WO2014084792A1

WO2014084792A1 - Methods and apparatuses for inter-ran reporting of connection status

Info

Publication number: WO2014084792A1
Application number: PCT/SE2013/051413
Authority: WO
Inventors: Mattias BERGSTRÖM; Yu Wang; Oumer Teyeb
Original assignee: Telefonaktiebolaget L M Ericsson (Publ)
Priority date: 2012-11-29
Filing date: 2013-11-29
Publication date: 2014-06-05

Abstract

With currently existing technologies the information regarding a terminal's communication in one wireless network is not readily available in another wireless network. This can be especially problematic if one wireless network is controlling the terminal's communication in the other wireless network. A method in a mobile terminal, 5 a mobile terminal, a method in a network node and a network node is disclosed. The mobile terminal transmits information to a first wireless network of the mobile terminal's connection status with respect to a second wireless network. The mobile terminal detects a trigger of a reporting event and then assembles a report in response to detecting the trigger of the reporting event. The report comprises information of a 10 connection status of the mobile terminal with respect to the second wireless network. Lastly the report is transmitted to the first wireless network

Description

Methods and apparatuses for Inter-RAN Reporting of Connection Status

Technical field

Embodiments of the present disclosure relates to a method in a mobile terminal and a mobile terminal for transmitting information to a first wireless network of the mobile terminal's connection status with respect to a second wireless network, and a method in a network node and a network node for receiving such information. Background

Using Wi-Fi/Wireless Local Area Network (WLAN), the two terms are used interchangeably throughout this application, to offload traffic from the mobile networks is becoming more and more interesting from both the operator's and end user's points of view. Some of the reasons for this tendency are:

• Additional frequency: by using Wi-Fi, operators can access an additional 85MHz of radio bandwidth in the 2.4GHz band and another (close to) 500MHz in the 5GHz band. · Cost: From the operator's point of view, Wi-Fi uses unlicensed frequency that is free of charge. On top of that, the cost of Wi-Fi Access Points (APs), both from capital expense (CAPEX) and operational expense (OPEX) aspects, is considerably lower than that of a 3GPP base station (BS/eNB). Operators can also take advantage of already deployed APs that are already deployed in hotspots such as train stations, airports, stadiums, shopping malls, etc. Most end users are also currently used to having Wi-Fi for free at home (as home broadband subscriptions are usually flat rate) and public places.

• Terminal support: Many User Equipments (UEs), including virtually all smartphones, and other portable devices currently available in the market support Wi-Fi. In the Wi-Fi world, the term Station (STA) is used instead of UE, and as such the terms UE, STA and terminal are used interchangeably in this document. • High data rate: Under low interference conditions and assuming the user is close to the Wi-Fi AP, Wi-Fi can provide peak data rates that outshine that of current mobile networks (for example, theoretically up to 600Mbps for IEEE 802.1 1 η deployments with Multiple Input Multiple Output (MIMO)).

A very simplified Wi-Fi architecture is discussed below where the UE/STA is connected to the Wi-Fi Access Point (AP), which can directly be connected to the Internet. In the control plane, an Access point Controller (AC) handles the management of the AP. One AC usually handles the management of several APs. Security/authentication of users is handled via an Authentication, Authorization and Accounting (AAA) entity. Remote Administration Dial In User Service (RADIUS) is the most widely used network protocol for providing a centralized AAA management (RFC 2865).

Most current WiFi deployments are totally separate from mobile networks, and are to be seen as non-integrated. From the terminal perspective, most mobile operating systems (OS) for UEs such as Android and iOS, support a simple WiFi offloading mechanism, where the UEs immediately switch all their PS (Packet Switched) bearers to a WiFi network upon a detection of such a network with a certain signal level. The decision to offload to a WiFi or not is referred henceforth as access selection strategy and the aforementioned strategy of selecting WiFi whenever such a network is detected is known as "WiFi-if- coverage".

There are several drawbacks of the WiFi-if-coverage strategy as illustrated in Figure 1 : · Though the user/UE can save previous passcodes for already accessed WiFi Access Points (APs), hotspot login for previously un-accessed APs usually requires user intervention, either by entering the passcode in WiFi connection manager or using a web interface. • Interruptions of ongoing services can occur due to the change of IP address when the UE switches to the WiFi network. For example, a user who started a VoIP call while connected to a mobile network is likely to experience call drop when arriving home and the UE switching to the WiFi network automatically. Though some applications are smart enough to handle this and to survive the IP address change (e.g., Spotify), the majority of current applications cannot. It also places a lot of burden on application developers if they have to ensure service continuity.

• No consideration of expected radio performance is made, and this can lead to a UE being handed over from a high data rate mobile network link to a low data rate via the WiFi link. Even though the UE's OS or some high level software is smart enough to make the offload decisions only when the signal level on the WiFi is considerably better than the mobile network link, there can still be limitations on the backhaul that the WiFi AP is using that may end up being the bottle neck.

• No consideration of the load conditions in the mobile network and WiFi are made. As a result, the UE might still be offloaded to a WiFi AP that is serving several UEs while the mobile network (e.g., LTE) that it was previously connected to is rather unloaded. · No consideration of the UE's mobility is made. Due to this, a fast moving UE can end up being offloaded to a WiFi AP for a short duration, just to be handed over back to the mobile network. This is specially a problem in scenarios like cafes with open WiFi, where a user walking by or even driving by the cafe might be affected by this. Such ping pong between the WiFi and mobile network can cause service interruptions as well as generate considerable unnecessary signaling (e.g. towards authentication servers)

In order to combat these problems, WiFi/3GPP integration mechanisms have been proposed. The Access Network Discovery and Selection Function (ANDSF) is an entity defined by the Third Generation partnership project (3GPP) for providing access discovery information as well as mobility and routing policies to the UE. ANDFS is a new entity added to the 3GPP architecture in Release 8 of 3GPP TS 23.402 (See "Architecture Enhancements for non- 3GPP Accesses," 3GPP TS 23.402, v. 1 1 .4.0 (Sept. 2012), available at www.3gpp.org). A ANDSF server is only connected to the UE, and its main goal is to provide the UE with access network information in a resource efficient and secure manner. The communication between the UE and the ANDSF server is defined as an IP-based S14-interface. By supplying information about both available 3GPP and non-3GPP access networks to the UE, the ANDSF enables an energy-efficient mechanism of network discovery, where the UE can avoid continuous and energy-consuming background scanning. Furthermore, the ANDSF provides the mobile operators with a tool for the implementation of flexible and efficient UE steering of access mechanisms, where policy control can guide UEs to select one particular radio access network (RAN) over another. Note that this may be an overstatement if ANDSF is implemented as an "app", since it then relies on operating system (OS) support and prioritization of ANDSF in relation to other "apps". This condition may be only partly fulfilled, which thus makes the control of the UE via the ANDSF somewhat unreliable.

