network 420, if any, may be a backbone network or the Internet; in particular, intermediate network 420 may comprise two or more sub-networks (not shown).

The communication system of Figure 6 as a whole enables connectivity between the connected UEs 491, 492 and host computer 430. The connectivity may be described as an over- the-top (OTT) connection 450. Host computer 430 and the connected UEs 491, 492 are configured to communicate data and/or signaling via OTT connection 450, using access network 411, core network 414, any intermediate network 420 and possible further infrastructure (not shown) as intermediaries. OTT connection 450 may be transparent in the sense that the participating communication devices through which OTT connection 450 passes are unaware of routing of uplink and downlink communications. For example, base station 412 may not or need not be informed about the past routing of an incoming downlink communication with data originating from host computer 430 to be forwarded (e.g., handed over) to a connected UE 491. Similarly, base station 412 need not be aware of the future routing of an outgoing uplink communication originating from the UE 491 towards the host computer 430.

Example implementations, in accordance with an embodiment, of the UE, base station and host computer discussed in the preceding paragraphs will now be described with reference to Figure 7. In communication system 500, host computer 510 comprises hardware 515 including communication interface 516 configured to set up and maintain a wired or wireless connection with an interface of a different communication device of communication system 500. Host computer 510 further comprises processing circuitry 518, which may have storage and/or processing capabilities. In particular, processing circuitry 518 may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. Host computer 510 further comprises software 511, which is stored in or accessible by host computer 510 and executable by processing circuitry 518. Software 511 includes host application 512. Host application 512 may be operable to provide a service to a remote user, such as UE 530 connecting via OTT connection 550 terminating at UE 530 and host computer 510. In providing the service to the remote user, host application 512 may provide user data which is transmitted using OTT connection 550. Communication system 500 further includes base station 520 provided in a telecommunication system and comprising hardware 525 enabling it to communicate with host computer 510 and with UE 530. Hardware 525 may include communication interface 526 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of communication system 500, as well as radio interface 527 for setting up and maintaining at least wireless connection 570 with UE 530 located in a coverage area (not shown in Figure 4) served by base station 520. Communication interface 526 may be configured to facilitate connection 560 to host computer 510. Connection 560 may be direct or it may pass through a core network (not shown in Figure 7) of the telecommunication system and/or through one or more intermediate networks outside the telecommunication system. In the embodiment shown, hardware 525 of base station 520 further includes processing circuitry 528, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. Base station 520 further has software 521 stored internally or accessible via an external connection.

Communication system 500 further includes UE 530 already referred to. Its hardware 535 may include radio interface 537 configured to set up and maintain wireless connection 570 with a base station serving a coverage area in which UE 530 is currently located. Hardware 535 of UE 530 further includes processing circuitry 538, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. UE 530 further comprises software 531, which is stored in or accessible by UE 530 and executable by processing circuitry 538. Software 531 includes client application 532. Client application 532 may be operable to provide a service to a human or non-human user via UE 530, with the support of host computer 510. In host computer 510, an executing host application 512 may communicate with the executing client application 532 via OTT connection 550 terminating at UE 530 and host computer 510. In providing the service to the user, client application 532 may receive request data from host application 512 and provide user data in response to the request data. OTT connection 550 may transfer both the request data and the user data. Client application 532 may interact with the user to generate the user data that it provides.

It is noted that host computer 510, base station 520 and UE 530 illustrated in Figure 7 may be similar or identical to host computer 430, one of base stations 4l2a, 4l2b, 4l2c and one of UEs 491, 492 of Figure 6, respectively. This is to say, the inner workings of these entities may be as shown in Figure 7 and independently, the surrounding network topology may be that of Figure 6. In Figure 7, OTT connection 550 has been drawn abstractly to illustrate the communication between host computer 510 and UE 530 via base station 520, without explicit reference to any intermediary devices and the precise routing of messages via these devices. Network infrastructure may determine the routing, which it may be configured to hide from UE 530 or from the service provider operating host computer 510, or both. While OTT connection 550 is active, the network infrastructure may further take decisions by which it dynamically changes the routing (e.g., on the basis of load balancing consideration or reconfiguration of the network).

Wireless connection 570 between UE 530 and base station 520 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to UE 530 using OTT connection 550, in which wireless connection 570 forms the last segment. More precisely, the teachings of these embodiments may improve the latency and thereby provide benefits such as reduced user waiting time and better responsiveness.

A measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring OTT connection 550 between host computer

510 and UE 530, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring OTT connection 550 may be implemented in software 511 and hardware 515 of host computer 510 or in software 531 and hardware 535 of UE 530, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which OTT connection 550 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software 511, 531 may compute or estimate the monitored quantities. The reconfiguring of OTT connection 550 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect base station 520, and it may be unknown or imperceptible to base station 520. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling facilitating host computer 5 l0’s measurements of throughput, propagation times, latency and the like. The measurements may be implemented in that software

511 and 531 causes messages to be transmitted, in particular empty or‘dummy’ messages, using OTT connection 550 while it monitors propagation times, errors etc.

Figure 8 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 6 and 7. For simplicity of the present disclosure, only drawing references to Figure 8 will be included in this section. In step 610, the host computer provides user data. In substep 611 (which may be optional) of step 610, the host computer provides the user data by executing a host application. In step 620, the host computer initiates a transmission carrying the user data to the UE. In step 630 (which may be optional), the base station transmits to the UE the user data which was carried in the transmission that the host computer initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 640 (which may also be optional), the UE executes a client application associated with the host application executed by the host computer.

