CN101828362B - Packet in communication network forwards - Google Patents

Abstract

There is provided a kind of for rearranging the solution that data transmit in communication network.Thus, in the network node that the first logic connects and the second logic of being associated with the second user terminal is connected being associated with first user terminal in communication network, reception is connected about with the first logic and comes from the packet of first user terminal, and wherein this packet is addressed to the second user terminal.Then, network node checks that the first logic connects and the second logic connects the intermediate network node shared, and if it have detected that share intermediate network node, then arranges shortcut between first and second logic connects by intermediate network node.

Description

Packet Forwarding in Telecom Networks

technical field

The present invention relates to the transport of data packets in a telecommunications network comprising wired and wireless communication links within logical connections established in the telecommunications network.

Background technique

In order to provide wireless broadband access and high data transfer rates in residences, base stations that are deployed in residences and communicate with user terminals have been available for some time. Wireless base stations or routers that communicate with user terminals according to the IEEE 802.11x standard (Wireless Local Area Network or Wi-Fi) have been available for years, but dedicated base stations that communicate according to cellular radio telecommunication standards have recently entered the world. Private base stations are generally associated with uncoordinated deployments, ie the network infrastructure and coverage of the cellular telecommunication system is not based on the geographical deployment of private base stations. Private base stations can go by many names, including femto base station, femto node B, femto eNode B or simply home access, and have become a hot topic of discussion within the operator and manufacturer community.

Private base stations are consumer goods for uncoordinated deployments not under the control of the operator of the cellular network. Private base stations may be located on a different frequency layer than public base stations. For example, one frequency layer of 5 MHz in W-CDMA (Wideband Code Division Multiple Access) may be used in public cells, while a separate frequency layer is used for private deployments, with private base stations also potentially intended as public capacity enhancement layers.

It can be assumed that an end user buys an economical private base station and installs it as a physical entity in his house. The private base station then provides coverage and service to user equipment registered by the owner of the private base station. Private base stations can be connected towards the Internet via DSL (Digital Subscriber Line) and via the operator's core network. An operator's core network typically includes one or more network nodes providing IP (Internet Protocol) connectivity to user equipment. In more detail, data packets sent/received by the user equipment are transferred between the user equipment and a peer entity (eg an Internet server or another user equipment) via one or more network nodes.

Contents of the invention

According to an aspect of the invention, a solution is provided for rearranging and optimizing data transfer within a telecommunications network in order to increase network capacity.

According to an aspect of the invention, a method as claimed in independent claims 1 and 35 is provided.

According to a further aspect of the invention, there is provided an apparatus as claimed in independent claims 16, 31, 32 and 34.

According to a further aspect of the present invention, a computer program product as claimed in independent claim 33 is provided.

Embodiments of the invention are defined in the dependent claims.

Description of drawings

Embodiments of the invention are described below, by way of example only, with reference to the following drawings, in which:

Figure 1 illustrates an example of a network architecture for providing IP services to user equipment served by a private base station;

Figure 2 illustrates another example of a network architecture for providing IP services to user equipment;

Figure 3 illustrates an embodiment for providing short-cuts for data transfers within private base stations of the network shown in Figure 1;

Figure 4 illustrates an embodiment for providing shortcuts for data transfer in network elements of the network shown in Figure 2;

Figure 5 illustrates a signaling diagram for providing shortcuts for data transfer in intermediate network nodes according to an embodiment of the present invention;

Figure 6A illustrates the format of a data packet transmitted by a user terminal;

Figure 6B illustrates the format of the data packet of Figure 6A after encapsulation for tunneling;

Figure 7 illustrates a block diagram of a device according to an embodiment of the invention; and

Fig. 8 is a flowchart illustrating a process for rearranging data transmissions in a telecommunications network according to an embodiment of the present invention.

detailed description

The following examples are exemplary. Although the specification may refer to "an", "an" or "some" embodiments in several places, this does not necessarily mean that each such reference refers to the same embodiment or that the feature is only applicable to a single embodiment. Individual features of different embodiments may also be combined to provide other embodiments.

The general architecture of a mobile telecommunications network that provides wireless voice and packet-switched data transfer services to user terminals through one or more dedicated base stations connected to the telecommunications network is illustrated in Figure 1 . Figure 1 is a simplified system architecture showing only some elements and functional entities of the network, all of which are logical units whose implementation may differ from the one shown. It is clear to a person skilled in the art that the mobile telecommunication system also includes other functions and structures.

A mobile telecommunications network may comprise a fixed part comprising a plurality of network nodes interconnected by wired connections and configured to carry data associated with user terminals served by the network. The network of the mobile telecommunications system may provide connections to other networks such as the Internet 150 . The mobile telecommunications network also includes one or more private base stations 124, 126, 128 connected to at least one of the network nodes and extending coverage of the private base stations 124, 126, 128 The user terminals 132 to 142 within provide a wireless radio connection. Coverage areas are often referred to as cells. User terminals 132 and 134 illustrated in Figure 1 are served by a first private base station 124, user terminal 136 is served by a second private base station, and user terminals 138, 140 and 142 are served by a third private base station.

The radio interface between the private base stations 124 to 128 and the user terminals 132 to 142 may be implemented according to standardized specifications of the public mobile telecommunication system. In more detail, the radio interface may be a long-term evolution of a 3rd generation mobile communication system, such as the Universal Mobile Telecommunications System (UMTS) standardized within the 3rd Generation Partnership Project (3GPP), and has a common common base station infrastructure ( not shown). However, the radio interface may be implemented according to the specifications of another mobile telecommunication system having a fixed infrastructure of public base stations connected to the operator's fixed network.

The distinction between public and private base stations is defined at this stage. The difference between a private base station and a public base station is that a public base station can (under normal conditions) be accessed by any user terminal located within the coverage area of the public base station. A private base station, on the other hand, is the property of an individual user and is therefore dedicated to providing radio connections to a limited number of user terminals registered with the private base station. In other words, the owner of the private base station may configure the private base station to provide radio connections only to user terminals defined by their IDs and/or SIMs (Subscriber Identity Modules) attached to these user terminals.

