CN102123493B

CN102123493B - Registration method and device for packet data network connection

Info

Publication number: CN102123493B
Application number: CN201110041642.2A
Authority: CN
Inventors: 吴问付; 胡伟华
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2008-03-26
Filing date: 2008-06-13
Publication date: 2014-11-19
Anticipated expiration: 2028-06-13
Also published as: CN102123493A

Abstract

The invention discloses a processing method for packet data network (PDN) connection, which comprises the following steps of: receiving a PDN connection request initiated by user equipment (UE); and allocating a PDN connection identifier to the PDN connection request, wherein the PDN connection identifier is used for identifying the PDN connection, so that for different PDN connections, the PDN connection identifier can be used for positioning one PDN connection. The invention also provides a device corresponding to the method.

Description

Registration method and device for packet data network connection

The present application is a divisional application of a chinese patent application entitled "registration method and apparatus for packet data network connection" filed in 13/6/2008 in 2008, and having an application number of 200810110181.8, and requests priority of a chinese patent application entitled "registration method and apparatus for packet data network connection" filed in 26/3/2008 in 2008, having an application number of 200810086366. X.

Technical Field

The present invention relates to the field of network technologies, and in particular, to a method and an apparatus for registering Packet Data Network (PDN) connection.

Background

Third Generation partnership Project (3 GPP) networks refer to some networks defined by the 3GPP organization, including 3GPP Long Term Evolution (LTE) networks in addition to conventional General Packet Radio Service (GPRS) networks and Universal Mobile Telecommunications System (UMTS) networks; the non-3GPP Network (non-3GPP) refers to some Access networks defined by non-3GPP organizations, such as Wireless Local Area Network (WLAN), Worldwide Interoperability for Microwave Access (Wimax), Code Division Multiple Access (CDMA), and so on.

To gain an understanding of the 3GPP LTE network, the E-UTRAN network architecture is first described below in conjunction with fig. 1. In fig. 1, the E-UTRAN is used to implement all functions related to the evolved network; a Mobility Management Entity (MME) is mainly responsible for Mobility Management and session Management, including user context and Mobility state Management, allocating a user identity temporary identifier, and the like; a Serving Gateway (SGW) is a User plane entity of a UE (User Equipment) accessing a core network, and terminates an interface of the E-UTRAN; a Packet Data Network Gateway (PGW) is a user plane anchor Network element between a 3GPP Network and a non-3GPP Network, and terminates interfaces with external Packet Data Networks (PDNs); the interface between the SGW and the PGW may use GPRS Tunneling Protocol (GTP) or Proxy Mobile Internet Protocol (PMIP); a Home Subscriber Server (HSS) for storing Subscriber subscription information; a Policy and Charging Rule Function (PCRF) for Policy control decision and flow Charging control Function; an Authentication, Authorization and accounting Server (AAA Server) for performing access Authentication, Authorization and accounting functions for the UE; a Serving GPRS switching support node (SGSN) is used to implement functions such as route forwarding, mobility management, and user information storage in a GPRS network; UMTS Terrestrial Radio Access Network (UTRAN), GSM/EDGE Radio Access Network (GERAN), for implementing all Radio related functions in the existing GPRS/UMTS Network. It should be noted that, currently, 3GPP Long Term Evolution (LTE) is in a research phase, and fig. 1 only shows a possible LTE network schematic diagram.

It is well known in the art that before a UE accesses a particular PDN, a PDN connection (also referred to as a data connection in some protocol documents) needs to be established to this PDN. For example, a data channel is established between the UE and the PGW, and data between the UE and the PDN is transmitted over the data channel.

In order to realize uninterrupted service when the UE switches between the 3GPP network and the non-3GPP network, the target network needs to acquire PDN connection information established by the UE in the source network. When establishing a PDN connection in a source network, the UE sends an Access Point Name (APN) and PGW address information required for the PDN connection to the HSS for storage. The target network acquires the registration information from the HSS, initiates a PDN establishment program according to the registration information, and completes PDN connection establishment between UE and PDN in the target network.

Referring to fig. 2, an Attach (Attach) procedure for accessing a 3GPP network, which involves a registration and establishment procedure of a PDN connection, includes:

s201: the UE sends an Attach Request (Attach Request) message to a mobility management network element;

for GERAN/UTRAN networks the mobility management network element refers to SGSN, and for E-UTRAN networks the mobility management network element refers to MME.

S202: an authentication process is executed among the UE, the mobility management network element and the HSS;

s203: the method comprises the steps that a position updating and signed data inserting process is executed between a mobility management network element and an HSS, the address of the mobility management network element is registered in the HSS, and meanwhile, the HSS inserts signed data of UE into the mobility management network element;

s204: a mobile management network element selects a PGW according to an APN corresponding to UE default, sends a message of creating a default bearer carrying a PGW address to the SGW, and requests to establish default PDN connection;

s205: SGW sends a request message for creating default load or a proxy binding update message to the selected PWG;

if the interface protocol between the SGW and the PGW uses a GTP protocol, a default bearer creation request message is used; if the interface protocol between the SGW and the PGW uses the PMIP protocol, a proxy binding update message is used.

S206: the PGW replies a create default response or a proxy binding acknowledgement message to the SGW, if the PGW allocates the IP address used by the PDN connection, the message carries the IP address used by the PDN connection, and if the PGW does not allocate the IP address used by the PDN connection (for example, the PGW allocates the IP address by a dedicated server or after the attach is completed, the UE allocates the IP address used by the PDN connection by using a Dynamic Host Configuration Protocol (DHCP) mechanism), the message does not carry the IP address used by the PDN connection, and the UE uses the IP address to implement the final PDN connection;

s207: the SGW replies a default bearer establishing response message to the mobility management network element;

s208: the mobility management network element replies an Attach Accept (Attach Accept) message to the UE;

s209: a mobile management network element sends a location updating request message to an HSS, wherein the message carries an APN (access point name) and a PGW (packet data network) address of a default PDN (public data network) connection used by UE (user equipment);

s210: and the HSS stores the APN and the PGW address used by the UE and replies a location update response message to the mobility management network element.

For a PDN connection establishment procedure initiated by the UE, refer to the flow in fig. 3, where S301 is that the UE sends a PDN connection Request (PDN Connectivity Request) message to the mobility management element, and carries an APN of a PDN connection to be established in the message, and correspondingly, S306 is that the mobility management element replies a PDN connection Accept (PDN Connectivity Accept) message to the UE, and the remaining steps of the PDN connection establishment procedure initiated by the UE are similar to those in fig. 2 and are not described herein.

When the UE is accessed in a non-3GPP network (such as a Wimax network) or the UE requests PDN connection in the non-3GPP network, the PGW registers APN and PGW address information used by the PDN connection used by the UE to an AAA Server, and the AAA Server notifies the HSS. And the HSS stores the APN and PGW address information used by the PDN connection used by the UE.

When the UE is switched between a 3GPP network and a non-3GPP network, for example, when the UE is switched from the non-3GPP network to the 3GPP network, a mobility management network element acquires APN and PGW address information used by the UE in the non-3GPP network from an HSS, and for each APN and PGW record, an MME initiates a PDN connection establishment procedure (such as S202 to S205) and establishes a PDN connection established by the UE in the non-3GPP network in the 3GPP network. When UE is switched from a 3GPP network to a non-3GPP network, a non-3GPP GW network element acquires APN and PGW address information used by the UE in the 3GPP network from an HSS, for each APN and PGW record, the non-3GPP GW sends a proxy binding update message to a PGW to initiate a PDN connection establishment program, and PDN connection established by the UE in the 3GPP network is established in the non-3GPP network.

Therefore, in the prior art, different PDN connections correspond to different APNs, and an APN can uniquely identify a PDN connection, and in actual operation, it often occurs that multiple PDN connections use the same APN and the same PGW, and in this case, the PDN connection cannot be uniquely identified according to the APN, so that the PDN connection cannot be located, and network processing is abnormal.

Disclosure of Invention

In view of this, embodiments of the present invention provide a method for processing a PDN connection, so as to solve a problem in the prior art that when multiple PDN connections use the same APN and the same PGW, the PDN connection cannot be located.