Figure 9 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 6 and 7. For simplicity of the present disclosure, only drawing references to Figure 9 will be included in this section. In step 710 of the method, the host computer provides user data. In an optional substep (not shown) the host computer provides the user data by executing a host application. In step 720, the host computer initiates a transmission carrying the user data to the UE. The transmission may pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure. In step 730 (which may be optional), the UE receives the user data carried in the transmission.

Figure 10 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 6 and 7. For simplicity of the present disclosure, only drawing references to Figure 10 will be included in this section. In step 810 (which may be optional), the UE receives input data provided by the host computer. Additionally or alternatively, in step 820, the UE provides user data. In substep 821 (which may be optional) of step 820, the UE provides the user data by executing a client application. In substep 811 (which may be optional) of step 810, the UE executes a client application which provides the user data in reaction to the received input data provided by the host computer. In providing the user data, the executed client application may further consider user input received from the user. Regardless of the specific manner in which the user data was provided, the UE initiates, in substep 830 (which may be optional), transmission of the user data to the host computer. In step 840 of the method, the host computer receives the user data transmitted from the UE, in accordance with the teachings of the embodiments described throughout this disclosure. Figure 11 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 6 and 7. For simplicity of the present disclosure, only drawing references to Figure 11 will be included in this section. In step 910 (which may be optional), in accordance with the teachings of the embodiments described throughout this disclosure, the base station receives user data from the UE. In step 920 (which may be optional), the base station initiates transmission of the received user data to the host computer. In step 930 (which may be optional), the host computer receives the user data carried in the transmission initiated by the base station.

Any appropriate steps, methods, features, functions, or benefits disclosed herein may be performed through one or more functional units or modules of one or more virtual apparatuses. Each virtual apparatus may comprise a number of these functional units. These functional units may be implemented via processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include digital signal processors (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as read-only memory (ROM), random-access memory (RAM), cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and/or data communications protocols as well as instructions for carrying out one or more of the techniques described herein. In some implementations, the processing circuitry may be used to cause the respective functional unit to perform corresponding functions according one or more embodiments of the present disclosure.

Figure 12 depicts a method in accordance with particular embodiments, the method begins at step 1202 with determine a security token to provide in a request that is associated an RRC connection. A first procedure is used to determine the security token if the request is of a first type and a second procedure is used to determine the security token if the request is of a second type. Examples of procedures that may be used to generate different security tokens for different types of requests are provided in the Group A Embodiments below. In general, the first and second procedures may be based on the same integrity algorithm. In some embodiments, one or more inputs to the integrity algorithm may differ between the first and second procedures. In other embodiments, the same inputs may be used, but the first and second procedures may determine their respective security tokens based on different portions of the output. Thus, the first and second procedures yield different security tokens. At step 1204, the method continues with sending the request comprising the security token to a network node (such as the target gNB described above). At step 1206, the method continues with receiving a response from the network node that indicates that the security token has been successfully verified. In some embodiments, the indication that the security token has been successfully verified may be implicit (e.g., the network node allowing the wireless device to proceed as requested indicates that the security token has been successfully verified). At step 1208, the method completes the RRC connection based on the response.

The method of Figure 12 may be implemented in the signal flows of Figure 1 and Figure 2 above to discriminate between resume and re-establishment security tokens. As an example, suppose the first procedure is used to determine security token X if the request is of a first type (e.g., RRC Resume Request) and the second procedure is used to determine security token Y if the request is of a second type (e.g., RRC Re-establishment Request). In a first embodiment, the method sends an RRC Resume Request comprising security token X in step 1204, receives an RRC Resume in step 1206 (which indicates that security token X was successfully verified by the target gNB), and sends an RRC Resume Complete in step 1208. In a second embodiment, the method sends an RRC Re-establishment Request comprising security token Y in step 1204, receives an RRC Re-establishment in step 1206 (which indicates that security token Y was successfully verified by the target gNB), and sends an RRC Re-establishment Complete in step 1208. The preceding embodiments may be combined (e.g., the wireless device sends security token X with resume requests and security token Y with re-establishment requests).

Figure 13 depicts a method in accordance with particular embodiments. Figure 13 may be generally analogous to Figure 12 (e.g., Figure 12 describes functionality from the perspective of the wireless device, and Figure 13 describes analogous functionality from the perspective of a network node). At step 1312, the method receives a request associated with an RRC connection from a wireless device. The request comprises a security token. The request may be received directly from the wireless device or indirectly via another network node, depending on the embodiment. For example, in some embodiments, a source network node may receive the request via a retrieve UE context request from a target network node. At step 1314, the method determines whether the security token received in the request matches an expected security token based on a type of the request. Examples of procedures that may be used to obtain different expected security tokens for different types of requests are provided in the Group B Embodiments below. At step 1316, the method sends a response to the wireless device. The response depends on whether the security token received in the request matches the expected security token. The response may be sent directly to the wireless device or indirectly via another network node, depending on the embodiment. For example, in some embodiments, a source network node may send the response via a UE context response to a target network node.