The ANDSF supplies three types of information - discovery information, inter-system mobility policies (ISMP) and inter-system routing policies (ISRP). All these are summarized and implemented via ANDSF managed objects (MO), which are communicated to the UEs via an over-the-top (OTT) signaling channel, as Simple Object Access Protocol - Extensible Markup Language (SOAP-XML) messages.

One prior art solution is to have a WLAN network indicating its network conditions to the cellular network using a mobile terminal as a relay, see "Load Balancing for Cellular/WLAN integrated Networks" by Wei Song et al.

With the proliferation of devices that have both Wi-Fi and 3GPP mobile broadband support, offloading traffic to the Wi-Fi network is becoming very interesting, both from the user's and the operator's perspectives. The main difference between traffic steering in the Wi-Fi case as compared to steering between 3GPP networks (or 3GPP-"friendly" networks such as CDMA2000) is that it is the terminal that decides when it shall select a Wi-Fi Access Point (AP), while in the latter case it is the network that is in charge of the network access decisions. Due to technical and historical reasons, the Wi-Fi deployment scenario is in many cases fundamentally different than the cellular deployment. For this reason, special considerations have to be made when integrating Wi-Fi to 3GPP networks. Summary

One issue with currently existing technologies is that information regarding a terminal's communication in one wireless network is not readily available in another wireless network. This can be especially problematic if one wireless network is controlling the terminal's communication in the other wireless network.

Several embodiments of the disclosure herein, therefore, include methods in a mobile terminal 500 and a wireless network for communicating to a first wireless network information of the terminal's connection, or lack thereof, to a second wireless network. This is realized by the terminal 500 signaling to the first network information regarding the connection status of the terminal 500 with respect to the second network. Methods are presented where the terminal 500 reports information about the status of the radio used for the other network as well as information about the terminals current communication situation on the second network. Different triggers for the terminal 500 to report are presented, one such trigger being a request from the network. Some example applications for when the network requests the report are also presented. Several methods disclosed herein may be implemented by a mobile terminal 500 capable of operating in at least a first wireless network, e.g a first RAN and possibly a second wireless network e.g. a second RAN, such as via both a wide-area network technology and a wireless local-area network technology. One such example method begins with receiving information that specifies all or part of the report contents, from the first wireless network, e.g., from an eNodeB. This operation may not occur in all embodiments or in all circumstances. For example, all or part of the contents may be determined by the mobile terminal 500, based on current conditions, or may be specified by an industry standard. The method continues with the detecting of a trigger of a reporting event e.g. reporting trigger event. This may be a local event, in some embodiments and/or circumstances, such as a locally generated service request. In some cases, the trigger event may be a connection or disconnection to the second wireless network e.g., a Wi-Fi access point. In still other embodiments and/or circumstances, the trigger event may be the receiving of an explicit report request from the first wireless network. Note that in some cases a report request from the first wireless network may specify all or part of the contents of the requested report.

In response to the detected trigger event, the mobile terminal 500 assembles the report, including information of the connection status of the mobile terminal 500 with respect to the second network. This may be achieved by any combination of the parameters suggested above. The mobile terminal 500 then transmits the report to the first wireless network e.g., to an LTE eNodeB. In some cases, depending on the contents of the report and the conditions at the first wireless network, the mobile terminal 500 may subsequently receive an order to steer its traffic to the second wireless network, for example, or may receive scheduling grants that have been prioritized or de-prioritized in response to the report.

Other methods disclosed herein complement the above methods and may be implemented by a network node in a first wireless network, where the network node is generally configured to control one or more mobile terminals capable of operating in (at least) the first wireless network and a second wireless network, such as in an LTE network and a Wi-Fi network. The method may be carried out in a base station, such as an eNodeB in an LTE network, for example. However, it may also be carried out by another node in a network, such as a scheduling node or controller node that is separate from a radio base station, in which case communication with the mobile terminal 500 is typically carried out via a radio base station.

One such method begins with sending information that specifies all or part of the desired report contents to a mobile terminal. This may not occur in all embodiments or in all circumstances. As discussed above, for example, all or part of the contents may be determined by the mobile terminal, based on current conditions, or may be specified by an industry standard.

In some embodiments, the network node sends a report request to one or more mobile terminals. (Note that information specifying all or part of the report contents may be combined with a report request, in some embodiments.) Again, this may not occur in all embodiments or in all circumstances. In some cases, for example, reports might only be sent by mobile terminals in response to other trigger events detected by the mobile terminals. In some embodiments, the mobile terminals may send reports in response to both explicit report requests sent by the network and other trigger events.

In any case, the network node receives a report from each of one or more mobile terminals, the report wherein the report comprises information of a connection status of the mobile terminal 500 with respect to a second wireless network. For each mobile terminal 500 the report characterize a connection status for the mobile terminal 500 with respect to a second wireless network, such as a Wi-Fi network. The report may contain any or all of the parameters discussed earlier. The network node evaluates the report(s), e.g., in conjunction with information about conditions at the first wireless network, such as network or base station loading conditions. Responsive to this evaluation and depending on the information conveyed by the reports, the network node may proceed by steering traffic for one or more mobile terminals to or from the second wireless network, or by prioritizing scheduling for one or more mobile terminals, or both.

Other embodiments include terminals adapted to carry out one or more of the terminal- based methods summarized above, as well as network node apparatus adapted to carry out one or more of the network-based methods summarized above. A mobile terminal 500 for communicating information to a first wireless network of the mobile terminal's connection status to a second wireless network is thus disclosed. The mobile terminal 500 comprises a processing circuit and a transmitter. The processing circuit is configured to detect a trigger of a reporting event and further configured to assemble a report in response to a detected trigger of the reporting event, wherein the report comprises information of a connection status of the mobile terminal 500 with respect to the second wireless network. The transmitter is configured to transmit the report to the first wireless network.

