Combining ip and cellular mobility

[0001] The invention relates to a network control node, a terminal and a method for controlling various types of connection sessions.

Description of the Related Art [0002] The invention relates to multi-accessibility and mobility. 3GPP is currently discussing various ways to implement MA mobility (mobile access).

[0003] Currently, there are many problems with the use of many mobility solutions:

- Each mobile solution has its own gateway. The traffic should usually go through many gates (for example, GGSN and HA).

- Each mobile solution uses a certain type of tunneling. Having many tunnels is not optimal, especially in the case of cellular access.

- Each mobile solution has its own gate selection mechanism. In principle, it is difficult to choose the same goal.

[0004] In addition, Mobile IPv4 requires a method for configuring clients.

[0005] Therefore, the support of connection sessions in the network should be improved. Appropriate prior art documents are EP 1 435 748 A1, EP 1 531 645 A1, US 2004/246933 A1 and US 2004/166843 Al.

Summary of the invention [0006] The object of the invention is to solve the above-mentioned problem and to ensure mobility and continuity of a session even when the gateway has different mobile solutions. The invention is defined by a gate control method according to claim 11, a method for controlling a terminal according to claim 17, a gate device according to claim 1, a terminal device according to claim 7 and a system according to claim 21.

[0007] According to several embodiments of the invention, the object is achieved by a gate comprising a support unit configured to support a plurality of connection session types; a delivery unit configured to provide a session for connecting to the terminal; and a coupled unit configured to couple the parameter to the terminal connection session.

[0008] Alternatively, according to several embodiments of the invention, this object is achieved by a terminal including a support unit configured to support a plurality of connection session types; a delivery unit configured to provide a gateway session; and a receiver configured to receive a parameter that is coupled to the gate.

[0009] As another alternative, according to several embodiments of the invention, the object is achieved by a gateway control method in a network, the gateway may support multiple types of connection sessions, the method comprising: providing a session of connection to a terminal; and coupling the parameter with the terminal connection session.

[0010] Furthermore, according to several embodiments of the invention, the object is achieved by a method of controlling a terminal, wherein the terminal is capable of supporting a plurality of types of connection sessions; the method includes: providing a connection session with the gateway; and receiving the parameter that is coupled to the gate.

[0011] According to embodiments of the invention, there is provided a system that allows mobility for a terminal via at least two different mobility protocols in which:

- the mobile gateway and terminal share a common mobility session,

- the said joint mobility session may be updated by any of the mobility protocols mentioned, and

- each mobility protocol provides information to the terminal related to all other mobility protocols during registration.

[0012] Thus, even if the terminal changes the type of connection to the network control element (e.g. from a WLAN to GPRS), the connection session as such can be clearly identified. Hence, the mobility and continuity of the session can be obtained even for different mobility solutions (different types of connections).

[0013] This means that the invention provides a mobility solution that combines multiple mobility technologies and enables session continuity in these multiple mobility technologies.

Brief Description of the Drawings [0014] The invention is described by reference to the accompanying drawings, in which:

Fig. 1 shows a signal flow in which the terminal using the integrated mobility session first turns on using the GPRS connection session according to the first embodiment, Fig. 2A shows a signal flow in which the terminal first turns on using a connection session using the integrated mobility session mobile IP according to the first embodiment, FIG. 2B shows a layer structure in the terminal and gate; FIG. 3 shows the signal flow in which the terminal using the integrated mobility session first turns on using the GPRS connection session according to the second embodiment; FIG. a signal flow in which the terminal using the integrated mobility session is first switched on using the IP mobile connection session according to the second embodiment, FIG.5 shows a signal flow in which the terminal using the integrated mobility session first turns on using a GPRS connection session according to the third embodiment, FIG. 6 shows a signal flow in which the terminal first turns on using an integrated mobile session according to a third embodiment, FIG. 7A shows the basic configuration of the gate according to the embodiments, and FIG. 7B shows the basic configuration of the terminal according to the embodiments.using the IP mobile connection session according to the third embodiment, Fig. 7A shows the basic gate configuration according to the embodiments, and Fig. 7B shows the basic terminal configuration according to the embodiments.using the IP mobile connection session according to the third embodiment, Fig. 7A shows the basic gate configuration according to the embodiments, and Fig. 7B shows the basic terminal configuration according to the embodiments.