The private base stations 124, 126, 128 illustrated in Figure 1 are connected to the wired network by xDSL (Digital Subscriber Line) connections. An xDSL connection may eg be an Asynchronous DSL connection (ADSL) or a Very High Speed DSL (VDSL) connection. The private base stations 124, 126, 128 may be connected to a DSL access multiplexer 122 located in the xDSL access network 120 close to the private base stations and configured to connect the xDSL access Multiple DSL connections from the incoming network to other parts of the telecommunications network. In the exemplary architecture of FIG. 1, a DSL access multiplexer 122 connects a private base station to the regional access network 110 of the operator managing the telecommunications network. In particular, the DSL access multiplexer 122 terminates the DSL connection and forwards the data packets towards the broadband access server 112, which aggregates the data packets transmitted across multiple user connections and directs these data packets towards their actual destination address forwarding. The broadband access server 112 may aggregate user connections also from other DSL access networks than the xDSL access network 120 illustrated in FIG. 1 . DSL access multiplexer 122 and broadband access server 112 are elements of common prior art networks, and their operation will therefore not be discussed in more detail in this specification.

The operator's IP (Internet Protocol) backbone 100 network includes a terminating network node 104 , which terminates the logical connections of the user terminals 132 to 142 . A logical connection may eg be an IP connection established between a given user terminal and the terminating network node 104 . In the field of mobile telecommunications networks, logical connections may also be referred to as bearer services. The terminating network node 104 is referred to as a Packet Data Network (PDN) System Architecture Evolution (SAE) Gateway (GW) node in this specification, ie PDN SAE GW for short, but the features of the terminating network node 104 are not limited thereto. The PDN SAE GW 104 is a standard network element of the long-term evolution (LTE) packet switching network and the system architecture evolution (SAE) 3.9th generation mobile communication system.

In other words, when any of the user terminals 132 to 142 requests a packet data transfer service from a peer entity (either to an Internet server or to a user entity), a logical connection is established between the user terminal and the PDN SAE GW 104 (IP connection). When establishing an IP connection, PDN SAE GW 104 provides the user terminal with an IP address to be used as a source or destination address for data packets communicated between PDN SAE GW 104 and the user terminal. The PDN SAE GW 104 serves as an IP point of attachment for mobile user terminals, which may move within the radio access network of the mobile telecommunication system. In other words, data packets may be transferred between the mobile user terminal and the PDN SAE GW 104 through different base stations and sub-networks according to the movement of the mobile user terminal.

PDN SAE GW 104 provides connectivity to the Internet 150 and other external networks. The IP backbone 100 also includes a mobility management entity 102 that handles mobility issues for user terminals served by the network. Among other functions, the mobility management entity 102 implements the selection of a subnetwork according to the current location of the user terminal and controls the PDN SAE GW 104 to transmit the data packets of the user terminal over the appropriate subnetwork.

At least part of the logical connection between the terminating network node 104 and the user terminal may be provided via a tunneled connection. In the example illustrated in Figure 1, a tunneled connection is provided between the third private base station 128 and the terminating network node 104, ie the PDN SAE GW. Similar tunneled connections may be provided between the other private base stations 124 and 126 and the terminating network node 104, although not shown in FIG. 1 . Tunneling can be implemented according to the GPRS (General Packet Radio Service) Tunneling Protocol (GTP), which is used, for example, in GSM (Global System for Mobile Communications) and UMTS networks. GTP is assumed to be a generally known tunneling protocol and is therefore not described in more detail here.

The originating network node of the tunneled connection (eg private base station 128 in FIG. 1 ) encapsulates IP data packets to be transmitted over the IP connection into GTP packets according to the GTP protocol. In other words, the origin network node arranges the IP data packet into the payload part of the GTP packet, and generates GTP header information for the data packet, and inserts the header information into the header part of the GTP packet. The GTP packet is then transmitted via the GTP tunnel to the end point network node of the GTP tunneled connection (eg PDN SAE GW 104 ), where the GTP packet is decapsulated, ie the payload part (IP packet) is extracted from the GTP packet. The IP packets are then forwarded towards the end point of the IP connection, or extracted at the end point network node if the end point of the tunneled connection is also an end point of the IP connection.

As mentioned above, an IP connection is created between each user terminal 132 to 142 and the PDN SAE GW 104 . Part of this IP connection is arranged on a radio bearer between the user terminal and the serving private base station. In the example of Fig. 1, the rest of the IP connection is arranged as a GTP tunneled connection between the private base station and the network node 104 (ie PDN SAE GW) terminating the IP connection. It should be noted at this stage that parts of the logical connection may also be implemented as non-tunneled connections between network nodes between the user terminals 132 to 142 and the terminating network node 104 . A similar connection can be established for each user terminal 132 to 142, ie the PDN SAE GW 104 acts as a terminating network node for all IP connections of the user terminals 132 to 142, ie all data packets of the user terminal are transferred via the PDN SAE GW. This can create problems in some situations.

Assume that the first user terminal 138 served by the third private base station 128 has established a first logical connection (eg IP connection) with the PDN SAE GW node 104, wherein the PDN SAE GW node 104 acts as the terminating network node of the logical connection. Similarly, a second user terminal 142 served by the same private base station 128 has established a second logical connection with the PDN SAE GW 104 . The first user terminal 138 then has data packets to be transmitted to the second user terminal 142 . Since all IP traffic of user terminals 138 and 142 is carried over the terminating network node 104 of the logical connection, the data packets must first be transmitted to the terminating network node 104 via the first logical connection. Then, the terminating network node 104 extracts the destination information contained in the header of the IP data packet, obtains the knowledge that the destination address is equal to the IP address of the second terminal 142, and passes through the second logical The connection sends the data packet towards the second user terminal 142 through which the data packet was sent towards the terminating network node 104 via the first logical connection via these intermediate network nodes. Thus, data packets are unnecessarily transmitted through the same intermediate network node, thereby wasting network resources, causing load, reducing the data rate and increasing the latency of each connection using the same intermediate network node as the first and second logical connections time (especially in the case of asynchronous DSL connections). Similar problems may be self-evident with respect to connections between user terminals served by public base stations. At least part of the problem is tunneling. The intermediate network nodes of the tunneled connection simply forward the data packets to the end points of the tunneled connection. Thus, the intermediate nodes are ignorant of the fact that it is possible to optimize the routing of data packets encapsulated for tunneled connections.