The method of Figure 13 may be implemented in the signal flows of Figure 1 and Figure 2 above to discriminate between resume and re-establishment security tokens. As an example, suppose the expected security token X is calculated using a first procedure if the request is of a first type (e.g., RRC Resume Request) and the expected security token Y is calculated using a second procedure if the request is of a second type (e.g., RRC Re-establishment Request). In a first embodiment, the method receives an RRC Resume Request (or associated UE Context Request) comprising security token X in step 1312, determines that security token X matches expected security token X based on the type of request (resume request) in step 1314, and sends a response indicating that the security token X received in the request matches the expected security token X in step 1316. In some embodiments, the indication that the received security token matches the expected security token may be implicit (e.g., sending an RRC Resume or UE Context Response instead of a rejection). In a second embodiment, the method receives an RRC Re- establishment Request (or associated UE Context Request) comprising security token Y in step 1312, determines that security token Y matches expected security token Y based on the type of request (re-establishment request) in step 1314, and sends a response indicating that the security token Y received in the request matches the expected security token Y in step 1316. In some embodiments, the indication that the received security token matches the expected security token may be implicit (e.g., sending an RRC Re-establishment or UE Context Response instead of a rejection). The preceding embodiments may be combined (e.g., the network node matches expected security token X when receiving resume requests and matches expected security token Y when receiving re-establishment requests).

The above approaches may protect the wireless device from certain denial-of-service attacks. For example, suppose the gNB decides to suspend the wireless device in RRC connected state and therefore sends a suspend message. An attacker blocks the suspend message from reaching the wireless device and at the same time acknowledges the reception of the suspend message to the gNB, thereby fooling the gNB into believe the UE has entered RRC inactive state. The blocking of the suspend message will cause the wireless device to declare RLF and trigger RRC connection re-establishment, and the attacker will then intercept the security token Y in the RRC re-establishment request. The attacker can attempt to send an RRC resume request to the gNB with the intercepted security token Y, however, the gNB will not accept the attacker’s RRC resume request because the gNB requires security token X to resume the RRC connection. Figure 14 illustrates a schematic block diagram of an apparatus 1400 in a wireless network (for example, the wireless network shown in Figure 3). The apparatus may be implemented in a wireless device or network node (e.g., wireless device 110 or network node 160 shown in Figure 3). Apparatus 1400 is operable to carry out one or more of the example methods described with reference to Figures 12 and 13 and possibly any other processes or methods disclosed herein. It is also to be understood that the methods of Figures 12 and 13 are not necessarily carried out solely by apparatus 1400. At least some operations of the method can be performed by one or more other entities.

Virtual Apparatus 1400 may comprise processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include digital signal processors (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as read-only memory (ROM), random-access memory, cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and/or data communications protocols as well as instructions for carrying out one or more of the techniques described herein, in several embodiments. In some implementations, the processing circuitry may be used to cause resume unit 1402, re-establishment unit 1404, and security token unit 1406, and any other suitable units of apparatus 1400 to perform corresponding functions according one or more embodiments of the present disclosure.

As illustrated in Figure 14, apparatus 1400 includes resume unit 1402, re-establishment unit 1404, and security token unit 1406. Resume unit 1402 is configured to resume a suspended connection. In some embodiments, resume unit 1402 may send and/or receive one or more of the messages described with respect to FIGURE 1. Re-establishment unit 1404 is configured to re establish a failed connection. In some embodiments, re-establishment unit 1404 may send and/or receive one or more of the messages described with respect to FIGURE 2. Security token unit 1406 is configured to obtain security tokens to be transmitted or verified by resume unit 1402 and re-establishment unit 1404. In certain embodiments, security token unit 1406 calculates a first security token X to be transmitted or verified by resume unit 1402 and a second token Y to be transmitted or verified by re-establishment unit 1404.

The term unit may have conventional meaning in the field of electronics, electrical devices and/or electronic devices and may include, for example, electrical and/or electronic circuitry, devices, modules, processors, memories, logic solid state and/or discrete devices, computer programs or instructions for carrying out respective tasks, procedures, computations, outputs, and/or displaying functions, and so on, as such as those that are described herein.

SAMPLE EMBODIMENTS

General Embodiments

1. A method comprising calculating a security token, wherein at least a first part of the security token is used for a resume procedure and at least a second part of the security token is used for a re-establishment procedure.

2. The method of the previous embodiment, wherein inputs used to calculate the security token for the resume procedure are the same as inputs used to calculate the security token for the re-establishment procedure.

3. The method of the previous embodiment, wherein the values of the inputs used to

calculate the security token for the resume procedure are the same as the values of the inputs used to calculate the security token for the re-establishment procedure.

4. The method of any of the previous embodiments, wherein the first and second parts are different.

5. A method comprising calculating a security token, wherein inputs used to calculate the security token for a resume procedure are the same as inputs used to calculate the security token for a re-establishment procedure, and wherein, for at least one of the inputs, the value of the input used to calculate the security token for the resume procedure differs from the value of the input used to calculate the security token for the re-establishment procedure.

Group A Embodiments

1. A method performed by a wireless device, the method comprising:

- determining a security token to provide in a request that is associated with a radio resource control (RRC) connection, wherein a first procedure is used to determine the security token if the request is of a first type and a second procedure is used to determine the security token if the request is of a second type; and

- sending the request comprising the security token to a network node.

2. The method of the previous embodiment, wherein the first type of request is an RRC Resume Request and the second type of request is an RRC Re-establishment Request. The method of any of the previous embodiments, wherein the first procedure and the second procedure are different procedures based on the same integrity algorithm.

The method of the previous embodiment, wherein the integrity algorithm comprises a plurality of inputs.

The method of the previous embodiment, wherein the plurality of inputs comprise key, message, count, bearer, and direction parameters.