A network node configured to control one or more mobile terminals capable of operating in a first wireless network and a second wireless network the network node is also disclosed. The network node comprises a processing circuit and a transceiver. The transceiver is configured to receive a report from the one or more mobile terminals, wherein the report comprises information of a connection status of the mobile terminal 500 with respect to a second wireless network. The processing circuit is configured to evaluate the one or more reports and further configured to steer traffic for the one or more mobile terminals to or from the second wireless network based on the evaluated one or more reports or to prioritize scheduling for the one or more mobile terminals based on the evaluated one or more reports.

The disclosed techniques and apparatus make it possible for a first wireless network to have information regarding a terminal's connection status with respect to a second wireless network, regardless of the level of integration between the first and second wireless network. This information may be considered by the first wireless network, for example, when performing scheduling, deciding whether a terminal's connection, to the first or the second wireless network, shall be maintained or terminated, whether a terminal 500 shall communicate over the first or second wireless network, etc. An additional advantage is that the disclosed techniques and apparatus can be implemented without changing or modifying already existing and deployed AP.

An additional advantage is that the first wireless network knows exactly which mobile terminal 500 that is for example causing a load in the second wireless network or which mobile terminal 500 that can be handed over to the second wireless network. This allows a more precise utilization of radio resources and load balancing.

Brief description of the drawings

Examples of embodiments herein are described in more detail with reference to attached drawings in which:

Fig .1 schematically illustrates different scenarios to consider when having multiple wireless networks.

Fig. 2 is a process flow diagram illustrating an example of method, according to some embodiments of the disclosure. Fig. 3 is a process flow diagram illustrating an example method implemented by a mobile terminal.

Fig. 4 is a process flow diagram illustrating a complementary example method implemented by a network node

Fig. 5 illustrates an example terminal according to several embodiments of the present disclosure.

Fig. 6 illustrates an example network node according to several embodiments of the present disclosure.

Fig. 7 schematically illustrates an example terminal and an example network node in a system.

Detailed description

In the discussion that follows, specific details of particular embodiments of the present disclosure are set forth for purposes of explanation and not limitation. It will be appreciated by those skilled in the art that other embodiments may be employed apart from these specific details. Furthermore, in some instances detailed descriptions of well-known methods, nodes, interfaces, circuits, and devices are omitted so as not obscure the description with unnecessary detail. Those skilled in the art will appreciate that the functions described may be implemented in one or in several nodes. Some or all of the functions described may be implemented using hardware circuitry, such as analog and/or discrete logic gates interconnected to perform a specialized function, ASICs, PLAs, etc. Likewise, some or all of the functions may be implemented using software programs and data in conjunction with one or more digital microprocessors or general purpose computers. Where nodes that communicate using the air interface are described, it will be appreciated that those nodes also have suitable radio communications circuitry. Moreover, the technology can additionally be considered to be embodied entirely within any form of computer-readable memory, including non-transitory embodiments such as solid-state memory, magnetic disk, or optical disk containing an appropriate set of computer instructions that would cause a processor to carry out the techniques described herein.

Hardware implementations of the present disclosure may include or encompass, without limitation, digital signal processor (DSP) hardware, a reduced instruction set processor, hardware (e.g., digital or analog) circuitry including but not limited to application specific integrated circuit(s) (ASIC) and/or field programmable gate array(s) (FPGA(s)), and (where appropriate) state machines capable of performing such functions.

In terms of computer implementation, a computer is generally understood to comprise one or more processors or one or more controllers, and the terms computer, processor, and controller may be employed interchangeably. When provided by a computer, processor, or controller, the functions may be provided by a single dedicated computer or processor or controller, by a single shared computer or processor or controller, or by a plurality of individual computers or processors or controllers, some of which may be shared or distributed. Moreover, the term "processor" or "controller" also refers to other hardware capable of performing such functions and/or executing software, such as the example hardware recited above.

Throughout the disclosure, the term RAN, Radio Access Network is used interchangeably with the term wireless network. The same also applies for the terms UE, STA, mobile terminal and terminal.

An exemplary system comprising a first wireless network and a second wireless network is disclosed in figure 7. When referring to a first wireless system a reference is made to at least a base station or similar network node representing a first RAN 600, 601 or radio access network. Also, when referring to a second wireless system a reference is made to at least a base station or similar network node representing a second RAN or radio access network. Also disclosed in figure 7 are a number of mobile terminals 500, 501 in communication with at least one of the wireless networks 600, 601 . It is also possible that the first and second wireless networks are connected to an IP network 603.

One issue with currently existing technologies is that information regarding a terminal's connection in one RAN is not readily available in another RAN. Embodiments of the present disclosure address this problem by enabling the terminal 500 to report to a first RAN its connection status with respect to a second RAN. This is beneficial as the two RANs may not be integrated and hence information about terminals connection status with respect to the second RAN is not available to the first RAN. Even if the two RAN are integrated, e.g. at core network level, such information may not be available to the first RAN.

In the embodiments described in detail below, the first RAN is a cellular network such as an LTE RAN, while the second RAN is a Wi-Fi. However, this is just an example and the embodiments may be applied also to other scenarios where the RANs are of other RATs. It may also be so that the first and the second RAN use the same RAT (e.g., the same RAT operated at different frequencies). Since Wi-Fi is typically used as an overlay layer to boost capacity of the LTE RAN, it is expected that the decision whether or not a terminal 500 shall communicate using Wi-Fi will be made in the LTE network. For example, the LTE network can order a terminal 500 to connect to a Wi-Fi access point and to steer the data traffic for at least some services over the Wi-Fi link. The LTE network may also order the terminal 500 to disconnect from Wi-Fi if the performance over the Wi-Fi is not as expected.