According to an embodiment of the invention, data packets originating from the first user terminal and related to the first logical connection which may comprise at least one tunneled connection are received by an intermediate network node of the first logical connection in the telecommunications network. The intermediate network node compares the destination address of the data packet with a service list comprising the addresses of the user terminals through which the data packet is conveyed. If the destination address of the data packet matches the address of the second user terminal included in the service list, the intermediate network node forwards the received data packet towards the second user terminal instead of via the longer route pair via the terminating network node. Data packets are relayed.

Figure 3 illustrates an example of providing short-cuts for data packets in the telecommunications network of Figure 1 . In this example, the intermediate network node is the third private base station 128 . Consider again the case where the first user terminal 128 sends a data packet destined for the second user terminal 142 . According to a conventional solution, the data packets are first conveyed via the third private base station 128 via the first logical connection towards the terminating network node 300, in this example the PDN SAE GW 104. The terminating network node 300 then associates the data packet with the second logical connection and sends the data packet to the second user terminal 142 via the second logical connection.

According to an embodiment of the present invention, the private base station 128 may store the IP addresses of the user terminals served by the private base station 128 . Said IP addresses may be stored in a service list comprising IP addresses of user terminals served by the private base station. In some cases, a user terminal may have multiple IP addresses, where each IP address is associated with a different logical connection. In such a case, the service list may include all IP addresses of the user terminals.

Upon receiving a data packet, private base station 128 may check the destination address of the data packet and check the service list for a match with the destination address. If the service list includes an IP address that matches the destination address of the data packet, private base station 128 may connect the first logical connection with the second logical connection to provide a shortcut between the first user terminal and the second user terminal connect. Thereafter, the private base station 128 may convey the data packet directly to the second user terminal 128 without conveying the data packet through a longer route via the terminating network node 300 .

The embodiments described above are particularly advantageous in situations where user terminals served by a shared private base station exchange data packets. In such a case, the data transfer between the user terminals causes neither a significant load on the DSL access network 120, the regional access network 110, nor the IP backbone, since the private base station directs the downlink towards the receiving user terminal The link connection forwards received uplink data packets. In an alternative embodiment, the above mentioned procedures may be implemented in a common base station serving two user terminals exchanging data packets.

Figure 2 illustrates another embodiment of a network capable of supporting data packet simplification according to an embodiment of the present invention. Network elements with the same reference numbers as those in Figure 1 have similar functions.

FIG. 2 illustrates an additional network element called serving SAE GW node 214 . Serving SAE GW 214 carries IP traffic between user terminals 132-142 and the terminating network node (ie, PDN SAE GW 104). Serving SAE GW 214 may be capable of processing encapsulated data packets, eg, to analyze the encapsulated content of the data packets. Serving SAE GW node 214 may be connected between PDN SAE GW 104 and broadband access server 112 and located at the edge of regional access network 210 . In practice, data packets may be transmitted from the DSL access multiplexer 122 to the serving SAE GW node 214 through the broadband access server 112 . The PDN SAE GW can still function as an IP point of attachment for user terminals 132 to 142 served by private base stations 124 to 128 connected to the xDSL access network 120 . In other words, a logical connection can still be established between the user terminals 132 to 142 and the PDN SAE GW 104 .

The xDSL access network 120 may be similar to the xDSL access network illustrated in FIG. 1 . Data packet flows between user terminals 132 to 142 and the PDN SAE GW may be carried through the DSL access multiplexer 122 , the broadband access server 112 and the serving SAE GW node 214 . A tunneled connection may be provided between each private base station 124 - 128 and the serving SAE GW node 214 . Additionally, another tunneled connection may be provided between the serving SAE GW node 214 and the PDN SAE GW 104 . Tunneled connections can again be implemented according to the GPRS Tunneling Protocol (GTP).

In this embodiment, the serving SAE GW node 214 operates as an intermediate network node providing a shortcut for data packets transmitted between two of the user terminals 132-142. Figure 4 illustrates the provision of shortcuts between user terminals 132 and 136 in the network of Figure 2 which are served by different (private) base stations 124 and 126, respectively. As mentioned above, the intermediate network node 400 may be the serving SAE GW node 214 and the terminating network node 402 (ie the network node terminating the logical connection) may again be the PDN SAE GW 104 . This embodiment is particularly advantageous in case data packets are transferred between two user terminals served by different base stations. The base stations serving the user terminals between which a shortcut is provided may be private base stations, but at least one of said base stations may also be a public base station. In fact, all base stations can be common base stations.

Consider again the case where the first user terminal 132 and the second user terminal 136 have respectively established first and second logical connections with the terminating network node 402 . Logical connections may be referred to as IP connections, SAE bearer services, and the like. Similar to the embodiment described above with reference to FIG. 3 , the intermediate network node 400 may store the IP addresses of user terminals transmitting data packets via the intermediate network node 400 . IP addresses may be stored in service lists of the type described above. Upon receiving a data packet, the intermediate network node 400 may check the destination address of the data packet and check the service list for a match with the destination address. If the service list includes an IP address that matches the destination address of the data packet, the intermediate network node 400 may connect the first logical connection with the second logical connection for communication between the first user terminal 132 and the second user terminal 136 Shortcut connections are provided. Thereafter, the intermediate network node 400 may convey the data packet directly to the second user terminal 136 without conveying the data packet through a longer route via the terminating network node 402 .

The embodiment described above with reference to FIG. 4 is particularly advantageous in the sense that it provides centralized simplification for a larger number of user terminals than the embodiment described with reference to FIG. 3 . A much larger number of user terminals transmits their data packets through the serving SAE GW node than through a single dedicated base station, and thus this embodiment can provide data packet simplification for user terminals served by different base stations. Additionally, this embodiment can support simplification in case the user terminal is handed over due to a higher position in the network hierarchy.