The method of the previous embodiment, wherein the key parameter is derived from a key associated with a network node in which the RRC connection was suspended or failed.

The method of any of embodiments 5-6, wherein the message parameter comprises an Abstract Syntax Notation One (ASN.l) encoded structure.

The method of embodiment 7, wherein the ASN.1 encoded structure contains a cell radio network temporary identifier (C-RNTI) of the wireless device in a source cell in which the RRC connection was suspended or failed, a physical cell identifier (PCI) of the source cell, and a cell identifier of a target cell of the network node that is being sent the request to resume or re-establish the RRC connection.

The method of any of embodiments 3-8, wherein the integrity algorithm generates an output based on a plurality of inputs, the first procedure and the second procedure provide the same input values to the integrity algorithm, and the first procedure determines the security token based on a different part of the output than the second procedure.

The method of the previous embodiment, wherein the first procedure determines the security token based on a number of most significant bits of the output and the second procedure determines the security token based on a number of least significant bits of the output, or vice versa.

The method of any of embodiments 3-7, wherein one or more input values provided by the first procedure differ from one or more input values provided by the second procedure.

The method of the previous embodiment, wherein the key parameter and the message parameter input values are the same for the first procedure and the second procedure, and at least one of the count parameter, bearer parameter, and direction parameter input values is different for the first procedure and the second procedure.

The method of any of the previous embodiments, wherein a third procedure is used to determine the security token if the request is of a third type.

14. The method of any of the previous embodiments, further comprising:

- receiving a response from the network node, the response indicating that the

security token has been successfully verified; and

- completing the RRC connection based on the response.

15. The method of any of the previous embodiments, further comprising:

- providing user data; and

- forwarding the user data to a host computer via the transmission to the base

station.

Group B Embodiments

16. A method performed by a base station, the method comprising:

- receiving a request associated with an RRC connection from a wireless device, the request comprising a security token;

- determining whether the security token received in the request matches an

expected security token based on a type of the request; and

- sending a response to the wireless device, the response depending on whether the security token received in the request matches the expected security token.

17. The method of the previous embodiment, wherein the response indicates that the security token matches the expected security token and the method further comprises:

- receiving a message from the wireless device that completes the RRC connection.

18. The method of embodiment 15, wherein the response comprises a rejection indicating that the security token received in the request does not match the expected security token.

19. The method of any of the previous embodiments, wherein the expected security token is based on a first procedure if the request is of a first type and a second procedure if the request is of a second type.

20. The method of the previous embodiment, wherein the first type of request is an RRC Resume Request and the second type of request is an RRC Re-establishment Request.

21. The method of the previous embodiment, wherein the first procedure and the second procedure are different procedures based on the same integrity algorithm.

22. The method of the previous embodiment, wherein the integrity algorithm comprises a plurality of inputs.

23. The method of the previous embodiment, wherein the plurality of inputs comprise key, message, count, bearer, and direction parameters.

The method of any of embodiments 23-24, wherein the message parameter comprises an Abstract Syntax Notation One (ASN.l) encoded structure.

The method of embodiment 26, wherein the ASN.l encoded structure contains a cell radio network temporary identifier (C-RNTI) of the wireless device in a source cell in which the RRC connection was suspended or failed, a physical cell identifier (PCI) of the source cell, and a cell identifier of a target cell of the network node that is being sent the request to resume or re-establish the RRC connection.

The method of any of embodiments 21-26, wherein the integrity algorithm generates an output based on a plurality of inputs, the first procedure and the second procedure provide the same input values to the integrity algorithm, and the first procedure determines the security token based on a different part of the output than the second procedure.

The method of any of embodiments 21-26, wherein one or more input values provided by the first procedure differ from one or more input values provided by the second procedure.

The method of any of the previous embodiments, wherein the expected security token is based on a third procedure if the request is of a third type.

The method of any of the previous embodiments, further comprising:

- obtaining user data; and

- forwarding the user data to a host computer or a wireless device. Group C Embodiments

33. A wireless device, the wireless device comprising:

- processing circuitry configured to perform any of the steps of any of the Group A embodiments; and

- power supply circuitry configured to supply power to the wireless device.

34. A base station, the base station comprising:

- processing circuitry configured to perform any of the steps of any of the Group B embodiments;

- power supply circuitry configured to supply power to the wireless device.

35. A user equipment (UE), the UE comprising:

- an antenna configured to send and receive wireless signals;

- radio front-end circuitry connected to the antenna and to processing circuitry, and configured to condition signals communicated between the antenna and the processing circuitry;

- the processing circuitry being configured to perform any of the steps of any of the Group A embodiments;

- an input interface connected to the processing circuitry and configured to allow input of information into the UE to be processed by the processing circuitry;

- an output interface connected to the processing circuitry and configured to output information from the UE that has been processed by the processing circuitry; and

- a battery connected to the processing circuitry and configured to supply power to the UE.

36. A computer program, the computer program comprising instructions which when

executed on a computer perform any of the steps of any of the Group A embodiments.

37. A computer program product comprising a computer program, the computer program comprising instructions which when executed on a computer perform any of the steps of any of the Group A embodiments.

38. A non-transitory computer-readable storage medium or carrier comprising a computer program, the computer program comprising instructions which when executed on a computer perform any of the steps of any of the Group A embodiments.

39. A computer program, the computer program comprising instructions which when

executed on a computer perform any of the steps of any of the Group B embodiments.