A method for processing a Packet Data Network (PDN) connection comprises the following steps: receiving a PDN connection request initiated by User Equipment (UE); and allocating a PDN connection identifier for the PDN connection request, wherein the PDN connection identifier is used for identifying the PDN connection.

An embodiment of the present invention further provides a communication terminal, which includes:

an identifier configuration unit, configured to allocate a PDN connection identifier for a PDN connection, where the PDN connection identifier is used to identify the PDN connection;

and the PDN request unit is used for sending an attach message or a PDN connection request message containing the PDN connection identifier.

An embodiment of the present invention further provides a mobility management network element of a 3GPP network, including a message receiving unit configured to receive an attach request message or a PDN connection request message from a UE, and further including: an identifier configuration unit, configured to allocate a PDN connection identifier for the PDN connection; and the PDN request unit is used for sending a default bearer creation request message containing the PDN connection identifier.

An embodiment of the present invention further provides a non-3GPP network element, including a message receiving unit configured to receive a PDN connection request message from a UE, further including: an identifier configuration unit, configured to allocate a PDN connection identifier for a PDN connection, where the PDN connection identifier is used to identify the PDN connection; and the PDN request unit is used for sending the proxy binding update message containing the PDN connection identifier.

The embodiment of the present invention further provides a packet data network gateway PGW, including a message receiving unit configured to receive a request PDN connection, further including: an identifier configuration unit, configured to allocate a PDN connection identifier for a PDN connection, where the PDN connection identifier is used to identify the PDN connection; and the PDN request reply unit is used for sending a reply message containing the PDN connection identifier.

Therefore, for different PDN connections, one PDN connection can be positioned by using the PDN connection identifier, so that the PDN connection in the source network can be positioned according to the PDN connection identifier after the UE is switched from the source network to the target network.

Drawings

FIG. 1 is a diagram of a prior art E-UTRAN architecture;

FIG. 2 is a flow chart of a prior art access 3GPP network;

FIG. 3 is a flow chart illustrating a prior art method for requesting a PDN connection in a 3GPP network;

FIG. 4 is a flow chart of a first method of the present invention;

FIG. 5 is a flow chart of a first embodiment of the method of the present invention 1;

FIG. 6 is a flowchart of a first embodiment of the method of the present invention shown in FIG. 2;

FIG. 7 is a flowchart of a first embodiment of the method of the present invention 1;

FIG. 8 is a flowchart of a first method embodiment of the present invention, depicted in FIG. 2;

FIG. 9 is a flowchart of a first method embodiment of the present invention 3;

FIG. 10 is a flow chart of a second method of the present invention;

FIG. 11 is a flowchart of a second embodiment of the method of the present invention 1;

FIG. 12 is a flowchart of a second embodiment of the method of the present invention shown in FIG. 2;

FIG. 16 is a flowchart of a second embodiment of the method of the present invention;

FIG. 13 is a flowchart 1 of a second method embodiment of the present invention;

FIG. 14 is a flowchart of a second method embodiment of the present invention 2;

FIG. 15 is a flowchart of a second method embodiment of the present invention 3;

FIG. 17 is a flowchart of a second method embodiment of the present invention 4;

fig. 18 is a flowchart of a PDN connection processing method according to the present invention.

Detailed Description

The first method provided by the embodiment of the present invention is a registration method of PDN connection, and with reference to fig. 4, the method includes the following steps:

s401: distributing a PDN connection identifier for a PDN connection request initiated by UE;

s402: and sending PDN connection registration information containing the PDN connection identifier, the APN and the PGW address to the HSS, or sending the PDN connection registration information containing the PDN connection identifier and the PGW address to the HSS, wherein the PDN connection identifier is used for identifying one PDN connection.

Therefore, for different PDN connections, the information of the APN, the PGW address and the PDN connection identifier used by the PDN connection or the information of the PDN connection identifier and the PGW address used by the PDN connection is unique, that is, the APN, the PGW address and the PDN connection identifier or the PDN connection identifier and the PGW address information can uniquely identify one PDN connection, even if the same APN and the same PGW address correspond to a plurality of PDN connections, the records stored in the HSS are also multiple, and therefore the problem that only one PDN connection can be established in a target network and other PDN connections are lost due to the fact that only one record can be stored in the HSS in the existing scheme can be avoided.

The first method is described in detail below with reference to the accompanying drawings.

First, a first embodiment of the first method is described: a method for registering PDN connection in 3GPP network.

The UE may request to establish the PDN connection through an attach request message requesting access to the 3GPP network, or through a non-default PDN connection request message after accessing the 3GPP network. These two cases will be described separately below.

Referring to fig. 5, a flow chart of a first method embodiment is shown in fig. 1.

In a first method embodiment, as shown in a flowchart 1, when a UE accesses a 3GPP network, a mobility management network element obtains a PDN connection identifier used by a PDN connection in a procedure for establishing the PDN connection, and the mobility management network element registers an APN, a PGW address, and a PDN connection identifier used by the PDN connection to an HSS or registers a PDN GW address and a PDN connection identifier used by the PDN connection to the HSS.

Fig. 5 includes:

s501: the UE sends an Attach Request (Attach Request) message to a mobility management network element;

S502: an authentication process is executed among the UE, the mobility management network element and the HSS;

s503: the method comprises the steps that a position updating and signed data inserting process is executed between a mobility management network element and an HSS, the address of the mobility management network element is registered in the HSS, and meanwhile, the HSS inserts signed data of UE into the mobility management network element;

s504: a mobile management network element selects a PGW according to a default APN used by UE, and sends a default bearer creation request message to the SGW to create a default PDN connection, wherein the message carries the selected PGW address and APN information;

wherein, if the PDN connection identity is allocated by the mobility management network element, the mobility management network element allocates a PDN connection identity (PDN ConnectivityID) to the default PDN connection in this step to identify the PDN connection, and then carries it to the SGW in the create default bearer request message. The PDN connection identity may be unique within a UE range, or within an APN used by the UE.

S505: the SGW sends a message for creating a default load request or a proxy binding update message to the selected PGW, wherein the message carries APN information;

if the interface protocol between the SGW and the PGW uses a GTP protocol, a default bearer creation request message is used; if the interface protocol between the SGW and the PGW uses the PMIP protocol, a proxy binding update message is used. If the mobility management network element carries the PDN connectivity identity to the SGW, the SGW carries this information to the PGW.

S506: the PGW returns a default bearer response or an agent binding confirmation message to the SGW;

if the PGW allocates an IP address for the PDN connection, the message carries the IP address used by the PDN connection. If the PDN connection identifier is allocated by the PGW, the PGW allocates a PDN connection identifier for the PDN connection. If the PGW allocates a PDN connection identity to the PDN connection, the PGW carries the allocated PDN connection identity in a create default bearer response or a proxy binding acknowledgement message. The PDN connection identity may be unique within a UE range, or within an APN used by the UE.

S507: the SGW returns a default bearing response message to the mobility management network element;

and if the PGW carries the PDN connection identification information to the SGW, the SGW carries the PDN connection identifier.

S508: the mobile management network element returns an attachment receiving message to the UE, and the message carries a PDN connection identifier used by the PDN connection;

s509: a mobile management network element sends a location updating request message to an HSS, wherein the message carries APN, PGW address and PDN connection identification information of a default PDN connection used by UE or carries the PGW address and PDN connection identification information of the default PDN connection used by the UE;

s510: and the HSS stores the APN, the PGW address and the PDN connection identification information used by the UE or stores the PGW address and the PDN connection identification information used by the UE, and returns a location update response message to the mobility management network element.

It can be seen that in the first method embodiment, as shown in the flowchart 1, a PDN connection identity may be allocated to the PDN connection by a mobility management network element or a PGW.

Referring to fig. 6, a flow chart of a first method embodiment is shown in fig. 2.

In a first method embodiment, as shown in a flowchart 2, when a 3GPP network requests a PDN connection, a mobility management network element obtains a PDN connection identifier used by the PDN connection in a procedure for establishing the PDN connection, and the mobility management network element registers an APN, a PGW address, and a PDN connection identifier used by the PDN connection, or the mobility management network element registers a PDN GW address and a PDN connection identifier used by the PDN connection to an HSS.