However, the LTE network may not be aware of the status of the terminal's connection status over Wi-Fi, e.g., it may not be aware if the Wi-Fi radio is turned on or off, if the terminal 500 supports simultaneous connections to both LTE and Wi-Fi, i.e. dual connectivity, if the terminal's data traffic from the service which was steered to Wi-Fi has ended, if the Wi-Fi throughput is/was high or low, etc. Thus the LTE network may not have all the necessary information to decide if the terminal's connection to the Wi-Fi access point shall be maintained or if it can be terminated. An example scenario where the LTE network may order UEs to connect to Wi-Fi is when the LTE load is high, which will reduce the quality of experience of all connected terminals. If two terminals are connected to an overloaded LTE base station and a terminal A has a connection to a Wi-Fi access point, while a terminal B has no Wi-Fi connection, if the network knows that terminal A has a backup connection then it may therefore order terminal A to steer all or some traffic from LTE to Wi-Fi, which would reduce the load of the LTE base station. Alternatively the network may prioritize terminal B higher than terminal A when scheduling, since terminal A also has a Wi-Fi connection. If both terminals are connected to Wi-Fi access points and support dual connectivity, the network may consider the throughput experienced by the two terminals when scheduling and prioritizing the terminal that has a worse Wi-Fi link.

Another example scenario in which the techniques described here can be used is when power saving is important. For example, if the network knows that the terminals connected to a certain LTE base station can receive sufficiently good service from Wi-Fi, the network may order the terminals to steer their traffic to Wi-Fi and terminate their connection to the LTE base station. The LTE base station may then be able to enter a power saving state. Figure 2 is a process flow diagram illustrating an example of a method, according to some embodiments of the disclosure.

As shown at block 210, the illustrated process begins with a mobile terminal 500 for example a mobile terminal A, which is an end user terminal capable of accessing service using two different RATs, that is being able to connect to both an LTE network and a Wi-Fi network. Block 210 indicates that the LTE network load (at least at the relevant base station - eNodeB, in 3GPP terms) is initially low. As noted above, the specific RATs shown here are only possible examples; other combinations of RATs and RANs are possible. As shown at block 220, the loading on the LTE network increases, as more terminals connect. In response to detecting this increase in network load, the network (e.g., the eNodeB) requests Terminal A to provide a Wi-Fi status report, as shown at block 230. This report generally characterizes terminal A's connection or lack thereof to the second RAN (where the LTE network is the first RAN), in this case the Wi-Fi access point. Details of several example contents of this status report are described below.

As shown at block 240, terminal A determines which information to include in the report. Terminal A transmits the report to the network (e.g., to the LTE eNodeB), as shown at block 250.

As shown at block 260, the network (e.g., the eNodeB) evaluates the report, perhaps along with similar reports from other terminals served by the network. Depending on the contents of the report, the network may determine that terminal A's Wi-Fi link is good enough for communication, and thus orders terminal A to steer some or all of its traffic to Wi-Fi, as shown at block 270. As indicated above, the network may take other actions in response to the report, instead of or in addition to ordering terminal A to steer traffic to the second RAN. For instance, the network (e.g., the eNodeB) may deprioritize terminal A in its scheduling decisions, based on a determination that terminal A has access to a reliable Wi-Fi link.

Some example information or information elements which could be included in the report are described in the below sections. Radio status

The connection status may indicate a radio status of the mobile terminal 500 as exemplified below.

A first radio status parameter is the capability of the terminal 500 of communicating with the second wireless network. For example, one important parameter to report is the terminal's Wi-Fi capability. It may be so that not all terminals are able to perform Wi-Fi communication. Whether a terminal 500 is capable of Wi-Fi communication may be scenario dependent and may therefore change over time. For example, a terminal 500 which has Wi-Fi support may not be able to use it if the Bluetooth is also active, since there might be some maximum total power transmission limit from all RATs per terminal.

The terminals Wi-Fi capability maybe communicated to the network in two general ways:

1 Explicit signaling from the terminals to the network (e.g. by enhancing legacy UE capability information exchange).

2 Implicitly from the IMEI (International Mobile Equipment Identity). The Type Allocation Code (TAC), which is the initial eight digit portion of the 15 digit IMEI code, identifies a particular model (and often revision) of a wireless device. The network could have a mapping of the TAC to the device capability regarding other RATs.

A second radio status parameter is whether a radio in the mobile terminal 500 for communicating with the second wireless network is on or off. This parameter indicates whether the terminal's Wi-Fi radio is on or off. This parameter is useful, in some embodiments of the disclosure, because for many terminals the Wi-Fi radio can be turned on and off by the user, by an application, etc. Therefore it may not be sufficient for the network to get the information about the terminal's Wi-Fi capability alone, as the network would not know whether the terminal's Wi-Fi radio is actually turned on or off. A third radio status parameter is whether the mobile terminal 500 is associated or connected to the second wireless network. Whether or not the terminal 500 is currently associated with/connected to a Wi-Fi access point is also an important parameter to consider, and that may be included in the report, in some embodiments. In case the terminal 500 is autonomously performing the decision to connect to Wi-Fi or not, the LTE network may not be aware that the terminal 500 has connected to a Wi-Fi. According to one alternative of this embodiment, if the terminal 500 is connected to a Wi-Fi access point, the terminal 500 may also include an identifier of the Wi-Fi access point, for example the SSID. This indicator allows the network to prioritize different Wi-Fi access points differently. For example, the network may prioritize the users' home Wi-Fi access point higher than other, e.g. public Wi-Fi access points.

A fourth radio status parameter is the version of the communication protocol used in the mobile terminal 500 for communicating with the second wireless network, and for example which versions of Wi-Fi are supported by the terminal 500 as well as the Wi-Fi AP the terminal 500 is connecting. Different versions of Wi-Fi, e.g., the b,g,a,n and ac version of 802.1 1 , provides different peak data rates and capacity. Such information could be useful for the LTE network when taking decisions of traffic steering. As discussed above, the terminals TAC could be used to implicitly find out the version of Wi-Fi to be supported. Communication status

The connection status may indicate a communication status of the mobile terminal 500 as exemplified below.

A first communication status parameter is the throughput with respect to the second wireless network. A second communication status parameter is the bit rate with respect to the second wireless network. The throughput and/or bitrate the terminal 500 experiences on the Wi-Fi link is also a parameter that could be useful to consider, and that may be included in the report in some embodiments. This may be an average throughput/bitrate the terminal 500 has experienced during the past period of time T, for example. This information may be beneficial for the network to know, for instance, when determining scheduling priority between different terminals in the LTE network. A terminal 500 that experiences lower throughput in Wi-Fi may be given higher priority by eNodeB when scheduled in LTE, compared to a terminal 500 that experiences higher throughput in Wi-Fi.