40. A computer program product comprising a computer program, the computer program comprising instructions which when executed on a computer perform any of the steps of any of the Group B embodiments.

A non-transitory computer-readable storage medium or carrier comprising a computer program, the computer program comprising instructions which when executed on a computer perform any of the steps of any of the Group B embodiments.

A communication system including a host computer comprising:

- processing circuitry configured to provide user data; and

- a communication interface configured to forward the user data to a cellular

network for transmission to a user equipment (UE),

- wherein the cellular network comprises a base station having a radio interface and processing circuitry, the base station’s processing circuitry configured to perform any of the steps of any of the Group B embodiments.

The communication system of the pervious embodiment further including the base station.

The communication system of the previous 2 embodiments, further including the UE, wherein the UE is configured to communicate with the base station.

The communication system of the previous 3 embodiments, wherein:

- the processing circuitry of the host computer is configured to execute a host application, thereby providing the user data; and

- the UE comprises processing circuitry configured to execute a client application associated with the host application.

A method implemented in a communication system including a host computer, a base station and a user equipment (UE), the method comprising:

- at the host computer, providing user data; and

- at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising the base station, wherein the base station performs any of the steps of any of the Group B embodiments.

The method of the previous embodiment, further comprising, at the base station, transmitting the user data.

The method of the previous 2 embodiments, wherein the user data is provided at the host computer by executing a host application, the method further comprising, at the UE, executing a client application associated with the host application.

A user equipment (UE) configured to communicate with a base station, the UE comprising a radio interface and processing circuitry configured to performs the of the previous 3 embodiments.

A communication system including a host computer comprising:

- processing circuitry configured to provide user data; and

- a communication interface configured to forward user data to a cellular network for transmission to a user equipment (UE),

- wherein the UE comprises a radio interface and processing circuitry, the UE’s components configured to perform any of the steps of any of the Group A embodiments.

The communication system of the previous embodiment, wherein the cellular network further includes a base station configured to communicate with the UE.

The communication system of the previous 2 embodiments, wherein:

- the UE’s processing circuitry is configured to execute a client application

associated with the host application.

- at the host computer, providing user data; and

- at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising the base station, wherein the UE performs any of the steps of any of the Group A embodiments.

The method of the previous embodiment, further comprising at the UE, receiving the user data from the base station.

A communication system including a host computer comprising:

- communication interface configured to receive user data originating from a

transmission from a user equipment (UE) to a base station,

- wherein the UE comprises a radio interface and processing circuitry, the UE’s processing circuitry configured to perform any of the steps of any of the Group A embodiments.

The communication system of the previous embodiment, further including the UE. The communication system of the previous 2 embodiments, further including the base station, wherein the base station comprises a radio interface configured to communicate with the UE and a communication interface configured to forward to the host computer the user data carried by a transmission from the UE to the base station.

The communication system of the previous 3 embodiments, wherein:

- the processing circuitry of the host computer is configured to execute a host application; and

- the UE’s processing circuitry is configured to execute a client application

associated with the host application, thereby providing the user data.

The communication system of the previous 4 embodiments, wherein:

- the processing circuitry of the host computer is configured to execute a host application, thereby providing request data; and

- the UE’s processing circuitry is configured to execute a client application

associated with the host application, thereby providing the user data in response to the request data.

- at the host computer, receiving user data transmitted to the base station from the UE, wherein the UE performs any of the steps of any of the Group A

embodiments.

The method of the previous embodiment, further comprising, at the UE, providing the user data to the base station.

The method of the previous 2 embodiments, further comprising:

- at the UE, executing a client application, thereby providing the user data to be transmitted; and

- at the host computer, executing a host application associated with the client application.

The method of the previous 3 embodiments, further comprising:

- at the UE, executing a client application; and

- at the UE, receiving input data to the client application, the input data being provided at the host computer by executing a host application associated with the client application,

- wherein the user data to be transmitted is provided by the client application in response to the input data.

A communication system including a host computer comprising a communication interface configured to receive user data originating from a transmission from a user equipment (UE) to a base station, wherein the base station comprises a radio interface and processing circuitry, the base station’s processing circuitry configured to perform any of the steps of any of the Group B embodiments.

65. The communication system of the previous embodiment further including the base

station.

66. The communication system of the previous 2 embodiments, further including the UE, wherein the UE is configured to communicate with the base station.

67. The communication system of the previous 3 embodiments, wherein:

- the processing circuitry of the host computer is configured to execute a host application;

- the UE is configured to execute a client application associated with the host

application, thereby providing the user data to be received by the host computer.

68. A method implemented in a communication system including a host computer, a base station and a user equipment (UE), the method comprising:

- at the host computer, receiving, from the base station, user data originating from a transmission which the base station has received from the UE, wherein the UE performs any of the steps of any of the Group A embodiments.

69. The method of the previous embodiment, further comprising at the base station,

receiving the user data from the UE.

70. The method of the previous 2 embodiments, further comprising at the base station,

initiating a transmission of the received user data to the host computer.

FIGURE 15 illustrates an example flowchart for a third example method 1500 for use in a wireless device, such as wireless device 1 lOb or 1 lOc or wireless device 200 described above in reference to FIGURES 3 and 4. Method 1500 may begin at step 1510 in which a security token is determined to provide in a request associated with an RRC connection. A first procedure is used to determine the security token if the request is an RRC Resume Request. A second procedure is used to determine the security token if the request is an RRC Re-establishment Request.