Fig. 6 includes:

s601: UE sends a PDN connection request message to a mobile management network element to request to establish PDN connection, wherein the message carries APN used by the PDN;

if the PDN connection identity is allocated by the UE, the UE allocates a PDN connection identity for the PDN connection in this step, and then carries it to the mobility management network element in the PDN connection request message. The PDN connection identity may be unique within a UE range, or within an APN used by the UE.

For GERAN/UTRAN network, the mobile management network element is SGSN; for an E-UTRAN network, the mobility management network element is MME.

S602: and the mobile management network element selects a PGW according to the APN carried by the UE, and sends a message of creating a default bearer to the SGW to create the PDN connection, wherein the message carries the selected PGW address and APN information. And if the UE carries the PDN connection identifier in the PDN connection request message, the mobility management network element carries the PDN connection identifier in the default bearer creation request message. And if the UE does not carry the PDN connection identifier in the PDN connection request message and the PDN connection identifier is distributed by the mobility management network element, the mobility management network element distributes a PDN connection identifier for the PDN connection, and the mobility management network element carries the PDN connection identifier in the default bearer creation request message. The PDN connection identity may be unique within a UE range, or within an APN used by the UE.

S603: the SGW sends a message for creating a default load request or a proxy binding update message to the selected PGW, wherein the message carries APN information;

if the mobility management network element carries the PDN connectivity identity to the SGW, the SGW carries this information to the PGW.

S604: the PGW returns a default bearer response or an agent binding confirmation message to the SGW;

if the PGW allocates an IP address for the PDN connection, the message carries the IP address used by the PDN connection.

If the PDN connection identifier is allocated by the PGW, the PGW allocates a PDN connection identifier for the PDN connection. The PDN connection identity may be unique within a UE range, or within an APN used by the UE.

If the PGW allocates a PDN connection identity to the PDN connection, the PGW carries the allocated PDN connection identity in a create default bearer response or a proxy binding acknowledgement message.

S605: the SGW returns a default bearing response message to the mobility management network element;

and if the PGW carries the PDN connection identification information to the SGW, the SGW carries the PDN connection identification.

S606: the mobile management network element returns a PDN connection receiving message to the UE;

and if the PDN connection identifier is distributed by the mobility management network element or the PGW, the mobility management network element carries the PDN connection identifier information to the UE.

S607: a mobile management network element sends a location updating request message to an HSS, wherein the message carries APN (access point name), PGW (packet data network) address and PDN (public data network) connection identification information of a default PDN (public data network) connection used by UE (user equipment) or carries the PGW address and PDN connection identification information of the default PDN connection used by the UE;

s608: and the HSS stores the APN, the PGW address and the PDN connection identification information used by the UE or stores the PGW address and the PDN connection identification information used by the UE, and returns a location update response message to the mobility management network element.

It can be seen that in the first method embodiment and in a flowchart of fig. 2, a PDN connection identity may be allocated to a PDN connection by a UE, a mobility management network element, or a PGW.

A second embodiment of the first method is described below: a method for registering PDN connection in non-3GPP network.

The UE can request to establish the PDN connection through an attachment request message requesting to access a non-3GPP network or through a PDN connection request message after accessing the 3GPP network, wherein under the condition of establishing the PDN connection through the attachment request message, two modes of realizing the PDN connection request are realized by sending an agent binding update message to a PGW by a non-3GPP network element and directly sending the binding update message to the PGW by the UE. These three cases will be described separately below.

Referring to fig. 7, a flow diagram of a first method embodiment is shown in fig. 1.

In the first method embodiment and the flowchart 1, when the UE accesses the non-3GPP network, the PGW registers, in the procedure of establishing the PDN connection, the APN, the PGW address, and the PDN connection identifier used by the PDN connection, or the PGW registers, to the HSS, the PDN GW address and the PDN connection identifier used by the PDN connection.

Fig. 7 includes:

s701: authentication and authentication are executed among the UE, the non-3GPP GW, the AAA Server and the HSS;

for the WLAN system, the non-3GPP GW is an Evolved Packet Data Gateway (EPDG); for the Wimax system, the non-3GPP GW is an Access Service Network Gateway (ASN GW); for a CDMA system, the non-3GPP GW is an Access Gateway (AGW).

S702: UE sends layer 3 attach request message to non-3GPP GW;

s703: if a PMIP protocol is used in the non-3GPP network, the non-3GPP GW selects a PGW according to a default APN used by the UE, then sends a proxy binding update message to the selected PGW to establish default PDN connection, and the message carries APN information; if the PDN connection identifier is allocated by the non-3GPP GW, the non-3GPP GW allocates a PDN connection identifier for the PDN connection in the step, and then carries the PDN connection identifier to the PGW in the agent binding update message; the PDN connection identity may be unique within a UE range, or within an APN used by the UE.

S704: if the non-3GPP GW does not allocate the PDN connection identification for the PDN connection, the PGW allocates the PDN connection identification for the PDN connection. The PDN connection identity may be unique within a UE range, or within an APN used by the UE.

The PGW sends a PGW address updating message to the AAA Server, the AAA Server sends a PGW address updating message to the HSS, and the information of the PDN connection is registered to the HSS; wherein, the message carries the APN, PGW address and PDN connection identifier used by the PDN connection, or the message carries the PDN GW address and PDN connection identifier used by the PDN connection;

s705: the PGW returns a proxy binding acknowledgement message to the non-3GPP GW;

and if the PDN connection identifier is distributed to the PDN connection by the PGW, carrying the PDN connection identifier by the PGW in the proxy binding confirmation message.

S706: and the non-3GPP GW sends a layer 3 attachment acceptance message to the UE, wherein the message carries a PDN connection identifier.

It can be seen that in the first method embodiment and in the flowchart 1, a PDN connection identity may be allocated to the PDN connection by a non-3GPP network element or a PGW.

Referring to fig. 8, a flow chart of a first method embodiment is shown in fig. 2.

In the first method embodiment and the flowchart 2, when the UE accesses the non-3GPP network, the PGW registers, in the procedure of establishing the PDN connection, the APN, the PGW address, and the PDN connection identifier used by the PDN connection, or the PGW registers, to the HSS, the PDN GW address and the PDN connection identifier used by the PDN connection. Unlike the first method embodiment, in which the non-3GPP network element sends the proxy binding update message to the PGW in the flowchart 1, in this fig. 8, the UE directly sends the binding update message to the PGW.

Fig. 8 includes:

s801: authentication and authentication are executed among the UE, the non-3GPP GW, the AAA Server and the HSS;

s802: UE sends layer 3 attach request message to non-3GPP GW;

s803: if CMIP protocol is used in non-3GPP network, then non-3GPP GW returns layer 3 attachment acceptance message to UE;

s804: if the CMIP protocol is used in the non-3GPP network, the UE sends a binding update message to a PGW to establish default PDN connection, and the message carries APN information; if the PDN connection identity is allocated by the UE, the UE allocates a PDN connection identity for the PDN connection in this step, and then carries it to the PGW in the binding update message; the PDN connection identity may be unique within a UE range, or within an APN used by the UE.

S805: if the PDN connection identity is allocated by the PGW, the PGW allocates a PDN connection identity for this PDN connection. The PDN connection identity may be unique within a UE range, or within an APN used by the UE.

And the PGW sends a PGW address updating message to the AAA Server, the AAA Server sends a PGW address updating message to the HSS and registers the information of the PDN connection to the HSS, wherein the message carries the APN, the PGW address and the PDN connection identifier used by the PDN connection or the message carries the PDN GW address and the PDN connection identifier used by the PDN connection.

S806: the PGW sends a binding confirmation message to the UE;

and if the PDN connection identifier is distributed to the PDN connection by the PGW, carrying the PDN connection identifier by the PGW in the binding confirmation message.

It can be seen that in the first method embodiment and in the flowchart of fig. 2, the PDN connection identity may be allocated by the UE or the PGW.

Referring to fig. 9, a flow chart of a first method embodiment is shown in fig. 3.