The embodiments described above with reference to Figures 3 and 4 can naturally be combined to provide simplified flexibility. Assume a situation where two user terminals served by a common base station exchange data packets via a shortcut provided by the base station through an appropriate logical connection (radio bearer) connecting the user terminals. Then, one of the two user terminals moves further away from the base station, so that the user terminal is handed over to the other base station. Since the user terminal no longer uses the base station as a common node, the base station may no longer provide a shortcut. However, the user terminal may have another common node at a higher level in the network architecture, and this common node may be located between the user terminal and the network node terminating the logical connection of the user terminal. This common node may then arrange shortcuts for exchanging data between user terminals and may provide shortcuts as described above with reference to FIG. 4 . Thus, telecommunication according to this embodiment of the invention is still able to pass through an intermediate network node which is the nearest shared node of the user terminals (i.e. the nodes) provide shortcuts to optimize the routing of data packets.

In general, a solution is provided for providing a shortcut between two logical connections. On receiving a data packet associated with the first logical connection and received from the first user terminal in the network node, the destination address of the data packet is extracted from the received data packet. If it is detected that a data packet is addressed to the second user terminal and should be sent to the second user terminal via the second logical connection, it is checked whether there is an intermediate network node shared by the first and second logical connection. That is, it is checked whether there is a shared intermediate network node closer to the first and second user terminal in the network architecture than the network node terminating the first and second logical connection. If such an intermediate network node is detected, a shortcut between the first and second logical connection is established via the detected intermediate network node.

Embodiments for providing shortcuts are next described in more detail with reference to the signaling diagram illustrated in Figure 5 and the data packet formats illustrated in Figures 6A and 6B. Signaling diagram illustrating data packets between a network comprising a first user terminal UE1 sending data packets to a second user terminal UE2, a second user terminal UE2, intermediate network nodes arranged to provide a shortcut and a terminating network node flow, the terminating network node serving as an endpoint for a logical connection established between the terminating network node and the first user terminals UE1 and UE2. Both user terminals UE1 and UE2 may have established one or more logical connections with the terminating network node and thus have one or more IP addresses assigned by the terminating network node. The same IP address may of course be used for several or even all logical connections associated with a given user terminal. An intermediate network may be a network node between endpoints of a logical connection. It is assumed in this example that an intermediate network node is between the base station(s) serving the user terminals UE1 and UE2 and the terminating network node. It is further assumed that the intermediate network nodes send and receive data packets through tunneled connections. Tunneled connections are considered broadly in this specification to also include equivalent data carrying mechanisms such as Multiprotocol Label Switching (MPLS) or any other equivalent mechanism.

At S1, UE1 first sends a data packet addressed to UE2 to an intermediate network node. There may be several nodes between UE1 and the intermediate network node, although not illustrated in FIG. 5 . The format of the data packets sent by UE1 is illustrated in Fig. 6A. User terminals may transmit data packets as IP packets including header and payload data. The header may include an IP header with a length of 20 bytes and a transport and application protocol header with a length of 20 bytes. The IP header may include a 12-byte IPv4 header, which includes an IP version number, service type, error checksum bits, and the like. Obviously, the Ipv4 header can be replaced by the Ipv6 header if the network supports IP protocol version 6. Furthermore, the IP header includes a source address (IP address of UE1) and a destination address (IP address of UE2 to which the data packet is addressed). Transport and application protocol headers may include User Datagram Protocol (UDP) headers and Real-time Transport Protocol (RTP) headers, such as defining ports for not only source ports but also destination ports. The application port number of the port, and the real-time transport protocol (RTP) header includes a version number, a sequence number for identifying a data packet in a sequence of data packets, a time stamp for synchronization and measurement of packet arrival jitter, and the like. The source port address identifies the address of the application that initiated the session. The destination port correspondingly identifies the recipient address of the session.

UE data packets are received by a network node (not shown in Figure 5) acting as the origin of the tunneled connection. The network node formats received UE packets into a format suitable for transmission over the tunneled connection. If the tunnel connection is provided according to GTP, the reformatted data packets may have the format illustrated in Fig. 6B. A GTP tunneled data packet may include a header and a payload portion comprising the original data packet shown in FIG. 6A. In other words, the network node has encapsulated the data packet into the payload part of the GTP tunneled data packet to be transmitted over the tunneled connection. The header of the GTP tunneling data packet can include the above-mentioned similar Ipv4 header, source address and destination address, and UDP header, the difference is that the source address represents the IP address of the network node at the starting point of the tunnel connection, and the destination address Indicates the IP address of the network node at the end of the tunneled connection. In addition, the header of the GTP tunneled data packet includes a GTP header and an optional timestamp. The GTP header includes a Tunnel Endpoint Identifier (TEID) identifying the GTP tunnel through which the data packet will be transmitted. TEID can also be used as an identifier for a logical connection.

The network node then sends the GTP tunneled data packet towards the intermediate network node. When receiving a data packet, the intermediate network node analyzes the header information of the received data packet in S2. In more detail, the intermediate network node may read the destination address from the received data packet. The read destination address may be a destination address indicating the final destination of the payload of the data packet. That is, if the data packet is an encapsulated GTP tunneled data packet, the intermediate network node can examine the payload portion (ie the original user packet) for the final destination address. The intermediate network node may then compare the read destination address with a stored service list comprising the IP addresses of the user terminals carrying the data packets via the intermediate network node. If the destination address of the data packet matches an IP address stored in the service list, the intermediate network node detects the possibility of arranging a shortcut between the logical connections of UE1 and UE2. However, intermediate network nodes may not know at this stage which two logical connections should be connected to provide a shortcut. As mentioned above, UE1 and UE2 may have multiple logical connections, and the intermediate network node may not necessarily know which logical connection of UE2 relates to the logical connection of UE1 through which data packets are being transmitted.

Thus, the intermediate network node may read and store at least part of the header information of the received data packet at S2 and send the data packet towards the terminating network node at S3. In particular, an intermediate network node may read and store a 5-tuple of a data packet comprising source and destination IP addresses, a protocol identifier, and source and destination port numbers. The stored 5-tuple is used as the packet identifier for the data packet. Additionally, the intermediate network node may insert a shortcut preparation indicator into data packets sent to the terminating network node. The shortcut preparation indicator may inform the terminating network node that the intermediate network node is preparing a shortcut for the logical connection through which the data packet is being transmitted.