According to certain embodiments, the first procedure and the second procedure are different procedures using a same integrity algorithm. For example, as described above, the integrity algorithm, in some embodiments, generates an output based on a plurality of inputs comprising an integrity key value, a count value, a bearer identity value, a direction parameter value, and a message parameter. In some embodiments, the integrity key value is derived from a key associated with a source network node in which the RRC connection was suspended or failed. In some embodiments, the message parameter comprises an ASN.1 encoded structure containing a cell radio network temporary identifier C-R TI of the wireless device in a source cell in which the RRC connection was suspended or failed, a PCI of the source cell, and a cell identifier of a target cell of the target network node to which the request is sent. According to certain embodiments, the message parameter does not include a discriminating bit or sets of bits indicating a resume request or a re-establishment request.

The security tokens may be generated, via the first procedure or the second procedure based on this output of the integrity algorithm. For example, as described in the first set of embodiments above, the first procedure and the second procedure may use the same input values to the integrity algorithm to generate an output based on the input values. In particular, in certain embodiments, the first procedure determines the security token based on a first set of bits of the output different from a second set of bits of the output used by the second procedure to determine the security token. In some embodiments, the first procedure determines the security token based on one of a number of most significant bits of the output and the second procedure determines the security token based on a number of least significant bits of the output or vice-versa. In this manner, the two procedures result in differentiated security tokens for the resume and re- establishment requests without modifying the inputs to the integrity algorithm or including an explicit discriminator in the message parameter.

The security tokens may be generated in another manner, via the first procedure or the second procedure based on this output of the integrity algorithm. For example, as described in the second set of embodiments above, one or more input values provided by the first procedure for the integrity algorithm differ from one or more input values provided by the second procedure for the integrity algorithm. In some embodiments, the integrity key value and the message parameter input values are the same for the first procedure and the second procedure, and at least one of the count value, the bearer identity value, and the direction parameter value is different for the first procedure and the second procedure. The differences in those parameter values may be defined as part of a standard or as part of a configuration of the wireless device or network. Accordingly, the different security tokens can be generated by generating different outputs from the integrity algorithm via the different first and second procedures. In this manner, the selection process of the security token from the output of the algorithm can be the same (or unchanged) for both of the first and second procedures (because the same range of bits can be taken from different outputs resulting from the different inputs).

In some embodiments, a third procedure may be used to determine the security token if the request is not an RRC Resume Request or an RRC Re-establishment Request. For example, a different integrity algorithm may be used to generate the token, thereby resulting in a differentiated security token (e.g., due to the different algorithm even if the input values are the same). As another example, the same integrity algorithm may be used, but different inputs may be used to generate the output. As another example, different portions of the output may be used to determine the security token. As a particular example, there may be defined an input values that is used for the third procedure that is different from the input value(s) used by the first procedure or the second procedure. As another particular example, the third procedure may select a different set of bits from the output than selected by the first and second procedures. In this way, additional compartmentalized security tokens may be generated without requiring a dedicated differentiator in the message portion of the request.

Accordingly, a wireless device may generate a security token that is compartmentalized to a type of request, such that the security token may not be used with the other type of request. In particular, a security token may be generated for a resume request that would be different from the security token generated for a re-establishment request, even if the serving node and target node are the same.

At step 1520, the request comprising the security token is sent to a target network node in the wireless network. For example, the security token may be included in a resume request or a re-establishment request, e.g., as shown in the example signalling diagrams in FIGURES 1 and 2. The target network node may respond to the communication of the security token with one of a resume request or a re-establishment request. Accordingly, the differentiated security token may be used to initiate resuming or re-establishing a connection with the network.

In certain embodiments, method 1500 may include one or more additional or optional steps or substeps. For example, in certain embodiments, method 1500 includes the optional step 1530 in which a response from the target network node is received. The response may indicate that the security token has been successfully verified. At optional step 1540, the wireless device may complete the RRC connection based on the response. For example, the wireless device may receive a RRCResume or RRCReestablishment message from the target node and further signal with the target network node to complete the RRC connection and communicate on the RAN via the target node, e.g., sending and receive uplink and downlink data or control messages. In this manner, the wireless device may complete the process of resuming or re-establishing the connection with the wireless network in a secure manner.

FIGURE 16 illustrates an example flowchart for an example method 1600 for use in a network node, such as network node 160 as described above in reference to FIGURE 3. Method 1600 may begin at 1610, wherein a request associated with an RRC connection is received from a wireless device, e.g., wireless device l lOb or l lOc or wireless device 200 described above in reference to FIGURES 3 and 4. The request includes a security token. For example, the security token may be generated at the wireless device according to different procedures based on the type of RRC procedure is being requested in the request received by the network node. For example, the request may be a RRCResumeRequest or may be a RRCReestablishmentRequest. In certain embodiments, the security token differs based on the procedure used, e.g., which type of request is being generated, even if the target network node and the serving network node are the same, as described herein (see e.g., Figure 15).

At step 1620, the network node determines whether the security token received in the request matches an expected security token based on a type of the request. For example, if the network node receives a RRCResumeRequest, the network node may be configured to compare the received security token to the type of request and determine whether they match. As one particular example, the network node may run an algorithm or other procedure to generate an expected security token based on the type of request (in addition to other parameters such as the identification of the wireless device, target and serving nodes, etc.) and compare the expected security token with the received security token to determine if they match. In certain embodiments, the expected security token and the received security token may be determined to match if the security tokens match in certain locations/portions (e.g., if the received security token matches a certain number of most significant bits (or least significant bits) of the expected security token, or if the expected security token and received security token match above a threshold amount).