A third communication status parameter is the latency with respect to the second wireless network. Another possible indicator indicates the latency the terminal 500 experiences on the Wi-Fi link. This may be an average delay the terminal 500 has experienced during the past period of time T, for example. This information may be useful for the LTE network to determine whether a terminal 500 should carry a service in LTE or Wi-Fi. For example if the Wi-Fi latency is sufficiently low, the LTE network may order the terminal 500 to steer the traffic from that service to Wi-Fi.

A fourth communication status parameter is the amount of data transmitted or received with respect to the second wireless network. In some embodiments, the terminal 500 indicates to the network the amount of data communicated by the terminal 500 over the Wi-Fi access point during a time period T. Alternatively the terminal 500 may indicate whether or not the amount of data communicated exceeds a certain threshold. It is beneficial for the LTE network to know this, for example, as it can be used when determining if the network shall order the terminal 500 to terminate its Wi-Fi connection or not. If a terminal 500 indicates that it has not used the Wi-Fi connection for data communication for some time, the network may judge that the connection to the Wi-Fi access point can be terminated, so as to save terminal battery power. If the terminal 500 indicates that a lot of data has been communicated through the Wi-Fi access point the network may order the terminal 500 not to terminate the connection to the Wi-Fi access point.

The time T discussed in relation to the first to fourth communication status parameter may be indicated by the network, for example, prior to the report transmission. Another example is that the time T may be specified in a specification so as to avoid the signaling of time T.

A fifth communication status parameter is the uplink-downlink traffic distribution with respect to the second wireless network. The status for uplink and for downlink can be communicated separately in the report, in some embodiments. The uplink and downlink traffic, both for a given terminal as well as the overall network, is often not symmetrical, and hence it may be necessary for the network (e.g., the eNodeB) to evaluate the uplink and downlink separately when deciding whether a terminal's data traffic shall be moved from one RAN to another RAN. For example, a terminal that is generating a lot of uplink traffic may not be offloaded from an overloaded LTE node if the LTE load is mostly in downlink and not in uplink, and vice versa.

Another example where the UL/DL traffic distribution of the terminal 500 could be used for optimal steering is to consider the uplink throughput towards the Wi-Fi and LTE networks. Due to the small coverage area of the Wi-Fi cell as compared to an LTE cell, it can be expected that the terminal 500 will be able to communicate to the Wi-Fi AP with low power as compared to the LTE eNB. That is, it might be possible for the terminal 500 to have a better uplink connection to the Wi-Fi AP, while the downlink from the LTE is better. Thus, if a terminal's traffic is more heavy in the uplink than in the downlink, it might be beneficial to offload it to the Wi-Fi, even though the downlink signal level that is normally used to make offloading decisions could indicate otherwise.

A sixth communication status parameter is the type of traffic with respect to the second wireless network. Different types of traffic may have different characteristics making it more suitable to be communicated in one wireless network than the other. Furthermore, different types of traffic may have different priorities. And a proper wireless network may be selected for the terminal 500 based on the priority and the capability of the wireless networks.

A seventh communication status parameter is a service quality with respect to the second wireless network. The service quality is useful information as a measure of user satisfaction in the second wireless network. The understanding of user satisfaction may be used to decide which wireless network that should serve the user. An unsatisfied user in the second wireless network may be steered to the first wireless network if better service quality is predicted. The service quality may be measured in the terminal 500. While the contents of the report may be fixed in some embodiments, or determined by the mobile terminal 500 in others (such as based on the current status of the mobile terminal), in still other embodiments the network can indicate to the terminal 500 which information should be included in the report and the mobile terminal 500 thus receives information specifying the content of the report to be assembled The network may avoid indicating some information elements that are not necessary for the network to know, thereby reducing unnecessary signaling overhead.

Triggering conditions for reporting in terminal

There is also a need for knowing when to assemble the report discussed above. Examples of when to assemble the report are outlined below.

A first trigger of a reporting event is sending of a service request to the first wireless network. In some embodiments, the terminal 500 may send the information to the network when the terminal requests a service i.e. sending a service request. The network may then, based on knowledge about the current load of the system as well as the received information about the terminal, decide whether the terminal's service shall be carried over LTE or over Wi-Fi. For example, a service request is received by a terminal 500 which has Wi-Fi access when the LTE base station experiences high load - the network may not admit the terminal 500 and/or may admit it but schedule it with less resources and/or may order it to carry the service over Wi-Fi.

A second trigger of a reporting event is the connection or disconnection to the second wireless. The terminal 500 may send the information to the LTE network upon connection or disconnection to a Wi-Fi access point. This alternative allows for the LTE network to get notified immediately whenever the terminal 500 connects and disconnects to Wi-Fi, even in the case where the mobile terminal 500 has the main control regarding whether to connect to Wi-Fi or not, and the LTE network may consider this information in, for example, scheduling.

A third trigger of a reporting event is a request for a report received from the first wireless network. The terminal 500 may also send the information to the network upon reception of explicit request from the network. In some use cases, the terminal 500 may not know when the network needs the report and hence the network needs to request the terminal 500 to transmit a report. The network may indicate in the request the wanted content of the report. For example, the network may need to get reports of the amount of data transmitted over Wi-Fi more often than it needs to get reports of the experienced throughput. It could then request the terminal 500 to report certain information while avoiding some other information which would avoid unnecessary signaling overhead. Combinations of the above mentioned triggering conditions are also possible.

According to above discussed mechanisms, in some embodiments the network may request the terminal 500 to send a connection status report. There are several scenarios when this is expected to be beneficial.

The LTE network may not be able to provide good enough service to all the terminals and therefore would try to offload data traffic from one or more terminals from LTE to Wi-Fi. To do good offloading of the LTE network and maintaining good service quality for the terminals in the system, the LTE network may need to consider up-to-date information about the terminals Wi-Fi status. The network may then request one or more terminals to report this information. Note that the offloading may affect a terminal 500 only partially if it supports dual LTE-Wi-Fi connectivity (e.g. a terminal could still have some services keep running over LTE and offload some others to Wi-Fi).

Mobile terminal and network node techniques

Figure 3 is a process flow diagram illustrating an example method implemented by a mobile terminal 500 capable of operating in at least a first RAN and a second RAN, such as in an LTE network and a Wi-Fi network.