In the first method embodiment and the flowchart 3, when a UE requests a PDN connection from a non-3GPP network, a PGW registers an APN, a PGW address, and a PDN connection identifier used by the PDN connection, or the PGW registers a PDN GW address and a PDN connection identifier used by the PDN connection with an HSS.

Fig. 9 includes:

s901: if the PMIP protocol is used in the non-3GPP network, the UE sends a PDN connection request message to the non-3GPP GW, and the message carries APN information used by the PDN connection; if the PDN connection identifier is allocated by the UE, the UE allocates a PDN connection identifier for the PDN connection in the step and then carries the PDN connection identifier to the non-3GPP GW in a PDN connection request message; the PDN connection identity may be unique within a UE range, or within an APN used by the UE.

S902: the non-3GPP GW selects a PGW according to the APN, and then sends a proxy binding update message to the selected PGW to establish PDN connection;

and if the UE carries the PDN connection identifier in the PDN connection request message, the non-3GPP GW carries the PDN connection identifier in the proxy binding update message.

And if the UE does not carry the PDN connection identifier in the PDN connection request message and the PDN connection identifier is distributed by the non-3GPP GW, the non-3GPP GW distributes a PDN connection identifier for the PDN connection, and the non-3GPP GW carries the PDN connection identifier in the proxy binding update message. The PDN connection identity may be unique within a UE range, or within an APN used by the UE.

S903: if the PDN connection identity is allocated by the PGW, the PGW allocates a PDN connection identity for this PDN connection. The PDN connection identity may be unique within a UE range, or within an APN used by the UE.

The PGW sends a message for updating the PGW address to the AAA Server, the AAA Server sends a message for updating the PGW address to the HSS and registers the information of the PDN connection to the HSS, wherein the message carries the APN, the PGW address and the PDN connection identifier used by the PDN connection or the message carries the PDN GW address and the PDN connection identifier used by the PDN connection;

s904: the PGW returns a proxy binding acknowledgement message to the non-3GPP GW;

and if the PDN connection identifier is distributed to the PDN connection by the PGW, carrying the PDN connection identifier by the PGW in the agent binding update message.

S905: a non-3GPP GW sends a PDN connection acceptance message to a UE;

and if the PDN connection identifier is distributed by the non-3GPP GW or the PGW, the non-3GPP GW carries the PDN connection identifier in the PDN connection receiving message.

It can be seen that in the first method embodiment and in the flowchart 3, a PDN connection identity may be allocated to a PDN connection by the UE, a non-3GPP network element, or a PGW.

The second method provided by the embodiment of the invention is a method for allocating an IP address of a PDN connection and establishing the PDN connection in a target network.

Referring to fig. 10, allocating an IP address of a PDN connection comprises the steps of:

s1001: after receiving a message requesting to establish a PDN connection, a PGW searches an IP address of a pre-established PDN connection according to an APN and PDN connection identification information carried in the message or the PDN connection identification information carried in the message;

s1002: the PGW allocates an IP address of the queried PDN connection.

In order to ensure the service continuity when the UE is switched between the 3GPP network and the non-3GPP network, the IP address in the PDN connection used by the UE after the UE is switched to the target network needs to be kept unchanged. That is, when the UE switches between the 3GPP network and the non-3GPP network, after the PDN connection request message initiated by the mobility management network element or the non-3GPP gw network element or the UE is sent to the PGW, the PGW needs to use the IP address allocated when the PDN connection is connected to the source network. For different PDN connections, different IP addresses are allocated on the PGW for the UE. So if multiple PDN connections of a UE use the same APN, then the APN used by this UE on the PGW has multiple IP addresses. Therefore, when the PGW passes through the PDN connection identifier and the APN, the existing PDN connection IP address can be found, the UE cannot be switched to the wrong destination IP address, and the PGW is ensured to process normally.

Meanwhile, the embodiment of the invention also provides a method for establishing the PDN connection, which comprises the following steps:

1. the method comprises the steps of obtaining a PDN connection identifier, an APN and PGW address information which are established by UE in a source network, or obtaining the PDN connection identifier and the PGW address information which are established by the UE in the source network;

2. and establishing PDN connection in a target network according to the PDN connection identifier, the APN and the PGW address information or according to the PDN connection identifier and the PGW address information.

By adopting the PDN connection establishment method, the PGW and the UE device, the PDN connection can be established in the target network by utilizing the PDN connection information of the source network, and the problem that in the existing scheme, when a plurality of PDN connections use the same APN and the same PGW, only one PDN connection can be established in the target network, so that other PDN connections are lost is solved, and the completeness and continuity of the service are ensured.

The second method will be described in detail below with reference to the accompanying drawings.

First, a first embodiment of the second method is described: PDN connection establishment method in the process of switching from non-3GPP network to 3GPP network.

Referring to fig. 11, a flow chart of a second method embodiment is shown in fig. 1.

In a second method embodiment, as shown in a flowchart 1, when a UE is switched from a non-3GPP network to a 3GPP network or the UE needs to be switched from the non-3GPP network to the 3GPP network, an MME acquires PDN connection record used by the UE in the non-3GPP network, and for each PDN connection record, the MME initiates a PDN connection establishment procedure, and notifies the APN and the PDN connection identifier of the PDN connection to a PGW or notifies the PDN GW of the PDN connection identifier of the PDN connection. And the PGW locates the PDN connection used by the UE according to the APN and the PDN connection identifier or the PDNGW according to the PDN connection identifier and keeps the IP address of the PDN connection unchanged.

Fig. 11 includes:

s1101: UE is accessed in non-3GPP, and initiates the switching from non-3GPP network to 3GPP network;

s1102: the UE is switched to a 3GPP network, and the UE sends an attachment request message to a mobility management network element through an access network element of the 3GPP network; or the UE needs to be switched to the 3GPP network, but the UE also resides in the non-3GPP network, and then the UE sends an attachment request message to a mobility management network element through a network element of the non-3GPP network;

the UE carries an identifier in the Attach request message to indicate that the Attach request is an Attach request caused by Handover, for example, the UE sets an Attach Type cell in the message to a Handover Attach.

S1103: executing authentication flow among the UE, the mobility management network element and the HSS;

s1104: the method comprises the steps that a position updating and signed data inserting process is executed between a mobility management network element and an HSS, the address of the mobility management network element is registered in the HSS, and simultaneously the HSS inserts signed data of UE into the mobility management network element;

in this step, the HSS issues PDN connection information used by the UE in the non-3GPP network to the mobility management element, that is, the mobility management element obtains an APN, a PGW address, and PDN connection identification information used by the UE in the non-3GPP network, or the mobility management element obtains a PDN GW address and PDN connection identification information used by the UE in the non-3GPP network.

S1105: the mobility management network element identifies that an attach request message of the UE is an attach request caused by switching, the mobility management network element initiates a PDN connection establishment program for each obtained APN, PGW address and PDN connection identification record or the mobility management network element initiates a PDN connection establishment program for each obtained PDN GW address and PDN connection identification record, and for each PDN connection establishment program, the mobility management network element sends a default bearer establishment request message to an SGW, wherein the message carries the PGW address, APN and PDN connection identification in the record or carries the PDN GW address and PDN connection identification in the record;

s1106: after receiving the message, the SGW sends a message for creating a default bearer request or a proxy binding update message to the PGW, wherein the message carries the APN and the PDN connection identifier or the message carries the PDN connection identifier;

S1107: for each PDN connection establishment program, the PGW returns a default bearer response or a proxy binding confirmation message to the SGW;

after receiving the message, the PGW locates the PDN connection used by the UE according to the APN, the PDN connection identity, or the PDN connection identity after receiving the message, and then the PGW keeps the IP address of the PDN connection unchanged, i.e. the PGW continues to use the IP address allocated by the UE in the non-3GPP network for the PDN connection without allocating the IP address to the PDN connection.

If the create default bearer request message or the proxy binding update message received by the PGW carries APN information without a PDN connection identifier or a new PDN connection identifier (i.e. the PDN connection identifier cannot be queried on the PGW), the PGW regards the PDN connection as a new PDN connection establishment request message, and the PGW allocates an IP address to the PDN connection (as described in fig. 5).