Conversely, the terminating network node knows which logical connections are mapped together, ie which uplink logical connection of UE1 is related to which downlink logical connection of UE2. Thus, the terminating network node sends the received data packets towards UE2 at S4 via the appropriate logical connection. Previously, the terminating network node may have decapsulated and re-encapsulated the received data packet according to the Tunneling Protocol (GTP) related to the logical connection with UE2. For example, the terminating network node may change at least the source and destination addresses and the TEID value of the header of the GTP tunneled data packet to correspond to the appropriate tunnel.

Furthermore, the terminating network node may extract the short-cut preparation indicator from the received data packet and check whether short-cut preparation is allowable. If the short-cut preparation is allowable, the terminating network node may insert information confirming the short-cut preparation into the data packets transmitted towards UE2. On the other hand, if short-cut provisioning is not permissible, the terminating network node may insert information denying short-cut provisioning into data packets transmitted towards UE2. Hence, the terminating network node may include a Shortcut Preparation Approve message or a Shortcut Preparation Reject message in the data packet. Alternatively, the shortcut preparation indicator and the acknowledgment/rejection may be transmitted as separate signaling information.

In embodiments in which the intermediate network node requests permission from the terminating network node to place short cuts, it is possible to selectively disable short cut provisioning if desired.

The intermediate network node receives the data packets from the terminating network node due to the transport of the data packets of the two interrelated logical connections through the intermediate network node. The intermediate network node may then extract information related to the short-cut preparation request. If the information indicates that the shortcut preparation was rejected by the terminating network node, the intermediate network node terminates the shortcut preparation and forwards to the terminating network node subsequent data packets received over the logical connection associated with the originally received data packet. On the other hand, if the information indicates that the terminating network node has approved the shortcut, the intermediate network node proceeds to arrange the shortcut between the two logical connections. The intermediate network node may then analyze the 5-tuple of the received data packet and detect that this 5-tuple matches a previously stored 5-tuple at S2. In other words, the intermediate network node detects that the data packet received from the terminating network node is the same data packet analyzed at S2. The intermediate network node then arranges a shortcut between the two logical connections at S5 by connecting the uplink direction of the first logical connection related to UE1 to the downlink direction related to the second logical connection of UE2.

Thereafter, the intermediate network node may send the data packets received from the terminating network node to UE2 at S6. Since the intermediate network node has arranged a shortcut between UE1 and UE2 for the service in which at least data is transferred from UE1 to UE2, the intermediate network node can forward directly towards UE2 the data packets without requiring the data packets to be carried over a longer route via a terminating network node. Thus, the intermediate network node receives at S7 another data packet from UE1 , where the data packet is addressed to UE1 , and at S8 forwards the data packet received at S7 directly to UE2.

Thus, the 5-tuple stored in the storage unit of the intermediate network node is used as a link between two logical connections that should be connected together in order to provide a short-cut for data packets transferred from UE1 to UE2. The 5-tuple of data packets generally remains the same regardless of the link direction (uplink or downlink), and thus intermediate network nodes are able to detect receipt of the same previously received data packets. In the case of knowing the identifier of a logical connection (e.g. the TEID value contained in the GTP header of all data packets processed by an intermediate network node) and the link between two logical connections by detecting a matching 5-tuple Next, an intermediate network node knows about two logical connections to be connected in order to provide a shortcut.

As mentioned above, the intermediate network node may be the serving SAE GW node 214 illustrated in Figure 2, or any other network node between the endpoints of the logical connection. In case the intermediate network node is a base station providing a shortcut between the logical connections of two user terminals served by the base station, the base station may connect the radio bearers of the two logical connections. Instead of using the TEID value as an identifier of a logical connection, the base station may use a radio bearer identifier (RBID) or a corresponding identifier to identify and connect the logical connection. In addition, data packets received from the direction of the user terminal are generally not encapsulated, since the connection between the user terminal and the base station is not a tunneled connection. However, the base station may encapsulate data packets for transmission towards the network if the base station is the origin of the tunneled connection. In such a case, the base station maps radio bearers to appropriate tunnels when sending data packets from the user terminal towards the network and tunnels to appropriate radio bearers when sending data packets from the network towards the user terminal.

As an alternative to short-cut provisioning initiated by intermediate network nodes of a logical connection, a termination node of a logical connection may initiate provisioning of a short-cut. The terminating network node may be configured to check the network nodes shared by the first and second logical connections and, if a shared intermediate network node has been detected, instruct the intermediate network node to arrange a shortcut between the first and second connections. In more detail, the terminating network node terminating the first and the second logical connection may receive a data packet via the first logical connection and detect that the data packet does not include a message from the intermediary indicating a provisional shortcut. The terminating network node may then check the intermediate network node shared by the first and the second logical connection. This information can be obtained, for example, from the logical connection's routing table or in another way. Upon detection of such an intermediate network node carrying data packets of the first and second logical connections, the terminating network node may send a message to the intermediate network node instructing the intermediate network node to communicate between the first logical connection and the second logical connection create shortcuts. Additionally, the terminating network node may include identifiers of the first and second logical connections. These identifiers may be the TEID values of the tunneled connections or any other identifiers associated with these logical connections.

In some cases, it may be necessary to avoid simplification for some or all user terminals. The reason could eg be any function in the PDN SAE GW related to user plane traffic, such as Lawful Interception or Charging. Another example is the situation where the user terminal roams in a network of a different operator than the user terminal's home operator. In such cases, shortcut forwarding may be disabled when the user terminal resides on the visited network. In the case of disabling short-cut forwarding temporarily or for some specific user terminals, the intermediate network node can obtain information about the disabling via control signaling information or through a management interface. This information may include identifiers of user terminals for which shortcut forwarding should be disabled and/or instructions to disable shortcut forwarding entirely.