As shown at block 310, the illustrated method begins with receiving information that specifies all or part of the report contents, from the first RAN, e.g., from an eNodeB. This operation is shown in a dashed box in Figure 3, to indicate that this may not occur in all embodiments or in all circumstances. As discussed above, for example, all or part of the contents may be determined by the mobile terminal, based on current conditions, or may be specified by an industry standard. It also possible that triggering conditions may be received from the first RAN specifying when to trigger a reporting event. The mobile terminal 500 may then send a report that includes the specified contents when the trigger of the reporting event is fulfilled. As shown at block 320, the mobile terminal 500 detects a trigger of a reporting event i.e. reporting trigger event. This may be a local event, in some embodiments and/or circumstances, such as a locally generated service request as described above. In some cases, the trigger event may be a connection or disconnection to the second RAN (e.g., a Wi-Fi access point). In still other embodiments and/or circumstances, the trigger event may be the receiving of an explicit report request from the first RAN. Note that in some cases a report request from the first RAN may specify all or part of the contents of the requested report. As shown at block 330, the mobile terminal 500 assembles the report, including any combination of the parameters suggested above. That is, assembling a report in response to detecting the trigger of the reporting event, wherein the report comprises information of a connection status of the mobile terminal 500 with respect to the second wireless network. In some cases, of course, all or part of the specific contents (i.e., the specific parameters to include) are specified by the information received by the mobile terminal 500 from the first RAN.

As indicated at block 340, the mobile terminal 500 then transmits the report to the first RAN (e.g., to an LTE eNodeB). Although not shown in Figure 3, depending on the contents of the report and the conditions at the first RAN, the mobile terminal 500 may subsequently receive an order to steer its traffic to the second RAN, for example, or may receive scheduling grants that have been prioritized or de-prioritized in response to the report.

Figure 4 is a process flow diagram illustrating a complementary example method implemented by a network node in a first RAN, wherein the network node is generally configured to control one or more mobile terminals capable of operating in (at least) the first RAN and a second RAN, such as in an LTE network and a Wi-Fi network. The method may be carried out in a base station, such as an eNodeB in an LTE network, for example. However, it may also be carried out by another node in a network, such as a scheduling node or controller node that is separate from a radio base station, in which case communication with the mobile terminal 500 is typically carried out via a radio base station.

As shown at block 410, the illustrated method begins with sending information that specifies all or part of the desired report contents to one or more mobile terminals. This operation is shown in a dashed box in Figure 4, to indicate that this may not occur in all embodiments or in all circumstances. As discussed above, for example, all or part of the contents may be determined by the mobile terminal, based on current conditions, or may be specified by an industry standard.

As shown at block 420, the network node sends a request for a report, i.e. a report request, to one or more mobile terminals. Note that information specifying all or part of the report contents may be combined with a report request, in some embodiments. Again, this operation is shown in a dashed box in Figure 4, to indicate that this may not occur in all embodiments or in all circumstances. In some cases, for example, reports might only be sent by mobile terminals in response to other trigger events detected by the mobile terminals. In some embodiments, the mobile terminals may send reports in response to both explicit report requests sent by the network and other trigger events. As shown at block 430, the network node receives a report from one or more mobile terminals, the report for each mobile terminal 500 characterizing a connection status for the mobile terminal 500 with respect to a second RAN, such as a Wi-Fi network. The report may contain any or all of the parameters discussed earlier. As indicated at block 440, the network node evaluates the one or more reports, e.g., in conjunction with information about conditions at the first RAN, such as network or base station loading conditions. Responsive to this evaluation and depending on the information conveyed by the reports, the network node may proceed by steering traffic for one or mobile terminals to or from the second RAN, or by prioritizing scheduling for one or more mobile terminals, or both. In some cases, depending on the contents of the report the network node may for example transmit an order to the one or more mobile terminals to disconnect from or connect to the second wireless network. Alternatively the network node may transmit scheduling grants to the mobile terminal that the mobile terminal 500 has been prioritized or de-prioritized in response to the report. This is shown at block 450.

Several of the techniques and methods described above may be implemented using radio circuitry and electronic data processing circuitry provided in a terminal. Figure 5 illustrates features of an example terminal 500 according to several embodiments of the present disclosure. Terminal 500, which may be a UE configured for operation with an LTE network (E-UTRAN) and that also supports Wi-Fi, for example, comprises a transceiver unit 520 for communicating with one or more base stations as well as a processing circuit 510 for processing the signals transmitted and received by the transceiver unit 520. Transceiver unit 520 includes a transmitter 525 coupled to one or more transmit antennas 528 and receiver 530 coupled to one or more receiver antennas 533. The same antenna(s) 528 and 533 may be used for both transmission and reception. Receiver 530 and transmitter 525 use known radio processing and signal processing components and techniques, typically according to a particular telecommunications standard such as the 3GPP standards for LTE. Note also that transmitter unit 525 may comprise separate radio and/or baseband circuitry for each of two or more different types of radio access network, such as radio/baseband circuitry adapted for E-UTRAN access and separate radio/baseband circuitry adapted for Wi-Fi access. The same applies to the antennas - while in some cases one or more antennas may be used for accessing multiple types of networks, in other cases one or more antennas may be specifically adapted to a particular radio access network or networks. Because the various details and engineering tradeoffs associated with the design and implementation of such circuitry are well known and are unnecessary to a full understanding of the disclosure, additional details are not shown here.

More specifically, the mobile terminal 500 described above may be used for communicating information to a first wireless network of the mobile terminal's connection status to a second wireless network. The processing circuit 510 is configured to detect a trigger of a reporting event and further configured to assemble a report in response to a detected trigger of the reporting event, wherein the report comprises information of a connection status of the mobile terminal 500 with respect to the second wireless network. The transmitter 525 is configured to transmit the report to the first wireless network

The detection may also be performed by a detection module 570 for detecting the trigger of the reporting event. In turn the assembling may be performed by an assembling module 580 for assembling the report as described above. All modules, e.g. detection module 570 and assembling module 580 may be implemented as a computer program running on the processor or made to use by dedicated hardware such as an ASIC.