At step 1630, a response is sent to the wireless device. The response depends on whether the security token received in the request of step 1610 matches the expected security token of step 1620. For example, if the security token is received in a RRCResumeRequest but the security token does not match the RRCResume type (e.g., it matches a RRCReestablishmentRequest type), the response may include a rejection indicating that the security token received in the request does not match the expected security token. As another example, in certain embodiments, the network node confirms the security token matches the request type and proceeds with processing the request. As described above, this may include the resuming or re-establishment steps as shown in the signaling diagrams illustrated in FIGURES 1 or 2.

In certain embodiments, method 1600 may include one or more additional or optional steps or substeps. In certain embodiments, the response indicates that the security token matches the expected security token. At optional step 1640 a message is received from the wireless device that completes the RRC connection. For example, the network node may receive a RRCReestablishmentComplete message in response to a RRCReestablishment message sent to the wireless device, e.g., as sent in step 1630. As another example, the network node may receive a RRCResumeComplete message in response to a RRCResume message sent to the wireless device, e.g., as sent in step 1630. In this manner, the wireless device may communicate on the RAN via the network node, e.g., sending and receive uplink and downlink data or control messages, by completing the process of resuming or re-establishing connection with the wireless network in a secure manner.

Accordingly, a secure method for handling RRC requests may be provided at the network node. In particular, differentiated security tokens based on the type of RRC procedure may be generated and verified before using them to carry out a resuming or re-establishing of the connection between the wireless device and the network.

In some embodiments a computer program, computer program product or computer readable storage medium comprises instructions which when executed on a computer perform any of the embodiments disclosed herein. In further examples the instructions are carried on a signal or carrier and which are executable on a computer wherein when executed perform any of the embodiments disclosed herein.

Claims

1. A method (1500) for use in a wireless device in a wireless network, the method comprising:

determining (1510) a security token to provide in a request associated with a radio resource control (RRC) connection, wherein a first procedure is used to determine the security token if the request is an RRC Resume Request and a second procedure is used to determine the security token if the request is an RRC Re-establishment Request; and

sending (1520) the request comprising the security token to a target network node in the wireless network.

2. The method of Claim 1, wherein the first procedure and the second procedure are different procedures using a same integrity algorithm.

3. The method of Claim 2, wherein the integrity algorithm generates an output based on a plurality of inputs comprising an integrity key value, a count value, a bearer identity value, a direction parameter value, and a message parameter.

4. The method of Claim 3, wherein the integrity key value is derived from a key associated with a source network node in which the RRC connection was suspended or failed.

5. The method of any of Claims 3-4, wherein the message parameter comprises an Abstract Syntax Notation One (ASN.l) encoded structure containing a cell radio network temporary identifier (C-RNTI) of the wireless device in a source cell in which the RRC connection was suspended or failed, a physical cell identifier (PCI) of the source cell, and a cell identifier of a target cell of the target network node to which the request is sent.

6. The method of any of Claims 2-5, wherein the first procedure and the second procedure use the same input values to the integrity algorithm to generate an output based on the input values, and the first procedure determines the security token based on a first set of bits of the output different from a second set of bits of the output used by the second procedure to determine the security token.

7. The method of Claim 6, wherein: the first procedure determines the security token based on one of a number of most significant bits of the output and the second procedure determines the security token based on a number of least significant bits of the output; or

the first procedure determines the security token based on one of a number of least significant bits of the output and the second procedure determines the security token based on a number of most significant bits of the output.

8. The method of any of Claims 3-5, wherein one or more input values provided by the first procedure for the integrity algorithm differ from one or more input values provided by the second procedure for the integrity algorithm.

9. The method of Claim 8, wherein the integrity key value and the message parameter input values are the same for the first procedure and the second procedure, and at least one of the count value, the bearer identity value, and the direction parameter value is different for the first procedure and the second procedure.

10. The method of any of Claims 1-9, wherein a third procedure is used to determine the security token if the request is not an RRC Resume Request or an RRC Re-establishment Request.

11. The method of any of Claims 1-10, further comprising:

receiving (1530) a response from the target network node, the response indicating that the security token has been successfully verified; and

completing (1540) the RRC connection based on the response.

12. A method (1600) for use in a network node in a wireless network, the method comprising:

receiving (1610) a request associated with an RRC connection from a wireless device, the request comprising a security token;

determining (1620) whether the security token received in the request matches an expected security token based on a type of the request; and

sending (1630) a response to the wireless device, the response depending on whether the security token received in the request matches the expected security token.

13. The method of Claim 12, wherein the response indicates that the security token matches the expected security token and the method further comprises:

receiving (1640) a message from the wireless device that completes the RRC connection.

14. The method of Claim 12, wherein the response comprises a rejection indicating that the security token received in the request does not match the expected security token.

15. The method of any of Claims 12-14, wherein:

the expected security token is based on a first procedure if the request is of an RRC Resume Request and a second procedure if the request is an RRC Re-establishment Request; and

the first procedure and the second procedure are different procedures using a same integrity algorithm, wherein the integrity algorithm generates an output based on a plurality of inputs comprising an integrity key value, a count value, a bearer identity value, a direction parameter value, and a message parameter.

16. The method of Claim 15, wherein the integrity key value is derived from a key associated with a source network node in which the RRC connection was suspended or failed.