FIG. 7 is a block diagram of an apparatus 700 for providing a shortcut between two logical connections according to an embodiment of the present invention. Both logical connections may include at least one tunneled connection. The device may be an intermediate network node operating in the manner described above. The intermediate network node may be a network node of the telecommunications network illustrated in Fig. 1 or Fig. 2 . The device 700 may include: a first interface 702 for providing a communication link towards a user terminal transmitting data through the device via one or more logical connections; a second interface 706 for providing a communication link towards other (multiple) ends of the logical connection another communication link; and a processing unit 704 that controls the operation of the device 700 . The processing unit 704 may be configured, for example, by software or an ASIC (Application Specific Integrated Circuit) implementation. The device 700 may also comprise a storage unit 708 which stores transmission parameters and transmission configurations related to data transmission in the telecommunications network.

Next, a process according to an embodiment of the present invention for transmitting data packets in telecommunication providing user terminals with one or more dedicated base stations connected to a telecommunication network will be described with reference to the flowchart illustrated in FIG. 8 . wireless communication service. This process may be implemented as a computer process for configuring the processing unit 704 shown in FIG. 7 . Therefore, the process can be run in the above-mentioned intermediate network nodes. The process begins at block 800 .

At block 802, the IP address of the user terminal transmitting the data packet via the intermediate network node is stored in a service list in the intermediate network node. The IP address of the served user terminal can be stored in normal context data related to the logical connection (SAE bearer). Where there is a separate IP address for each logical connection and a given user terminal has established multiple logical connections, the intermediate network node may store the IP address for each logical connection. The intermediate network node can obtain the IP address of the logical connection through standard control signaling during the establishment of the logical connection and/or the handover procedure. If the IP address is not included in the control plane signaling used to set up the logical connection, the intermediate network node may obtain the IP address from any data packets transmitted over the logical connection. The IP address may be obtained by performing an IP lookup on the data packet, ie by reading the source IP address or the destination IP address from the data packet depending on whether the user terminal is sending or receiving the data packet. In case the intermediate network node has received a data packet from the user terminal, the source IP address is read and stored. On the other hand, if the data packet is transmitted in the direction of the user terminal (ie downlink), the destination IP address of the data packet is read. In case of encapsulating a data packet, the intermediate network node may be configured to read the source/destination address from the payload portion of the encapsulated data packet. Now, the intermediate network node has stored the IP address of each logical connection of the served user terminal and linked each stored IP address to a given logical connection.

At block 804, the intermediate network node receives data packets from the first user terminal via the first logical connection. At block 806, compare the final destination IP address of the received data packet with the IP address stored in the service list, and at block 808, check the final destination address of the received data packet with the IP address in the service list Whether there is a match between, that is, whether the destination address is equal to the IP address contained in the service list. If the destination address does not match any IP address stored in the service list, the process moves to block 810, where the data packet is sent to the next network node in the chain towards the destination address, i.e. processed and Send data packets.

On the other hand, if the destination address matches the IP address of the second user terminal whose IP address is stored in the service list, then at block 812, the intermediate network node initiates a connection prepared between the first user terminal and the second user terminal shortcut in . In connection with the preparation of the shortcut, the intermediate network node stores at block 814 at least part of the header information of the data packet. In more detail, a 5-tuple of source IP address, destination IP address, protocol identifier, source port, and destination port may be stored in a storage unit of the intermediate network node. A 5-tuple can be obtained from the raw (encapsulated) data packet illustrated in Figure 6A. As shown above, the source and destination port addresses can be obtained from the UDP header field, the protocol identifier from the Ipv4 header field, and the source and destination IP addresses from the corresponding address fields. The stored 5-tuple may be linked to the identifier of the first logical connection. This identifier may eg be a TEID value. Then, at block 816, the data packet is sent to the terminating network node over the first logical connection.

At block 818, the data packet is received in the intermediate network node from the direction of the terminating network node via the second logical connection. At block 820 , the header information of the data packet received at block 818 is compared with the header information stored at block 814 . In more detail, the stored 5-tuple may be compared with the corresponding 5-tuple of the received data packet. At block 822, it is determined whether the header information matches the stored header information, ie whether the data packet is indeed the same data packet previously received at block 804 over the first logical connection. If it is determined that the header information of the data packet received at block 818 does not match any stored header information, then the process moves to block 824, where it is simply sent towards the destination address specified in the data packet Received data packets.

On the other hand, if it is determined at block 822 that the header information of the data packet received at block 818 matches the header information stored at block 814, then the process moves to block 826, where the intermediate network node connects the first logical connection Connected with a second logical connection to provide a shortcut between the first and second user terminals. In more detail, the intermediate network node links the identifier of the first logical connection to the identifier of the second logical connection. Additionally, the data packet received at block 818 is sent to the second user terminal via the second logical connection.

After the shortcut connection has been arranged, the intermediate network node forwards at block 828 data packets received from the first user terminal via the first logical connection and addressed to the second user terminal directly towards the second user terminal via the second logical connection. In other words, when the intermediate network node receives a data packet from the first user terminal addressed to the second user terminal via the first logical connection, the intermediate network node detects the link between the first and second logical connection, and The data packets are therefore not relayed towards the terminating network node but towards the second subscriber terminal via the second logical connection. If no shortcuts are arranged for the logical connection in question, data packets received via other logical connections (even from the first user terminal) may be relayed towards the terminating network node.

The steps and related functions described above in FIG. 8 are described in no absolute chronological order, and some steps may be performed simultaneously or in an order different from that given. Other functions may also be performed between or within the steps, and other signaling messages may be sent between the disclosed messages. Some steps or parts of steps may also be replaced by corresponding steps or parts of the steps. Operations related to intermediate network nodes illustrate processes that may be implemented in one or more physical or logical entities.

The method described in Fig. 8 can also be implemented in the form of a computer process defined by a computer program. The computer program may be in the form of source code, object code or some intermediate form, and the computer program may be stored in some kind of carrier, which may be any entity or device capable of carrying the program. Such carriers include, for example, recording media, computer memory, read-only memory, electrical carrier signals, telecommunication signals and software distribution packages. Depending on the processing power required, the computer program can be run in a single electronic digital processing unit or it can be distributed among several processing units.

The invention is applicable to the telecommunications network defined above, but also to other suitable telecommunications systems. The protocols used, the specifications of mobile telecommunication systems and networks, their network elements and user terminals develop rapidly. Such developments may require additional changes to the embodiments. Therefore, all words and expressions should be interpreted broadly and are intended to illustrate, not to restrict, the embodiment.