The mobile terminal 500 may also comprise a receiver 530. The receiver may be configured for receiving information specifying the content of the report to be assembled. Processing circuit 510 comprises one or more processors 540 coupled to one or more memory devices 550 that make up a data storage memory 555 and a program storage memory 560. Processor 540, identified as CPU 540 in Figure 5, may be a microprocessor, microcontroller, or digital signal processor, in some embodiments. More generally, processing circuit 510 may comprise a processor/firmware combination, or specialized digital hardware, or a combination thereof. Memory 550 may comprise one or several types of memory such as read-only memory (ROM), random-access memory, cache memory, flash memory devices, optical storage devices, etc. Because terminal 500 supports multiple radio access networks, processing circuit 510 may include separate processing resources dedicated to one or several radio access technologies, in some embodiments. Again, because the various details and engineering tradeoffs associated with the design of baseband processing circuitry for mobile devices are well known and are unnecessary to a full understanding of the disclosure, additional details are not shown here.

Typical functions of the processing circuit 510 include modulation and coding of transmitted signals and the demodulation and decoding of received signals. In several embodiments of the present disclosure, processing circuit 510 is adapted, using suitable program code stored in program storage memory 560, for example, to carry out one of the techniques described above for access network selection. Of course, it will be appreciated that not all of the steps of these techniques are necessarily performed in a single microprocessor or even in a single module.

Similarly, several of the techniques and processes described above can be implemented in a network node, such as an eNodeB. Figure 6 is a schematic illustration of a network node 600 in which a method embodying any of the presently described network-based techniques can be implemented. A computer program for controlling the node 600 to carry out a method of the present disclosure is stored in a program storage 630, which comprises one or several memory devices. Data used during the performance of a method of the present disclosure is stored in a data storage 620, which also comprises one or more memory devices. During performance of a method of the present disclosure, program steps are fetched from the program storage 630 and executed by a Central Processing Unit (CPU) 610, retrieving data as required from the data storage 620. Output information resulting from performance of a method of the present disclosure can be stored back in the data storage 620, or sent to an Input/Output (I/O) interface 640, which includes a network interface (not shown) for sending and receiving data to and from other network nodes and which may also include a radio transceiver 650 for communicating with one or more terminals.

Accordingly, in various embodiments of the disclosure, processing circuits, such as the CPU 610 in Figure 6, are configured to carry out one or more of the techniques described in detail above. Likewise, other embodiments include radio network controllers including one or more such processing circuits. In some cases, these processing circuits are configured with appropriate program code, stored in one or more suitable memory devices, to implement one or more of the techniques described herein. Of course, it will be appreciated that not all of the steps of these techniques are necessarily performed in a single microprocessor or even in a single module. More specifically, the network node 600 described above may be used to control one or more mobile terminals capable of operating in a first wireless network and a second wireless network. The transceiver 650 is configured to receive a report from the one or more mobile terminals 500, 501 , wherein the report for each mobile terminal comprises information of a connection status of the mobile terminal with respect to a second wireless network.

The processing circuit is configured to evaluate the one or more reports and further configured to steer traffic for the one or more mobile terminals to or from the second wireless network based on the evaluated one or more reports or to prioritize scheduling for the one or more mobile terminals based on the evaluated one or more reports. The evaluation may also be performed by an evaluation module 660 for evaluating the one or more reports. In turn the steering of traffic described above may be performed by a steering module 670 and the prioritization of traffic described above may be performed by a prioritization module 680.

All modules, e.g. evaluation module 660, steering module 670 and prioritization module 680 may be implemented as a computer program running on the processor made to use by dedicated hardware such as an ASIC . The transceiver 650 may further be configured to send information to the one or more mobile terminals specifying the content of the report to be received. The transceiver may further be configured to send a request for the report to the one or more mobile terminals. The disclosed techniques make it possible for a first RAN to have information regarding a terminal's connection to a second RAN, regardless of the level of integration between the first and second RAN. This information may be considered by the first RAN, for example, when performing scheduling, deciding whether a terminal's connection (to the first or the second RAN) shall be maintained or terminated, whether a terminal shall communicate over the first or second RAN, etc.

It will be appreciated by the person of skill in the art that various modifications may be made to the above described embodiments without departing from the scope of the present disclosure. For example, it will be readily appreciated that although the above embodiments are described with reference to parts of a 3GPP network, an embodiment of the present disclosure will also be applicable to like networks, such as a successor of the 3GPP network, having like functional components. Therefore, in particular, the terms 3GPP and associated or related terms used in the above description and in the enclosed drawings and any appended claims now or in the future are to be interpreted accordingly.

Examples of several embodiments of the present disclosure have been described in detail above, with reference to the attached illustrations of specific embodiments. Because it is not possible, of course, to describe every conceivable combination of components or techniques, those skilled in the art will appreciate that the present disclosure can be implemented in other ways than those specifically set forth herein, without departing from essential characteristics of the disclosure. The present embodiments are thus to be considered in all respects as illustrative and not restrictive.

Claims

1 . A method in a mobile terminal (500) for transmitting information to a first wireless network (600) of the mobile terminal's connection status with respect to a second wireless network (601 ), the method comprising,

detecting (320) a trigger of a reporting event,

assembling (330) a report in response to detecting the trigger of the reporting event, wherein the report comprises information of a connection status of the mobile terminal (500) with respect to the second wireless network, and

transmitting (340) the report to the first wireless network

2. The method according to claim 1 wherein the connection status indicates a radio status of the mobile terminal (500).

3. The method according to claim 2 wherein the radio status indicates at least one of:

a capability of the mobile terminal (500) of communicating with the second wireless network,

whether a radio in the mobile terminal (500) for communicating with the second wireless network is on or off,

a version of the communication protocol used in the mobile terminal (500) for communicating with the second wireless network, and

whether the mobile terminal (500) is associated or connected to the second wireless network.

4. The method according to any of claims 1 -3 wherein the connection status comprises a communication status of the mobile terminal (500).

5. The method according to claim 4 wherein the communication status comprises at least on of :

a throughput with respect to the second wireless network,

a bit rate with respect to the second wireless network,

a latency with respect to the second wireless network, an amount of data transmitted or received with respect to the second wireless network,

an uplink-downlink traffic distribution with respect to the second wireless network,

a type of traffic with respect to the second wireless network, and

a service quality with respect to the second wireless network

6. The method according to any of claims claim 1 -5 wherein the method further comprising receiving (310) information from the first wireless network specifying the content of the report to be assembled.