Detailed description of preferred embodiments [0015] In the following preferred embodiments of the invention are described with reference to the accompanying drawings.

In general, preferred embodiments propose an integrated mobility solution in which one gateway (also referred to as a mobility gate or an integrated mobility gate) supports a single mobility session using several mobility technologies and can return to the mobile node configuration parameters (MN). node) or session parameter to ensure that the mobile node stays connected to the same gateway if mobility technology is used. In particular, the gateway assigns the same home address to the mobile node when the mobility technology changes during the session so that the mobility technology change is invisible to the corresponding node.

[0017] Furthermore, the terminal (i.e. mobile node (MN)) has a single mobility session and is intended to update this mobility session via various protocols (3GPP mechanism, mobile IP, Mobike) depending on the access used. In addition, after accessing via one protocol, the mobile node will receive configuration / session parameters and use it to configure the remaining protocols within this mobility session.

The following is a more detailed example according to the first embodiment, referring to the signal flow shown in Fig. 1.

[0019] In this example, it is assumed that the intelligent service node (ISN) (connecting the home agent GGSN-MIPv4) is the gate mentioned above, and the mobile station first connects via GPRS.

[0020] The flow of signals is described below. It starts when the power supply is switched on in GPRS, in which a GGSN and HA collocation is provided. [0021] In step A1, the UE (user entity) or mobile station (MS) or mobile node (MN) is sends a PDP context request (packet data protocol). Preferably, the mobile station adds an indication that integrated mobility of MIPv4 is supported. This is preferably added in the protocol configuration option, so that SGSN transfers it in a transparent manner. In Figure 1, the indication includes the ID of the mobility session. For example, a certain value of 0000 indicates that there is no previous mobility session. + [0022] Next, an integrated mobility session is created at the ISN node (step A2). An integrated mobility session can be updated via GPRS or MIP, as illustrated below. If the GPRS session is turned off, the integrated mobility session will not be terminated. But it will wait for a possible update of the mobile IP.

[0023] In step A3, the smart service node returns the contextual accept PDP, including its IP address MIPv4 HA (home agent) (and / or optionally the logical name of the HA NAI home network access identifier, e.g. defined in RFC3846). ), a temporary joint secret (valid for this session), SPI (Security Parameter Index) and, optionally, a GGSN identity (preferably designated as APN (access point name)). Optionally, specify the unique identifier of the mobility session. This is preferably added in the protocol configuration option, so that SGSN transfers it in a transparent manner. It should be noted that the IP address returned to the MS station in response to the PDP context activation will be the mobile node's address for the duration of the mobility session.

[0024] This means that as long as the mobile station remains in the GPRS network, it considers it to be its own home network (from the point of view of mobile IP) and does not use mobile IP. The ISN node and the MS station have a mobility session containing GPRS parameters and a temporary joint secret (valid for this session), SPI (security parameter index). There is no active MIP session, but the MS station has configured its mobile IP stack using the parameters obtained from the PDP context activation procedure (HA address, home address, common secret, SPI).

[0025] At step A4, it is now assumed that the MN detects a WLAN that has a higher priority than the cellular network, e.g. it is a home WLAN.

[0026] In step A5, he sends a registration registration MIP (RRQ) request to the address HA received in step A3. The authentication field is calculated using the temporary joint secret and the SPI obtained in step A3. The RRQ request also includes the home address assigned in step A3 by GGSN. Preferably, the request also comprises HA NAI (according to RFC 3846) and a mobility session ID as the supplier extension.

[0027] In step A6, the ISN receives the request and finds the appropriate session context using the session ID (remember that address support is assumed, so the home address is not enough to uniquely identify the mobile station). The ISN node authenticates the mobile station and accepts the request. This means that in step A6 the mobility session is identified using the mobility session ID, the security procedures are performed to verify the correctness of the request, and the update is performed in the ISN to guide the session through this new access.