S1108: for each PDN connection establishment procedure, the SGW creates a default bearer response message back to the mobility management network element.

S1109: the mobility management network element returns an attach accept message to the UE.

If the PDN connection initiated by the mobility management network element is established in the non-3GPP network by the UE (namely the PDN connection establishment is initiated by the mobility management network element according to the inquired record), the mobility management network element does not need to register the information of the PDN connection to the HSS; if the PDN connection initiated by the mobility management network element is not established in the non-3GPP network by the UE, the mobility management network element registers the information (namely the APN, the PGW address and the PDN connection identifier, or the PDN GW address and the PDN connection identifier) of the PDN connection to the HSS.

Referring to fig. 12, a flow chart of a second method embodiment is shown in fig. 2.

In a second method embodiment, a flowchart 2, an MME obtains a PDN connectivity record used by a UE in a non-3GPP network when the UE is handed over from the non-3GPP network to a 3GPP network or the UE needs to be handed over from the non-3GPP network to the 3GPP network. And the UE initiates a PDN connection establishment program and notifies the APN and the PDN connection identifier of the PDN connection or the PDN connection identifier of the PDN connection to a mobility management network element. After receiving the PDN connection establishment request message of the UE, the mobility management network element obtains, according to the APN and the PDN connection identifier carried in the message or according to a query record of the PDN connection identifier carried in the message, PGW address information used for the PDN connection. And the mobile management network element initiates a PDN connection establishment program to the inquired PGW, wherein the message carries the APN used by the PDN connection and PDN connection identification information or the message carries the PDN connection identification information used by the PDN connection. And the PGW locates the PDN connection used by the UE according to the APN and the PDN connection identifier or the PDNGW according to the PDN connection identifier and keeps the IP address of the PDN connection unchanged.

Fig. 12 includes:

s1201: UE is accessed in non-3GPP, and initiates the switching from non-3GPP network to 3GPP network;

s1202: the UE is switched to a 3GPP network, and the UE sends an attachment request message to a mobility management network element through an access network element of the 3GPP network; or the UE needs to be switched to the 3GPP network, but the UE also resides in the non-3GPP network, and then the UE sends an attachment request message to a mobility management network element through a network element of the non-3GPP network;

the UE carries an identifier in the Attach request message to indicate that the Attach request is an Attach request caused by Handover (e.g., the UE sets an Attach Type cell in the message to a Handover Attach).

S1203: executing authentication flow among the UE, the mobility management network element and the HSS;

s1204: the method comprises the steps that a position updating and signed data inserting process is executed between a mobility management network element and an HSS, the address of the mobility management network element is registered in the HSS, and simultaneously the HSS inserts signed data of UE into the mobility management network element;

S1205: the mobility management network element returns an attachment acceptance message to the UE;

s1206: for each PDN connection, the UE sends a PDN connection request message to a mobility management network element to request establishment of the PDN connection. The message carries an APN used by PDN connection, a PDN connection identifier or the message carries a PDN connection identifier used by PDN connection;

s1207: after receiving the message, the mobility management network element acquires a PGW address corresponding to the APN and the PDN connection identifier or acquires a PDN GW address corresponding to the PDN connection identifier according to the APN and the PDN connection identifier carried in the message or a PDN connection identifier query record carried in the message;

and the mobility management network element sends a default load request message to the SGW to request PDN connection creation, wherein the default load request message carries APN, PDN connection identification and PGW address information or PDN connection identification and PDN GW address information. .

S1208: after receiving the message, the SGW sends a default bearer creation request message or an agent binding update message to the PGW, wherein the message carries APN (access point name), PDN (public data network) connection identification information or PDN connection identification information;

S1209: for each PDN connection establishment program, the PGW returns a default bearer response or a proxy binding confirmation message to the SGW;

after receiving the message, the PGW locates the PDN connection used by the UE according to the APN, the PDN connection identifier, or the PDN connection identifier, and then the PGW keeps the IP address of the PDN connection unchanged, that is, the PGW continues to use the IP address allocated by the UE in the non-3GPP network for the PDN connection without allocating the IP address to the PDN connection.

If the created default bearer request message or the proxy binding update message received by the PGW carries APN information without a PDN connection identity or a new PDN connection identity, the PGW regards this as a new PDN connection establishment request message, and the PGW allocates an IP address to this PDN connection (as described in fig. 6).

S1210: for each PDN connection establishment program, the SGW creates a default bearing response message back to the mobility management network element;

s1211: the mobile management network element returns a PDN connection receiving message to the UE;

if the PDN connection initiated by the UE is established in the non-3GPP network, the mobility management network element does not need to register the information of the PDN connection to the HSS; if the PDN connection initiated by the UE is not established in the non-3GPP network, the mobility management network element registers the information (namely APN, PGW address, PDN connection identification, or PDN GW address, PDN connection identification) of the PDN connection to the HSS.

Referring to fig. 16, a flow chart of a second method embodiment is shown in fig. 3.

In a second method embodiment, a flowchart of fig. 3, a mobility management network element or a PDN GW of a UE may also register only APN and PDN GW address information used by the UE to an HSS when the UE accesses a 3GPP network or a non-3GPP network. And when the UE is switched to the 3GPP network from the non-3GPP network or the UE needs to be switched to the 3GPP network from the non-3GPP network, the MME acquires the APN and PDN GW address information used by the UE in the non-3GPP network. For the PDN connection established by the UE in the non-3GPP network, the UE initiates a PDN connection establishment program in the 3GPP network and notifies the APN and PDN connection identification of the PDN connection to a mobility management network element. After receiving the PDN connection establishment request message of the UE, the mobility management network element acquires the PGW address information used by the PDN connection according to the APN query record carried in the message. And the mobile management network element initiates a PDN connection establishment program to the inquired PGW, and the message carries the APN used by the PDN connection and PDN connection identification information. And the PGW locates the PDN connection used by the UE according to the APN and the PDN connection identifier and keeps the IP address of the PDN connection unchanged.

Fig. 16 includes:

s1601: UE is accessed in non-3GPP, and initiates the switching from non-3GPP network to 3GPP network;

s1602: the UE is switched to a 3GPP network, and the UE sends an attachment request message to a mobility management network element through an access network element of the 3GPP network; or the UE needs to be switched to the 3GPP network, but the UE also resides in the non-3GPP network, and then the UE sends an attachment request message to a mobility management network element through a network element of the non-3GPP network;

S1603: executing authentication flow among the UE, the mobility management network element and the HSS;

s1604: the method comprises the steps that a position updating and signed data inserting process is executed between a mobility management network element and an HSS, the address of the mobility management network element is registered in the HSS, and simultaneously the HSS inserts signed data of UE into the mobility management network element;

in this step, the HSS issues PDN address information used by the UE in the non-3GPP network to the mobility management element, that is, the mobility management element obtains APN and PGW address information used by the UE in the non-3GPP network.

S1605: the mobility management network element returns an attachment acceptance message to the UE;

s1606: for each PDN connection, the UE sends a PDN connection request message to a mobility management network element to request establishment of the PDN connection. The message carries APN and PDN connection identification used by PDN connection;

s1607: after receiving the message, the mobility management network element acquires a PGW address corresponding to the APN according to the APN query record carried in the message;

and the mobile management network element sends a default load request message to the SGW to request PDN connection creation, wherein the default load request message carries APN, PDN connection identification and PGW address information.

S1608: after receiving the message, the SGW sends a message for creating a default bearer request or a proxy binding update message to the PGW, wherein the message carries APN and PDN connection identification information;

S1609: for each PDN connection establishment program, the PGW returns a default bearer response or a proxy binding confirmation message to the SGW;

after receiving the message, the PGW locates the PDN connection used by the UE according to the APN and the PDN connection identity, and the PGW keeps the IP address of the PDN connection unchanged, that is, the PGW continues to use the IP address allocated by the UE in the non-3GPP network for the PDN connection without allocating the IP address to the PDN connection.

And if the created default bearer request message or the proxy binding update message received by the PGW carries the APN information and does not have the PDN connection identifier or a new PDN connection identifier, the PGW considers that the message is a new PDN connection establishment request message, and the PGW allocates an IP address for the PDN connection.