7. The method according to any of claims 1 -6 wherein the trigger of a reporting event is at least one of:

a sending of a service request to the first wireless network,

a connection or disconnection to the second wireless network, and

a receiving of a request for the report from the first wireless network

8. The method according to any of claims 1 -7 wherein the first wireless network is a 3GPP wireless network and the second wireless network is a Wi-Fi network or vice versa.

9. A method in a network node (600) for controlling one or more mobile terminals (500, 501 ) capable of operating in a first wireless network and a second wireless network the method comprising

receiving (430) a report from the one or more mobile terminals (500, 501 ), wherein the report for each mobile terminal comprises information of a connection status of the mobile terminal with respect to a second wireless network, and

evaluating (440) the one or more reports, and

steering traffic (450) for the one or more mobile terminals (500, 501 ) to or from the second wireless network based on the evaluated one or more reports or prioritizing scheduling (450) for the one or more mobile terminals (500, 501 ) based on the evaluated one or more reports.

10. The method according to claim 9, further comprising sending (410) information to the one or more mobile terminals (500, 501 ) specifying the contents of the one or more reports.

1 1 . The method according to any of claims 9-10, further comprising sending (420) one or more requests for the reports to the one or more mobile terminals (500, 501 )

12. The method according to claim 9-1 1 wherein steering traffic (450) to or from the one or more mobile terminals (500, 501 ) comprises ordering at least one of the one or more mobile terminals to disconnect from or connect to the second wireless network.

13. The method according to any of claims 9-12 wherein the connection status indicates a radio status of the mobile terminal (500, 501 ).

14. The method according to claim 13 wherein the radio status indicates at least one of: a capability of the mobile terminal (500, 501 ) of communicating with the second wireless network,

whether a radio in the mobile terminal (500, 501 ) for communicating with the second wireless network is on or off,

a version of the communication protocol used in the mobile terminal (500, 501 ) for communicating with the second wireless network,

whether the mobile terminal (500, 501 ) is associated or connected to the second wireless network.

15. The method according to any of claims 9-14 wherein the connection status indicates a communication status of the mobile terminal (500, 501 ).

16. The method according to claim 15 wherein the communication status indicates at least on of :

a throughput with respect to the second wireless network, a bit rate with respect to the second wireless network,

a latency with respect to the second wireless network,

an amount of data transmitted or received with respect to the second wireless network,

a type of traffic with respect to the second wireless network, and

a service quality with respect to the second wireless network.

17. A mobile terminal (500) for communicating information to a first wireless network of the mobile terminal's connection status with respect to a second wireless network, the mobile terminal (500) comprising,

a processing circuit (510), and

a transmitter (525)

wherein the processing circuit (510) is configured to detect a trigger of a reporting event and further configured to assemble a report in response to that the trigger of the reporting event is detected, wherein the report comprises information of a connection status of the mobile terminal (500) with respect to the second wireless network, and

wherein the transmitter (525) is configured to transmit the report to the first wireless network.

18. The mobile terminal according to claim 17 wherein the connection status indicates a radio status of the mobile terminal (500).

19. The mobile terminal (500) according to claim 18 wherein the radio status indicates at least one of:

a version of the communication protocol used in the mobile terminal (500) for communicating with the second wireless network, and whether the mobile terminal (500) is associated or connected to the second wireless network.

20. The mobile terminal (500) according to any of claims 17-19 wherein the connection status comprises a communication status of the mobile terminal (500).

21 . The mobile terminal (500) according to claim 20 wherein the communication status comprises at least on of :

a throughput with respect to the second wireless network, and

a bit rate with respect to the second wireless network, and

a latency with respect to the second wireless network, and

an amount of data transmitted or received with respect to the second wireless network, and

an uplink-downlink traffic distribution with respect to the second wireless network, and

a type of traffic with respect to the second wireless network, and

a service quality with respect to the second wireless network

22. The mobile terminal (500) according to any of claims claim 17-21 wherein the mobile terminal (500) further comprises a receiver (530) configured to receive information specifying the content of the report to be assembled.

23. The mobile terminal (500) according to any of claims 17-21 wherein the trigger of a reporting event is at least one of:

a sending of a service request to the first wireless network, and

a connection or disconnection to the second wireless network, and

a receiving of a request for the report received from the first wireless network

24. The mobile terminal (500) according to any of claims 17-23 wherein the first wireless network is a 3GPP wireless network and the second wireless network is a Wi- Fi network or vice versa.

25. A network node (600) configured to control one or more mobile terminals capable of operating in a first wireless network and a second wireless network, the network node comprising

a processing circuit (610), and

a transceiver (650)

wherein the transceiver (650) is configured to receive a report from the one or more mobile terminals, wherein the report for each mobile terminal comprises information of a connection status of the mobile terminal with respect to a second wireless network, and

wherein the processing circuit (610) is configured to evaluate the one or more reports and further configured to steer traffic for the one or more mobile terminals to or from the second wireless network based on the evaluated one or more reports or to prioritize scheduling for the one or more mobile terminals based on the evaluated one or more reports.

26. The network node according to claim 25, wherein the transceiver (650) is further configured to send information to the one or more mobile terminals specifying the contents of the one or more reports

27. The network node according to any of claims 25-26, wherein the transceiver (650) is further configured to send one or more requests for the reports to the one or more mobile terminals.

28. The network node according to any of claims 25-27 wherein steering traffic to or from the one or more mobile terminals comprises ordering at least one of the one or more mobile terminals to disconnect from or connect to the second wireless network.

29. The network node according to any of claims 25-28 wherein the connection status indicates a radio status of the mobile terminal.

30. The network node according to claim 29 wherein the radio status indicates at least one of:

a capability of the mobile terminal of communicating with the second wireless network,

whether a radio in the mobile terminal for communicating with the second wireless network is on or off, a version of the communication protocol used in the mobile terminal for communicating with the second wireless network, and

whether the mobile terminal is associated or connected to the second wireless network.

31 . The network node according to any of claims 25-30 wherein the connection status indicates a communication status of the mobile terminal.

32. The network node according to claim 25-31 wherein the communication status indicates at least on of :

a throughput with respect to the second wireless network,

a bit rate with respect to the second wireless network,

a latency with respect to the second wireless network,

a uplink-downlink traffic distribution with respect to the second wireless network,

a type of traffic with respect to the second wireless network, and

a service quality with respect to the second wireless network