[0028] In step A7, a corresponding response (R Resp) is sent to the MS station. Optionally, the same mobility session ID should be included (to simplify the protocol) in the accepting message as well as the GGSN identity marked as APN. The MIP session is determined. For example, an IP-in-IP tunnel is created, and all traffic is now routed to the MS station address.

[0029] The ISN node and the MS station have a mobility session (determined by a unique mobility session ID), including GTP (GPRS tunneling protocol) parameters and MIP parameters. Both sessions are active.

[0030] Then, the SGSN may release the PDP context based on the clock (there is no data traffic in the SGSN). In step A8, the PDP context is deactivated. The ISN node removes parameters related to the GTP tunnel.

[0031] The ISN node and the MS station have a mobility session (determined by a unique mobility session ID) including MIP parameters. The MS station also contains the GGSN identity marked as APN. GTP session is not active.

[0032] In step A9, it is assumed that the MS station returns to the cell range. Because he has an active mobility session, he will not use the default APN, but will use the address obtained in step A3 or A7 (GGSN ID). The standard SGSN will send the request to the same ISN (because only one is coupled to this APN). The mobile station adds the mobility session ID. This is preferably added in the protocol configuration option, so that SGSN transfers it in a transparent manner.

At step A10, the smart service node returns the context accept PDP, including the IP address MIPv4 HA (and optionally the logical name HA NAI, as in RFC3846), temporary common secret (valid for this session), SPI (security parameter index) and identity. GGSN (preferably designated as APN). Alternatively, include the same mobility session identifier (to simplify the protocol). This is preferably added in the protocol configuration option, so that SGSN transfers it in a transparent manner.

[0034] In the following, another example according to the first embodiment is described, referring to the signal flow shown in Fig. 2A. In this example, an ISN intelligent service node (connecting the GGSN-MIPv4 home agent) is assumed and it is assumed that the MS station first connects via mobile IP (MIP).

[0035] The following is a signal flow that especially shows power on in the WLAN, followed by a move in the direction of GPRS, in which the GGSN and HA collocations are provided.

[0036] In step B1, the MN is connected via, for example, a WLAN network, sending a MIP registration request to a pre-configured HA address. The authentication field is calculated using the pre-configured joint secret and SPI. The RRQ request also includes NAI MN to request dynamic allocation of the home address. Preferably, the request also includes a mobility session ID set to 0000 as the provider extension.

[0037] In step B2, the ISN receives the request, authenticates the MN and detects that it is a new session (because the session ID is 000 in step B1), dynamically allocates the home address as well as the unique session identifier. An ISN returns GGSN identification identified as APN in the accept message. The MIP session is determined. For example, an IP-in-IP tunnel is created, and all traffic is now routed to the MS station address.

[0038] In step B3, the MN updates the GPRS configuration with the received APN for the duration of this mobility session. This is also illustrated in Fig. 2B, which illustrates the corresponding layer structure. MIP, IP and WLAN are shown in bold to emphasize settings.

[0039] The structure of the layers is the same for the terminal and for the gate.

[0040] Furthermore, the terminal may be a single device (e.g. a cell phone) or comprise a plurality of different devices.

[0041] For example, a common mobility layer may be on a laptop while the GPRS layer may be on a data card.

[0042] As regards the structure of the layers, it was noted that there is a common layer of mobility at the top.

[0043] At the terminal, this common mobility layer provides:

- virtual interface to the application.

- single home address shared between MIP and GPRS

- the ability to change between GPRS and MIP without affecting the application

- at the beginning of the session or during the update, the common mobility layer will configure one stack (e.g. GPRS) with the received information (GPRS APN, common session ID) by another stack (e.g., MIP) [0044] The layered structure of the gateway is described below the same as shown in Figure 2B.

[0045] Typically, the gateway integrates many mobility technologies.

[0046] A common layer of mobility at the gate:

- controls the registration procedure.

- generates information to be sent during the MS registration procedure (for example, home address ...)