17. The method of any of Claims 15-16, wherein the first procedure and the second procedure use the same input values to the integrity algorithm to generate the output based on the input values, and the first procedure determines the security token based on a first set of bits of the output different from a second set of bits of the output used by the second procedure to determine the security token.

18. The method of any of Claims 15-16, wherein the integrity key value and the message parameter input values are the same for the first procedure and the second procedure, and at least one of the count value, the bearer identity value, and the direction parameter value is different for the first procedure and the second procedure.

19. A wireless device (110, l lOb, l lOc, 200) in a wireless network (106), the wireless device comprising:

a memory (130, 215) configured to store instructions; and processing circuitry (120, 201) configured to execute the instructions, whereby the wireless device is configured to:

determine a security token to provide in a request associated with a radio resource control (RRC) connection, wherein a first procedure is used to determine the security token if the request is an RRC Resume Request and a second procedure is used to determine the security token if the request is an RRC Re-establishment Request; and

send the request comprising the security token to a target network node (160, l60b) in the wireless network.

20. The wireless device of Claim 19, wherein the first procedure and the second procedure are different procedures using a same integrity algorithm.

21. The wireless device of Claim 20, wherein the integrity algorithm generates an output based on a plurality of input values comprising an integrity key value, a count value, a bearer identity value, a direction parameter value, and a message parameter.

22. The wireless device of Claim 21 , wherein the integrity key value is derived from a key associated with a source network node in which the RRC connection was suspended or failed.

23. The wireless device of any of Claims 21-22, wherein the message parameter comprises an Abstract Syntax Notation One (ASN. l) encoded structure containing a cell radio network temporary identifier (C-RNTI) of the wireless device in a source cell in which the RRC connection was suspended or failed, a physical cell identifier (PCI) of the source cell, and a cell identifier of a target cell of the target network node to which the request is sent.

24. The wireless device of any of Claims 20-23, wherein the first procedure and the second procedure use the same input values to the integrity algorithm to generate an output based on the input values, and the first procedure determines the security token based on a first set of bits of the output different from a second set of bits of the output used by the second procedure to determine the security token.

25. The wireless device of Claim 24, wherein: the first procedure determines the security token based on one of a number of most significant bits of the output and the second procedure determines the security token based on a number of least significant bits of the output; or

26. The wireless device of any of Claims 21-23, wherein one or more input values provided by the first procedure for the integrity algorithm differ from one or more input values provided by the second procedure for the integrity algorithm.

27. The wireless device of Claim 26, wherein the integrity key value and the message parameter input values are the same for the first procedure and the second procedure, and at least one of the count value, the bearer identity value, and the direction parameter value is different for the first procedure and the second procedure.

28. The wireless device of any of Claims 19-27, wherein a third procedure is used to determine the security token if the request is not an RRC Resume Request or an RRC Re- establishment Request.

29. The wireless device of any of Claims 19-28, wherein the wireless device is further configured to:

receive a response from the target network node, the response indicating that the security token has been successfully verified; and

complete the RRC connection based on the response.

30. A network node (160, l60b) in a wireless network (106), the network node comprising:

a memory (180) configured to store instructions; and

processing circuitry (170) configured to execute the instructions, whereby the network node is configured to:

receive a request associated with an RRC connection from a wireless device (110, 1 lOb, 1 lOc, 200), the request comprising a security token; determine whether the security token received in the request matches an expected security token based on a type of the request; and

send a response to the wireless device, the response depending on whether the security token received in the request matches the expected security token.

31. The network node of Claim 30, wherein the response indicates that the security token matches the expected security token and the network node is further configured to:

receive a message from the wireless device that completes the RRC connection.

32. The network node of Claim 30, wherein the response comprises a rejection indicating that the security token received in the request does not match the expected security token.

33. The network node of any of Claims 30-32, wherein:

34. The network node of Claim 33, wherein the integrity key value is derived from a key associated with a source network node in which the RRC connection was suspended or failed.

35. The network node of any of Claims 33-34, wherein the first procedure and the second procedure use the same input values to the integrity algorithm to generate the output based on the input values, and the first procedure determines the security token based on a first set of bits of the output different from a second set of bits of the output used by the second procedure to determine the security token.

36. The network node of any of Claims 33-34, wherein the integrity key value and the message parameter input values are the same for the first procedure and the second procedure, and at least one of the count value, the bearer identity value, and the direction parameter value is different for the first procedure and the second procedure.

37. A computer program product comprising a non-transitory computer readable medium (130) storing computer readable program code, the computer readable program code comprises: program code for determining a security token to provide in a request associated with a radio resource control (RRC) connection, wherein a first procedure is used to determine the security token if the request is an RRC Resume Request and a second procedure is used to determine the security token if the request is an RRC Re-establishment Request; and

program code for sending the request comprising the security token to a target network node in the wireless network.

38. The computer program product of Claim 37, wherein the computer readable program code further comprises computer readable program code to operate according to the method of any one of Claims 1 to 11.

39. A computer program product comprising a non-transitory computer readable medium (180) storing computer readable program code, the computer readable program code comprises: program code for receiving a request associated with an RRC connection from a wireless device, the request comprising a security token;

program code for determining whether the security token received in the request matches an expected security token based on a type of the request; and

program code for sending a response to the wireless device, the response depending on whether the security token received in the request matches the expected security token.

40. The computer program product of Claim 39, wherein the computer readable program code further comprises computer readable program code to operate according to the method of any one of claims 12-18.