S1610: for each PDN connection establishment program, the SGW creates a default bearing response message back to the mobility management network element;

s1611: the mobile management network element returns a PDN connection receiving message to the UE;

if the PDN connection initiated by the UE is established in the non-3GPP network, the mobility management network element does not need to register the information of the PDN connection to the HSS; if the PDN connection initiated by the UE is not established in the non-3GPP network, the mobility management network element registers the information (namely APN, PGW address) of the PDN address to the HSS.

A second method embodiment is described below: a PDN connection establishment method in handover from a 3GPP network to a non-3GPP network or from a 3GPP network is required.

Referring to fig. 13, a flow diagram of a second method embodiment is shown in fig. 1.

In the second method embodiment, as shown in the flowchart 1, when the UE is switched from the 3GPP network to the non-3GPP network or needs to be switched from the 3GPP network to the non-3GPP network, the non-3GPP GW obtains PDN connection record used by the UE in the 3GPP network, and for each PDN connection record, the non-3GPP GW initiates a PDN connection establishment procedure, and notifies the APN and PDN connection identifier of the PDN connection or the PDN connection identifier of the PDN connection to the PGW. And the PGW locates the PDN connection used by the UE according to the APN and the PDN connection identifier or the PDN connection identifier and keeps the IP address of the PDN connection unchanged.

Fig. 13 includes:

s1301: UE is accessed in a 3GPP network and initiates the switching from the 3GPP network to a non-3GPP network;

s1302: authentication and authentication are executed among the UE, the non-3GPP GW, the AAA Server and the HSS;

the non-3GPP GW acquires PDN connection information used by the UE in the 3GPP network in this step, that is, the non-3GPP GW acquires an APN, a PGW address, and PDN connection identification information used by the UE in the 3GPP network, or the non-3GPP GW acquires a PDN GW address and PDN connection identification information used by the UE in the 3GPP network.

S1303: if the PMIP protocol is used in the non-3GPP network, the UE sends a layer 3 attach request message to the non-3GPP GW, and the message can carry indication bit information to indicate that the layer 3 attach request message is caused by switching;

s1304: the non-3GPP GW initiates a PDN connection establishment program for each obtained APN, PGW address and PDN connection identification record or each obtained PDN GW address and PDN connection identification, and for each PDN connection establishment program, the non-3GPP GW sends an agent binding update message to the PGW, wherein the message carries APN and PDN connection identification information in the record or carries PDN connection identification information in the record;

s1305: for each PDN connection establishment procedure, the PGW returns a proxy binding acknowledgement message to the non-3GPP GW;

after receiving the message, the PGW locates the PDN connection used by the UE according to the APN, the PDN connection identifier, or the PDN connection identifier, and then the PGW keeps the IP address of the PDN connection unchanged, that is, the PGW continues to use the IP address allocated by the UE in the 3GPP network for the PDN connection without allocating the IP address to the PDN connection.

And if the proxy binding update message received by the PGW carries APN information and does not have a PDN connection identifier or a new PDN connection identifier, the PGW considers that the message is a new PDN connection establishment request message, and the PGW allocates an IP address for the PDN connection.

If the PDN connection initiated by the non-3GPP GW is established in the 3GPP network by the UE, the PGW does not need to register the information of the PDN connection to the HSS; if the PDN connection initiated by the non-3GPP GW is not established in the 3GPP network by the UE, the PGW registers the information (namely APN, PGW address, PDN connection identification, or PDN GW address and PDN connection identification) of the PDN connection to the HSS.

S1306: the non-3GPP GW sends a layer 3 attach accept message to the UE.

Referring to fig. 14, a flow chart of a second method embodiment is shown in fig. 2.

When UE is switched to a non-3GPP network from a 3GPP network or needs to be switched to the non-3GPP network from the 3GPP network, a non-3GPP GW acquires PDN connection records used by the UE in the 3GPP network, for each PDN connection record, the UE initiates a PDN connection establishment program, and notifies the APN and the PDN connection identification of the PDN connection or the PDN connection identification of the PDN connection to a PGW. And the PGW locates the PDN connection used by the UE according to the APN and the PDN connection identifier or the PDN connection identifier and keeps the IP address of the PDN connection unchanged.

Fig. 14 includes:

s1401: UE is accessed in a 3GPP network and initiates the switching from the 3GPP network to a non-3GPP network;

s1402: authentication and authentication are executed among the UE, the non-3GPP GW, the AAA Server and the HSS;

S1403: UE sends layer 3 attach request message to non-3GPP GW;

s1404: if CMIP protocol is used in non-3GPP network, then non-3GPP GW returns layer 3 attachment acceptance message to UE;

s1405: for each PDN connection established by the UE in the 3GPP network, the UE sends a binding update message to a PGW to establish the PDN connection, wherein the message carries APN (access point name) used by the PDN connection, PDN connection identification information or PDN connection identification information used by the PDN connection;

s1406: for each PDN connection establishment procedure, the PGW sends back a binding acknowledgement message to the UE.

In step S1406, after receiving the message, the PGW locates the PDN connection used by the UE according to the APN, the PDN connection identifier, or the PDN connection identifier, and then the PGW keeps the IP address of the PDN connection unchanged, that is, the PGW continues to use the IP address allocated by the UE in the 3GPP network for the PDN connection without allocating the IP address to the PDN connection. And if the binding update message received by the PGW carries the APN information and does not have the PDN connection identifier or a new PDN connection identifier, the PGW considers that the message is a new PDN connection establishment request message, and the PGW allocates an IP address for the PDN connection. If the PDN connection initiated by the UE is established in the 3GPP network, the PGW does not need to register the information of the PDN connection to the HSS; if the PDN connection initiated by the UE is not established in the 3GPP network, the PGW registers information of the PDN connection (i.e., APN, PGW address, and PDN connection identity, or PDN GW address and PDN connection identity) to the HSS.

Referring to fig. 15, a flow chart of a second method embodiment is shown in fig. 3.

In a second method embodiment, as shown in flowchart 3, when a UE is switched from a 3GPP network to a non-3GPP network or needs to be switched from the 3GPP network to the non-3GPP network, a non-3GPP GW obtains PDN connection records used by the UE in the 3GPP network, and for each PDN connection record, the UE initiates a PDN connection establishment procedure to notify the non-3GPP GW of an APN, a PDN connection identifier, or a PDN connection identifier of the PDN connection. And the non-3GPP GW acquires the PGW address information used by the PDN connection according to the APN, the PDN connection identification information or the PDN connection identification information query record. And the non-3GPP GW sends an agent binding update message to the obtained PGW, wherein the message carries APN (access point name) and PDN (public data network) connection identification used by PDN (public data network) connection or PDN connection identification information used by PDN connection. And the PGW locates the PDN connection used by the UE according to the APN and the PDN connection identifier or the PDN connection identifier and keeps the IP address of the PDN connection unchanged.

Fig. 15 includes: (original picture 13)

S1501: UE is accessed in a 3GPP network and initiates the switching from the 3GPP network to a non-3GPP network;

s1502: authentication and authentication are executed among the UE, the non-3GPP GW, the AAA Server and the HSS;

S1503: UE sends layer 3 attach request message to non-3GPP GW;

s1504: the non-3GPP GW returns a layer 3 attachment acceptance message to the UE;

s1505: for each PDN connection established by the UE in the 3GPP network, the UE sends a PDN connection request message to a non-3GPP GW to establish the PDN connection, wherein the message carries APN used by the PDN connection, PDN connection identification information or PDN connection identification information used by the PDN connection;

s1506: after receiving the message, the non-3GPP GW queries a record according to the APN and the PDN connection identification information in the message or according to the PDN connection identification information in the message, and acquires a PGW address used by the PDN connection; the non-3GPP GW sends an agent binding update message to the acquired PGW, wherein the message carries the APN and PDN connection identification information in the record or carries the PDN connection identification information in the record;

s1507: for each PDN connection establishment procedure, the PGW returns a proxy binding acknowledgement message to the non-3GPP GW;

after receiving the message, the PGW locates the PDN connection used by the UE according to the APN, the PDN connection identifier, or the PDN connection identifier, and then the PGW keeps the IP address of the PDN connection unchanged, that is, the PGW continues to use the IP address allocated by the UE in the 3GPP network for the PDN connection without allocating the IP address to the PDN connection. And if the proxy binding update message received by the PGW carries APN information and does not have a PDN connection identifier or a new PDN connection identifier, the PGW considers that the message is a new PDN connection establishment request message, and the PGW allocates an IP address for the PDN connection.