- generates a unique session ID

- maintains the session when the mobility protocol is changed

- hides the change between GPRS and MIP in any external correspondent nodes

- at the beginning of the session, or during the update, the common mobility layer will provide one stack (e.g. GPRS) with the information sent to the terminal (MIP HA address, security parameters; HA name; Common session ID) associated with another stack (e.g. MIP) ) [0047] In step B4, it is now assumed that the mobile node loses its connection to the WLAN so that it now moves to GPRS.

[0048] Thus, in step B5, the MN sends a PDP creation request, including the mobility session ID obtained in step B2 and using the APN protocol obtained in step B2. Normally SGSN selects GGSN (for example, with a DNS server (domain name server). The network is configured such that the APN uniquely identifies the ISN selected in step B1, the mobility session ID is added in the protocol configuration option, whereby the SGSN transmission moves it in a transparent manner.

[0049] In step B6, the ISN returns the contextual accept PDP, including the IP address MIPv4 HA (and optionally the logical name HA NAI, as in RFC3846), the temporary common secret, the SPI (security parameter index). Alternatively, include the same mobility session identifier (to simplify the protocol). This is preferably added in the protocol configuration option, so that SGSN transfers it in a transparent manner.

[0050] Step B7 and B8 in the figure show what happens when the MS station returns to the MIP connection.

[0051] In particular, in step B7, the MN sends a MQ RRQ to ISN containing the session ID of the mobility session (this may be, for example, in this case 1111). In step B8, the ISN sends R Resp to the MN, containing the ISN defining the provider (namely APN = "GGSN / HA7"), the home agent address (HoA) and the mobility session ID.

[0052] The implementation of the MN node is described below. A preferred way to implement an MS station is to have a combined mobility layer between the application and the GPRS stack / MIP stack. The application will use the virtual interface to connect to this connected mobility layer and will receive its home address via this interface. The combined mobility layer stores in the context of the information related to the mobility session, it will follow the active interface (MIP or GPRS) and will configure the MIP and GPRS protocol with the appropriate parameters for the active mobility session. After completing the mobility session, the combined mobility layer can remove the parameters associated with the mobility session. The GPRS and MIP stack will then use the pre-configured parameters the next time you connect.

[0053] According to a first embodiment, the mobility session ID is used as a parameter identifying a connection session (e.g., a mobility session). Namely, it was assumed that one MN node can have many simultaneous sessions. The mobility session ID is a robust way to uniquely identify the right session. The IP address can not be used to uniquely identify the session because the private address may overlap.

[0054] The MN node identifier could be used to uniquely identify the session but would limit the number of sessions to one per MN node. This is not practical because different mobility protocols usually use a different type of identity. This would not support a concept such as a UMTS router (having many computers connected to one modem

UMTS) [0055] As mentioned above, this mobility session ID may be used (also referred to in short as session ID only), which supports integrated mobility. This can be indicated in step A1 using the session ID containing only 000000.

[0056] Security considerations: the proposed mechanism is reasonably secure because the temporary joint secret is returned by GPRS which is encrypted by radio. To ensure a higher level of security, the common secret can be returned in an encrypted form. There are many other ways to increase security, but this is not the main topic here.

[0057] Backward compatibility: an old GGSN or HA simply ignores the new field. The mobile station should be able to work with them and have separate GPRS and MIP sessions.

[0058] If the first connection is connected to the MIP, the MS must have a pre-configured common secret and MIP HA. The alternative is that the MS station will always connect to GPRS first. Another alternative is that MS and the network store the parameters from the previous session.

[0059] In the following, a second embodiment is described, referring to Figs. 3 and 4.

[0060] According to a first embodiment described above, the GPRS signaling includes MIP parameters and the MIP signaling includes GPRS parameters. This means that, for example, the mobility session ID is included in the context-based PDP acceptance messages (step A3).

[0061] However, according to the second embodiment, the GPRS transmission triggers a MIP message (agent announcement) that contains MIP parameters (including the mobility session ID) instead of sending them within the GPRS transmission.

[0062] Fig. 3 shows a corresponding modification of the signal flow from Fig. 1. Here, steps C1 to C10 are identical to steps A1 to A10, except for steps C3 and C10 and additionally of steps C3bis and C10bis.