It will be clear to a person skilled in the art that, as technology advances, the inventive concept can be implemented in various ways. The invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.

Claims (28)

1. for the method transporting packet in communication network, comprising:

Each the first logic being associated with the first mobile subscriber terminal in communication network be connected and The go-between joint that one or more second logics being associated with the second mobile subscriber terminal are connected Point receives and connects that transmit by described first logic and come from described first mobile subscriber eventually The packet of end；

The destination-address of the packet received is compared with service list, described clothes Business list includes the ground being transported the mobile subscriber terminal of packet by described intermediate network node Location, wherein each address in the address of mobile subscriber terminal is connected with one or more logics Being associated, the connection of the one or more logic is based upon mobile subscriber terminal and communication network Core network in terminating network node between；

In described packet, shortcut preparation designator, institute is inserted by described intermediate network node State shortcut preparation designator and show that described intermediate network node is just for institute to described terminating network node State the first logic and connect preparation shortcut；

Receive confirmation to described shortcut preparation designator from described terminating network node, described really Recognize and include shortcut preparation approval message or shortcut preparation refuse information；And

If it is included described in the destination-address of described packet and described service list The address coupling of the second mobile subscriber terminal, then connect towards described through specific second logic Second mobile subscriber terminal transports the packet received, wherein said specific second logic Connect and first pass through following manner and determine: be carried through described the to described terminating network node The packet that one logic connects and receives；Connect through the one or more second logic In one from described terminating network node receive described packet；And patrol described first Collect to connect to be connected with described specific second logic and be attached, in order to provide shortcut, for warp Connected to transport to described specific second logic by described shortcut and ensuing patrol by described first Collect the packet connected and receive.

Method the most according to claim 1, also includes: if in described service list Including described destination-address, then the terminating network node fortune connected towards described first logic The packet received described in sending.

The most according to claim 1 or claim 2, wherein, described second mobile subscriber The second logic that terminal has by described intermediate network node connects, wherein said first logic Connecting and described second logic connection includes that at least one tunnel type connects, described method also includes:

By described first logic is connected to described second in described intermediate network node Logic connects to come between described first mobile subscriber terminal and described second mobile subscriber terminal Data transmit arranges shortcut.

The most according to claim 1 or claim 2, described first logic is connected and institute State the second logic connection to be attached also including: by described first in described intermediate network node The identifier that logic connects is linked to the identifier that described second logic connects.

The most according to claim 1 or claim 2, also include:

The header information of the packet received described in storage at least part of；

Connected by described first logic and divide towards the described data of described terminating network node transport Group；

Connected by described second logic and receive described packet from described terminating network node；

By the header information of described packet that receives from described terminating network node with described Header information stored at least partly compare；

If from the described header information of the described packet that described terminating network node receives With described header information stored at least partly mate, then in described intermediate network node Connect to be connected with described second logic by described first logic and be attached；And

Will be at described first mobile subscriber terminal and described second in described intermediate network node The packet received addressed transmitted between mobile subscriber terminal is directly toward every number Header information according to packet is addressed as described in the described movement of destination of packet User terminal transports.

Method the most according to claim 5, the head of the packet received described in storage At least partly including of portion's information: store following header information: the source address of described packet, The destination-address of described packet, the protocol identifier of described packet, source port ground Location and destination's port address.

The most according to claim 1 or claim 2, also include: by described mid-level net Network node provides one or more Internet protocols to connect as one or more mobile subscribers Logic between terminal with described terminating network node is connected.

The most according to claim 1 or claim 2, wherein, described intermediate network node Being private base station, described method also includes:

Described first mobile subscriber terminal serviced to described private base station by described private base station With the first nothing that described second mobile subscriber terminal provides the part connected as described first logic The carrying of line electricity and the second radio bearer of the part as described second logic connection, Qi Zhongsuo State the first logic connection to be associated with described first mobile subscriber terminal, and described second logic is even Connect and be associated with described second mobile subscriber terminal；

Described data are received from described first mobile subscriber terminal by described first radio bearer Packet；

The destination-address of described packet is compared with described service list；And

If it is included described in the destination-address of described packet and described service list The address coupling of the second mobile subscriber terminal, then by described second radio bearer towards described The packet received described in second mobile subscriber terminal transport.

Method the most according to claim 3, also includes:

At the described intermediate network node being positioned at the tunnel type connection that described first logic connects In, will transmit and the purpose of packed described packet to be connected by described tunnel type Address included in way address and described service list compares.

Method the most according to claim 9, also includes: hold for described packet Row address search procedure, to obtain the mesh in the payload part being encapsulated into the packet encapsulated Way address.

11. methods according to claim 3, also include: identify to be connected described One logic connects and described second logic connects, in order to connect and described according to described first logic The tunnelling end identifier that second logic connects provides shortcut.

12. according to claim 1 or claim 2, also includes: configures selectively Described intermediate network node, moves with described second with disabling for described first mobile subscriber terminal Data between user terminal transmit the function arranging shortcut.

13. methods according to claim 3, wherein, at the joint that described tunnel type connects Point realizes described method.

14. 1 kinds of equipment being used for transporting packet in communication network, comprising:

Interface, for transmitting and receiving the packet as signal of communication；And

Each the first logic being associated with the first mobile subscriber terminal in communication network be connected and The go-between joint that one or more second logics being associated with the second mobile subscriber terminal are connected The processing unit of point, wherein said processing unit is configured to: receive by described first logic Connect packet that is that transmit and that come from described first mobile subscriber terminal；By described data The destination-address of packet compares with service list, and described service list includes by described Intermediate network node transports the address of the mobile subscriber terminal of packet, and wherein mobile subscriber is eventually Each address in the address of end is connected with one or more logics and is associated, one or many Individual logic connects the termination net in the core network being based upon mobile subscriber terminal and communication network Between network node；Wherein said processing unit is further configured to: to will be towards described terminating network Inserting shortcut preparation designator in the described packet that node transports, described shortcut preparation indicates Accord with and show that described intermediate network node just connects for described first logic to described terminating network node Preparation shortcut；And receive to described shortcut preparation designator really from described terminating network node Recognizing, described confirmation includes shortcut preparation approval message or shortcut preparation refuse information；And its Described in processing unit be further configured to: if the destination-address of described packet is with described The address coupling of described second mobile subscriber terminal that service list includes, then by specific Second logic connects transports, towards described second mobile subscriber terminal, the packet received, its Described in specific second logic connect and first pass through following manner and determine: to described termination net The packet that network node is carried through described first logic connection and receives；Through described one One during individual or multiple second logics connect is divided from the described data of described terminating network node reception Group；And connect to be connected with described specific second logic by described first logic and be attached, So that offer shortcut, connect for connecting transport via described shortcut to described specific second logic The packet received by described first logic connection got off.