S1508: the non-3GPP GW sends a PDN connection acceptance message to the UE.

Referring to fig. 17, a flow chart of a second method embodiment is shown in fig. 4.

In a second method embodiment flowchart 4, a mobility management network element or PDN GW may register only APN and PDN GW address information used by a UE to a HSS when the UE accesses a 3GPP network or a non-3GPP network. When UE is switched to a non-3GPP network from a 3GPP network or needs to be switched to the non-3GPP network from the 3GPP network, a non-3GPP GW acquires PDN address records used by the UE in the 3GPP network, for each PDN connection record, the UE initiates a PDN connection establishment program, and notifies the APN and PDN connection identification of the PDN connection to the non-3GPP GW. And the non-3GPP GW acquires the PGW address information used by the PDN connection according to the APN information query record. And the non-3GPP GW sends an agent binding update message to the obtained PGW, wherein the message carries APN used by PDN connection and PDN connection identification information. And the PGW locates the PDN connection used by the UE according to the APN and the PDN connection identifier and keeps the IP address of the PDN connection unchanged.

Fig. 17 includes:

s1701: UE is accessed in a 3GPP network and initiates the switching from the 3GPP network to a non-3GPP network;

s1702: authentication and authentication are executed among the UE, the non-3GPP GW, the AAA Server and the HSS;

the non-3GPP GW acquires PDN address information used by the UE in the 3GPP network in this step, that is, the non-3GPP GW acquires APN and PGW address information used by the UE in the 3GPP network.

S1703: UE sends layer 3 attach request message to non-3GPP GW;

s1704: the non-3GPP GW returns a layer 3 attachment acceptance message to the UE;

s1705: for each PDN connection established by the UE in the 3GPP network, the UE sends a PDN connection request message to a non-3GPP GW to establish the PDN connection, and the message carries APN used by the PDN connection and PDN connection identification information;

s1706: after receiving the message, the non-3GPP GW inquires a record according to the APN information in the message, and acquires a PGW address used by the PDN connection; the non-3GPP GW sends an agent binding update message to the acquired PGW, wherein the message carries APN and PDN connection identification information in the record;

s1707: for each PDN connection establishment procedure, the PGW returns a proxy binding acknowledgement message to the non-3GPP GW;

after receiving the above message, the PGW locates the PDN connection used by the UE according to the APN and the PDN connection identifier, and then the PGW keeps the IP address of the PDN connection unchanged, that is, the PGW continues to use the IP address allocated by the UE in the 3GPP network for the PDN connection without allocating the IP address to the PDN connection. And if the proxy binding update message received by the PGW carries APN information and does not have a PDN connection identifier or a new PDN connection identifier, the PGW considers that the message is a new PDN connection establishment request message, and the PGW allocates an IP address for the PDN connection.

If the PDN connection initiated by the non-3GPP GW is established in the 3GPP network by the UE, the PGW does not need to register the information of the PDN connection to the HSS; if the PDN connection initiated by the non-3GPP GW is that the UE is not established in the 3GPP network, the PGW registers information of the PDN address (i.e. APN, PGW address) to the HSS.

S1708: the non-3GPP GW sends a PDN connection acceptance message to the UE.

It should be noted that, in each embodiment provided by the present invention, a PDN connection is uniquely identified by a PDN connection identifier, an APN, and a PGW address, or by a PDN connection identifier and a PGW address, in an actual implementation, one PDN connection may also be uniquely identified in another manner, for example, a PDN connection is uniquely identified by an IP address, an APN, and a PGW address used by the PDN connection, or a PDN connection is uniquely identified by an IP address type (IPv4 or IPv6 or IPv4/IPv6 type), an APN, and a PGW address used by the PDN connection, a processing method of the method is the same as that in this patent embodiment, but the PDN connection identifier in the embodiment is replaced by an IP address used by the PDN connection or by an IP address type used by the PDN connection, which is not limited in this embodiment of the present invention.

It should be noted that, in each embodiment provided by the present invention, the PDN connection identifier may be an independent cell, and in an actual implementation, the PDN connection identifier may also be appended to the APN cell, for example, the PDN connection identifier is identified by an APN + sequence number (the sequence number here is the PDN connection identifier described in the embodiment of the present invention), and the embodiment of the present invention does not limit this.

It should be noted that, in each embodiment provided by the present invention, the PGW address is registered in the HSS, and in actual implementation, the FQDN (Fully Qualified domain name) information of the PGW may also be registered in the HSS, and a subsequent mobility management network element or non-3GPP gateway network element obtains the FQDN information of the PGW, and may obtain the PGW address used by the UE according to the FQDN. Regardless of whether the PGW address information or the FQDN information of the PGW is the PGW used for identifying the UE, the embodiment of the present invention is referred to as PGW identification information, that is, the PGW address in the above embodiment may also be PGW identification information of other PGWs that can identify the UE.

Corresponding to the first method, embodiments of the present invention provide various apparatuses, including apparatuses located at a UE side, a mobility management network element side in a 3GPP network, a non-3GPP network element side, a PGW side, and an HSS side, which are respectively described below.

The PDN connection registration apparatus located at the UE side according to the embodiment of the present invention may be the UE itself, or a functional entity located inside the UE, and may be implemented by software, hardware, or a combination of software and hardware. Specifically, the apparatus includes: an identifier configuration unit, configured to allocate a PDN connection identifier for the PDN connection; and the PDN request unit is used for sending an attach message or a PDN connection request message containing the PDN connection identifier.

The PDN connection registration apparatus located at the mobility management network element side of the 3GPP network provided in the embodiment of the present invention may be a mobility management network element itself, or a functional entity located inside the mobility management network element, and may be implemented by software, hardware, or a combination of software and hardware. Specifically, the apparatus includes: a message receiving unit for receiving an attach request message or a PDN connectivity request message from a UE, further comprising: an identifier configuration unit, configured to allocate a PDN connection identifier for the PDN connection; and the PDN request unit is used for sending a default bearer creation request message containing the PDN connection identifier. Wherein the mobility management network element comprises an MME or an SGSN.

The PDN connection registration apparatus located in the non-3GPP network element provided in the embodiment of the present invention may be the non-3GPP network element itself, or may be a functional entity located in the non-3GPP network element, and may be implemented by software, hardware, or a combination of software and hardware. Specifically, the apparatus includes: a message receiving unit for receiving a PDN connectivity request message from a UE, further comprising: an identifier configuration unit, configured to allocate a PDN connection identifier for the PDN connection; and the PDN request unit is used for sending the proxy binding update message containing the PDN connection identifier. The non-3GPP network element refers to EPDG, ASN GW or AGW.

The PDN connection registration apparatus located at the PGW side according to the embodiment of the present invention may be the PGW itself, or a functional entity located inside the PGW, and may be implemented by software, hardware, or a combination of software and hardware. Specifically, the apparatus includes: a message receiving unit for receiving a request for a PDN connection, further comprising: an identifier configuration unit, configured to allocate a PDN connection identifier for the PDN connection; and the PDN request reply unit is used for sending a reply message containing the PDN connection identifier. Wherein, the PDN request replying unit replies to the SGW with a create default bearer response message, a binding acknowledgement message, or a proxy binding acknowledgement message.

The PDN connection registration apparatus located at the HSS side provided in the embodiment of the present invention may be the HSS itself, or a functional entity located inside the HSS, and may be implemented by software, hardware, or a combination of software and hardware. Specifically, the apparatus includes: a message receiving unit, configured to receive a message including a PDN connection identifier, an APN, and PGW address information, or receive a message including a PDN connection identifier and PGW address information; and the storage unit is used for storing the PDN connection identifier, the APN and the PGW address information or storing the PDN connection identifier and the PGW address information. Wherein, the message receiving unit receives a message containing the PDN connection identifier, the APN, and the PGW address information from a mobility management network element or an AAA server, or the message receiving unit receives a message containing the PDN connection identifier and the PGW address information from a mobility management network element or an AAA server.