[0063] In steps C3 and C10, only context-aware PDP messages are sent without other parameters. Instead, announcement messages of the agent containing these parameters are sent in step C3bis and C10bis.

[0064] Fig. 4 shows a corresponding modification of the signal flow from Fig. 2. Here, steps D1 to D8 are identical to steps B1 to B8, with the exception of step D6 and additionally step D6bis.

[0065] Similarly as in FIG. 3, only context-dependent PDP messages are sent in step D6 without other parameters. Instead, an announcement of an agent containing these parameters is sent in step D6bis.

[0066] In the following, a third embodiment is described in which the parameter for identification [0067] According to this embodiment, HA NAI is used to identify the ISN.

This is illustrated in Figures 5 and 6.

[0068] The use of HA NAI is particularly advantageous if the HA cluster is on one IP address. Namely, HA NAI uniquely identifies one of HA. In the case of Flexi ISN it can uniquely identify the appropriate service card. It should be noted that the protocol can be designed so that HA NAI = GGSN APN, providing a unique identity for ISN.

[0069] In a preferred embodiment according to an exemplary embodiment, a single logical name is coupled to an ISN. This name can be used either as HA NAI (RFC3846) or as GPRS APN (access point name). The advantage is that you can use standard MIP signaling (there is no new provider extension to send back the APN and only HA NAI is sent). The client will use the returned logical name as APN for GPRS transmission.

This is illustrated in FIGS. 5 and 6, in which the steps E1 to E10 and F1 to F8 are identical to steps A1 to A10 and B1 to B8 from figures 1 and 2, except for steps

E7, E9, F2, F5 and F8.

[0071] In FIG. 5, in step E7, HA NAI is sent in the R Resp alert instead of the GGSN identity. This is used in the PDP context request in step E9.

[0072] In Fig. 6, in steps F2, F5 and F8, R Resp contains HA NAI instead of the supplier extension as in steps B2, B5 and B8 in Fig. 2.

[0073] Thus, using the embodiments described above, a connection session can always be reliably identified. The implementation does not cause the GPRS overhead, provides a simplified configuration, and the traffic passes through one gate instead of two. In addition, 3GPP operators now have the option of maintaining control over the subscriber.

[0074] Fig. 7A illustrates a basic gate configuration according to an exemplary embodiment. In particular, the gateway 1 may comprise a support unit 11 configured to support a plurality of connection session types; a delivery unit 12 configured to provide a session for connecting to the terminal; and a coupled unit 13 configured to couple the parameter to the terminal connection session.

[0075] Fig. 7B shows the basic configuration of the gate according to an exemplary embodiment. Terminal 2 may include: a support unit 21 configured to support multiple types of connection sessions, a delivery unit 22 configured to provide a gateway session and a receiver 23 configured to receive a parameter that is coupled to the gateway.

[0076] The invention is not limited to the embodiment described above and various modifications are possible.

[0077] For example, the invention is not limited to the mobility protocols described above, but also applies to other mobility protocols. According to the principles described here, a combined mobility session can support connectivity through more than 2 basic protocols.

[0078] A particularly important example is the combination of 3GPP LTE (long term evolution), GPRS and Mobike mobility. In this case, when the IPsec connection is established via the Mobike service, the extension to MObike will be provided by the MN node with the ISN identifier (alternatively there may be 2 identifiers for LTE and one for GPRS) and a unique identifier of the mobility session. When the MS moves on the 3GPP LTE network, it sends an ISN identifier to connect to the same gateway, and this gateway will uniquely identify the session by the mobility session identifier. Since the same IP address will be assigned to the mobile station, the external answering node will not detect any changes.

[0079] Similarly, the invention also applies to MIPv6. One difference is that in MIPv6 the security parameters are slightly different. Another difference in MIPv6 is that the home IPv6 address is unique, and in some cases, the session ID parameter can be avoided.

[0080] Furthermore, the invention is not only limited to mobile connection sessions. This means that you can also enter permanent access points to the network. For example, a laptop computer can be accessed via a WLAN, but it can also be connected via a network cable.