15. equipment according to claim 14, wherein, described processing unit is also configured Become: if not including destination-address at described service list, then by described interface towards The packet received described in the terminating network node transport that described first logic connects.

16. according to the equipment described in claim 14 or 15, and wherein, described second moves User terminal is had the second logic set up by described intermediate network node and connects, wherein said First logic connects and described second logic connection includes that at least one tunnel type connects, and institute State processing unit to be further configured to by described first logic being connected in described intermediate network node Receive described second logic in succession to connect to come for described first mobile subscriber terminal and described second shifting Data between dynamic user terminal transmit arranges shortcut.

17. according to the equipment described in claim 14 or 15, wherein, described processing unit It is further configured to the identifier by described first logic being connected in described intermediate network node Described first logic is connected and described second by the identifier being linked to described second logic connection Logic connection is attached.

18. according to the equipment described in claim 14 or 15, wherein, described processing unit It is further configured to: the header information of the packet received described in storage at least part of；Logical Cross described first logic to connect towards the described packet of transport of described terminating network node；Pass through Described second logic connects from the described packet of reception of described terminating network node；Will be from described The header information of the described packet that terminating network node receives and the institute of described header information At least partly comparing of storage；If the described number received from described terminating network node According to packet header information and described header information stored at least part of mate, then in institute State described first logic is connected to be connected with described second logic by intermediate network node and carry out even Connect；And by by described interface to and address into described first mobile subscriber eventually The packet transmitted between end and described second mobile subscriber terminal is directly toward each data and divides The described mobile subscriber terminal of the destination as packet addressed in the header information of group Transport.

19. equipment according to claim 18, wherein, described processing unit is also configured Become to store the following header information at least portion as the header information of the described packet received Point: the source address of described packet, the destination-address of described packet, described data Protocol identifier, source port address and destination's port address of packet.

20. according to the equipment described in claim 14 or 15, wherein, at one or more It is at least part of that described logic between many mobile subscriber terminals with described terminating network node is connected It is that the Internet protocol arranged by described intermediate network node is connected.

21. according to the equipment described in claim 14 or 15, wherein, described go-between Node is private base station, and described processing unit is further configured to: to by described private base station Described first mobile subscriber terminal and described second mobile subscriber terminal that are serviced provide as institute State the first radio bearer of the part that the first logic connects and as described second logic connection Second radio bearer of part, wherein said first logic connects and described first mobile subscriber Terminal is associated, and described second logic connection is associated with described second mobile subscriber terminal, To be divided from the described first described data of mobile subscriber terminal reception by described first radio bearer Group, compares the destination-address of described packet with described service list, and such as What the destination-address of the most described packet and described service list included described second moves The address coupling of user terminal, then be connected to described second wireless by described first radio bearer Electricity carrying, to carry between described first mobile subscriber terminal and described second mobile subscriber terminal For shortcut.

22. equipment according to claim 16, wherein, described intermediate network node is positioned at In described tunnel type connects, and wherein said processing unit is further configured in order to pass through State tunnel type connection to transmit and the destination-address of packed described packet and described service Address included in list compares.

23. equipment according to claim 20, wherein, described processing unit is also configured Become and perform address search process for described packet, be encapsulated into, to obtain, the data encapsulated Destination-address in the payload part of packet.

24. equipment according to claim 16, wherein, described processing unit is also configured Described first logic becoming mark to be connected connects and described second logic connects, in order to according to institute State the tunnelling end identifier that the first logic connects and described second logic connects and shortcut is provided.

25. according to the equipment described in claim 14 or 15, wherein, described processing unit It is further configured to configure described intermediate network node selectively, moves for described first with disabling Data between user terminal and described second mobile subscriber terminal transmit the function arranging shortcut.

26. equipment according to claim 16, wherein, described intermediate network node is institute State the node that tunnel type connects.

27. 1 kinds of apparatus for network node, it includes according to any aforementioned claim 14 to 24 Described equipment.

28. 1 kinds of equipment being used for transporting packet in communication network, comprising:

It is connected for the first logic being associated with the first mobile subscriber terminal in communication network And the go-between that one or more second logics being associated with the second mobile subscriber terminal are connected Node receives and connects that transmit by described first logic and come from described first mobile subscriber The device of the packet of terminal；

For the device that the destination-address of described packet and service list are compared, Described service list includes transporting the mobile subscriber of packet eventually by described intermediate network node The address of end, the wherein each address in the address of mobile subscriber terminal and one or more logics Connection is associated, and the connection of the one or more logic is based upon mobile subscriber terminal and telecommunications Between terminating network node in server network；

For being inserted shortcut preparation designator in described packet by described intermediate network node Device, described shortcut preparation designator shows described go-between to described terminating network node Node is being just that described first logic connects preparation shortcut；

For receiving the dress of the confirmation to described shortcut preparation designator from described terminating network node Putting, described confirmation includes shortcut preparation approval message or shortcut preparation refuse information；And

If included by the destination-address and described service list of described packet The address coupling of described second mobile subscriber terminal then connects towards institute through specific second logic State the second mobile subscriber terminal and transport the device of packet received, wherein said specifically Second logic connection first passes through following manner and determines: transport logical to described terminating network node The packet crossing described first logic connection and receive；Through the one or more second One during logic connects receives described packet from described terminating network node；And by institute State the first logic to connect to be connected with described specific second logic and be attached, in order to offer shortcut, Ensuing by described for connecting transport via described shortcut to described specific second logic The packet that first logic connects and receives.