Corresponding to the second method, the embodiment of the present invention further provides an apparatus located at the PGW side. The PDN connection establishment apparatus located on the PGW side may be the PGW itself, or a functional entity located inside the PGW, and may be implemented by software, hardware, or a combination of software and hardware. Specifically, the apparatus includes: a message receiving unit, configured to receive a message including a PDN connection identifier and an APN, or a message including a PDN connection identifier; a query unit, configured to query, according to the PDN connection identifier and the APN or according to the PDN connection identifier, a PDN connection established for the UE; and the IP address control unit is used for keeping the IP address of the PDN connection unchanged. In the 3GPP network, the message receiving unit of the apparatus receives a create default bearer request message or a proxy binding update message containing a PDN connection identifier and an APN from the SGW, or the message receiving unit of the apparatus receives a create default bearer request message or a proxy binding update message containing a PDN connection identifier from the SGW. In the non-3GPP network, the message receiving unit of the device receives a proxy binding update message containing a PDN connection identifier and an APN from a non-3GPP network element, or the message receiving unit of the device receives a proxy binding update message containing a PDN connection identifier from a non-3GPP network element, or receives a binding update message containing a PDN connection identifier and an APN from a UE, or receives a binding update message containing a PDN connection identifier from a UE.

Corresponding to the second method, embodiments of the present invention provide various apparatuses, including an apparatus located at a UE side, a mobility management network element side in a 3GPP network, and a non-3GPP network element side, which are respectively described below.

The PDN connection establishment apparatus located at the UE side according to the embodiment of the present invention may be the UE itself, or a functional entity located inside the UE, and may be implemented by software, hardware, or a combination of software and hardware. Specifically, the apparatus includes: the information storage unit is used for storing a PDN connection identifier, an APN and PGW address information established by the UE in a source network, or acquiring the PDN connection identifier and the PGW address information established by the UE in the source network; and the PDN request unit is used for sending a message containing the PDN connection identifier for requesting to establish the PDN connection.

The PDN connection establishment apparatus located at the mobility management network element side of the 3GPP network provided in the embodiment of the present invention may be a mobility management network element itself, or a functional entity located inside the mobility management network element, and may be implemented by software, hardware, or a combination of software and hardware. Specifically, the apparatus includes: the information acquisition unit is used for acquiring PEN connection identification, APN and PGW address information established by the UE in a source network from HSS, or acquiring PDN connection identification and PGW address information established by the UE in the source network; and the PDN request unit is used for sending a default bearer creation request message containing the PDN connection identifier.

The PDN connection establishment apparatus located in the non-3GPP network element provided in the embodiment of the present invention may be the non-3GPP network element itself, or may be a functional entity located inside the non-3GPP network element, and may be implemented by software, hardware, or a combination of software and hardware. Specifically, the apparatus includes: the information acquisition unit is used for acquiring PEN connection identification, APN and PGW address information established by the UE in a source network from HSS, or acquiring PDN connection identification and PGW address information established by the UE in the source network; and the PDN request unit is used for sending a default bearer creation request message containing the PDN connection identifier. The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. A method for processing a Packet Data Network (PDN) connection, comprising:

receiving a PDN connection request initiated by User Equipment (UE);

allocating a PDN connection identifier for the PDN connection request, wherein the PDN connection identifier is used for uniquely identifying the PDN connection in the range of the UE or the APN range used by the UE;

the allocating a PDN connection identity for the PDN connection request includes:

when UE sends an attachment request message to request access to a 3GPP network or UE sends a PDN connection request message to request establishment of PDN connection in the 3GPP network, a mobile management network element receiving the attachment request message or the PDN connection request message allocates a PDN connection identifier, or after receiving the attachment request message or the PDN connection request message, the mobile management network element initiates a default bearer creation request or proxy binding update to a PGW through a Service Gateway (SGW), and the PGW allocates the PDN connection identifier; or,

when UE sends an attachment request message to request to access a non-3GPP network or UE sends a PDN connection request message to request to establish PDN connection in the non-3GPP network, a non-3GPP network element receiving the attachment request message or the PDN connection request message allocates a PDN connection identifier, or after the non-3GPP network element receives the attachment request message or the PDN connection request message, the non-3GPP network element initiates proxy binding update to a PGW, and the PGW allocates the PDN connection identifier; or,

and after the UE sends an attachment request, the UE sends a binding update message to a PGW, and the PGW distributes the PDN connection identifier after receiving the binding update message.

2. The method of claim 1, wherein the UE-initiated PDN connectivity request comprises: the attach request message sent by the UE is used to request to access a 3GPP network or a non-3GPP network, or the PDN connection request message sent by the UE is used to request to establish a PDN connection in the 3GPP or non-3GPP network.

3. The method of claim 1, further comprising:

sending PDN connection registration information containing the PDN connection identification, the APN and the PGW identification to a Home Subscriber Server (HSS); or,

and sending PDN connection registration information containing the PDN connection identifier and a packet data network gateway (PGW) identifier to a Home Subscriber Server (HSS).

4. A mobility management network element of a 3GPP network, comprising a message receiving unit configured to receive an attach request message or a PDN connection request message from a UE, further comprising:

an identifier configuration unit, configured to allocate a PDN connection identifier to a PDN connection after the message receiving unit receives the attach request message requesting to access the 3GPP network or the PDN connection request message requesting to establish a PDN connection in the 3GPP network, where the PDN connection identifier is used to uniquely identify the PDN connection in the UE range or in an APN range used by the UE;

and the PDN request unit is used for sending a default bearer creation request message containing the PDN connection identifier.

5. The mobility management network element according to claim 4, wherein the mobility management network element comprises a mobility management entity MME or a serving GPRS node SGSN.

6. The mobility management network element of claim 4, further comprising:

the mobility management network element sends PDN connection registration information containing the PDN connection identification, the APN and the PGW identification to HSS; or,

and the mobility management network element sends PDN connection registration information containing the PDN connection identifier and the PGW identifier to the HSS.

7. A non-3GPP network element comprising a message receiving unit configured to receive a PDN connectivity request message from a UE, further comprising:

an identifier configuration unit, configured to allocate a PDN connection identifier for a PDN connection after the message receiving unit receives the PDN connection request message requesting establishment of a PDN connection in a non-3GPP network, where the PDN connection identifier is used to uniquely identify the PDN connection within a UE range or within an APN range used by the UE;

and the PDN request unit is used for sending the proxy binding update message containing the PDN connection identifier.

8. The non-3GPP network element of claim 7, wherein the non-3GPP network element comprises an Evolved Packet Data Gateway (EPDG), an access service network gateway (ASN GW), or an Access Gateway (AGW).

9. A packet data network gateway (PGW) comprises a message receiving unit for receiving a request PDN connection message, wherein the request PDN connection message comprises a default bearer creation request or proxy binding update initiated by a Serving Gateway (SGW) to the PGW after an attachment request message or a PDN connection request message is received by a mobility management network element, or the proxy binding update initiated by the PGW after a non-3GPP network element receives the attachment request message or the PDN connection request message, or the binding update message sent by a User Equipment (UE) to the PGW after the UE sends the attachment request;

it is characterized by also comprising:

an identifier configuration unit, configured to allocate a PDN connection identifier to a PDN connection after the message receiving unit receives the message requesting the PDN connection, where the PDN connection identifier is used to uniquely identify the PDN connection within a UE range or within an APN range used by the UE;

and the PDN request reply unit is used for sending a reply message containing the PDN connection identifier.

10. The PGW of claim 9, wherein the PDN request replying unit is configured to reply to the SGW with a create default bearer response message, a binding acknowledgement message, or a proxy binding acknowledgement message.

11. The PGW of claim 10, further comprising:

the PGW sends PDN connection registration information containing the PDN connection identification, the APN and the PGW identification to the HSS; or,

and the PGW sends PDN connection registration information containing the PDN connection identifier and the PGW identifier to the HSS.