KR101216081B1 - Method of re-establishing IP address during handover between heterogenous networks - Google Patents

Abstract

The present invention relates to a method of resetting an IP address so that a mobile terminal can efficiently perform handover between heterogeneous networks, and a method of transferring data being received to a new access point according to the handover for continuity of services. will be. An IP address resetting method for performing handover between heterogeneous networks according to the present invention may be performed at a mobile terminal, a point of attachment, or an access router that supports a media independent handover function. Performing a handover of the second layer; And notifying the third or more layers of the fact that the handover of the second layer has been performed. The fact that the second layer performs the handover is preferably notified to a layer higher than the third layer L3 through communication between Medio Independent Handover (MIH) entities. Another feature of the present invention is to pre-configure an IP address before handover by acquiring information related to IP address setting to be used after handover through an information service.

Multimode, Mobile Terminal, Heterogeneous Network, Handover, Trigger Event

Description

Method of resetting IP address during handover between heterogeneous networks {Method of re-establishing IP address during handover between heterogenous networks}

1 is a diagram illustrating a protocol layer configuration of a mobile terminal configured in a multi-mode in the prior art.

2 is a view for explaining the functional entities and transmission protocol of the mobile terminal and the network including the MIH function in the prior art.

Fig. 3 shows the structure of a trigger model in the prior art.

Figure 4 is an exemplary view showing a trigger that occurs until the quality of the link to which the mobile terminal is currently connected in the prior art until a new link is established.

5 is a view for explaining the basic operation of the mobile IPv4 according to the prior art.

6 is a view for explaining the basic operation of the mobile IPv6 according to the prior art.

7 and 8 are diagrams for explaining an operation procedure of FMIPv6 according to the prior art.

9 is a process flow diagram of one preferred embodiment of the present invention.

11 is a process flow diagram of another preferred embodiment of the present invention.

Figure 12 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 13 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 14 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 15 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 16 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 17 is a procedure flow diagram of yet another preferred embodiment of the present invention.

18 is a process flow diagram of yet another preferred embodiment of the present invention.

Figure 19 is a procedure flow diagram of yet another preferred embodiment of the present invention.

20 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 21 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 22 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 23 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 24 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 25 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 26 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 27 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 28 is a procedure flow diagram of yet another preferred embodiment of the present invention.

Figure 29 is a procedure flow diagram of yet another preferred embodiment of the present invention.

The present invention relates to handover between heterogeneous networks. More specifically, the present invention relates to a method for resetting an IP address so that a mobile terminal can efficiently perform handover between heterogeneous networks.

IEEE802.21, which is in the international standardization of Media Independent Handover (MIH) between heterogeneous networks, provides mobile handset by providing seamless handover and service continuity between heterogeneous networks. To improve the user convenience of the device, the basic requirements are defined MIH function (MIH function), Event Trigger (Event Trigger) and Information Service (IS).

A mobile subscriber station (MSS) is a multi-mode node that supports more than one interface type. The interface type may be a wire-line interface type such as Ethernet based on IEEE802.3, a wireless interface type based on IEEE802.XX such as IEEE802.11, IEEE802.15, IEEE802.16, or 3GPP. , May be any one of interface types defined by a cellular standardization organization such as 3GPP2. However, the present invention is not limited thereto.

1 is a diagram illustrating a protocol layer configuration of a mobile terminal configured in a multi-mode. Referring to FIG. 1, a multi-mode mobile terminal has a physical layer (PHY) and a medium access control layer (MAC) layer for each mode, and a MIH layer is located below the IP layer.

Media Independent Handover (MIH) should be defined between IEEE802 series interfaces or between non-802 series interfaces such as IEEE802 series interfaces and interface types defined by cellular standardization organizations such as 3GPP and 3GPP2. Higher layer mobility support protocols such as Mobile IP (IP) and Session Initiation Protocol (SIP) should be supported for handover and seamless service.

Hereinafter, mobile IPv4 will be described. The network supporting mobile IP is composed of a home agent, a foreign agent, and a mobile terminal. The following functions are required for the operation of Mobile IP.

1) Agent Discovery

Agent discovery is a way of determining whether a mobile terminal is currently connected to its home network or located in a foreign network. By this method, the mobile terminal can detect that it has moved to another network.

2) Registration

When the registration function detects that the mobile terminal has moved to another network, the registration function provides a flexible mechanism that delivers the current location information to the home agent so that the service provided on the home network can be provided on the new network as it is.

3) Routing

The routing function is a function necessary for properly routing datagrams to be transmitted and received from or to the terminal when the mobile terminal is connected to the external network.

4) Temporary Address (CoA)

Mobile IP provides two methods, FA-CoA and co-located CoA, for temporary address setting when a mobile node moves to another subnet.

FA-CoA is provided by Foreign Agent through Agent Advertisement message, and IP address of external agent is used as temporary address. Co-located CoA is a method in which a mobile node receives a temporary address through a DHCP server located in a visited network.

Hereinafter, mobile IPv6 will be described. Mobile IPv6 supports mobility more effectively than mobile IPv4 and has superior scalability. The following is a description of basic elements and functions for the operation of Mobile IPv6.

1) Mobile Node (MN): Host or router that changes its network connection

2) Corresponding node (CN): host or router communicating with mobile node

3) Home Agent (HA): Router that has the registration information of mobile node among routers in home network and sends datagram to current location of mobile node in external network

4) Temporary address (CoA): IP address connected to the mobile node when the mobile node moves to the external network

5) Binding: Match the home address of the node with the CoA registered by the mobile node in the home agent.

6) BU (Binding Update): Used by mobile node to inform HA and CNs of its CoA.

7) BACK (Binding Acknowledge): Response message to BU

8) BR (Binding Request): A message requesting a BU if the corresponding node does not receive a BU before the mobile node's timer for binding information expires.

9) CoA Acquisition: Neighbor Discovery and Address auto-configuration can be used to automatically configure their location information when a node moves.

10) Route Optimization: After the correspondent node saves the binding information, the correspondent node can communicate with the mobile node directly without going through the home agent.

11) Address auto-configuration

Automatic generation of IP addresses includes stateful address autoconfiguration that obtains an address using a server such as DHCP, and stateless address autoconfiguration that generates an address on its own. When using a server, the host side requests an address from a DHCP server, and then assigns one of the addresses assigned by the server to the host side. The stateless address autoconfiguration method generates an address by combining its interface ID information with prefix information or well-known prefix information obtained from a router.

Hereinafter, FMIPv6 (Fast Handovers for Mobile IPv6) will be described. Fast Handovers for Mobile IPv6 (FMIPv6) is a protocol for reducing the overall handover delay in the L3 layer by speeding up mobile detection and acquisition of a new care of address (NCoA) based on handover prediction information in the L2 layer. The following describes the basic elements and messages for the operation of FMIPv6.

1) PAR (Previous Access Router): Default router before handover of mobile node

2) NAR (New Access Router): Default router expected for handover of mobile node

3) PCoA (Previous Care of Address): Valid temporary address of mobile node in PAR subnet

4) NCoA (New Care of Address): Valid temporary address of mobile node in NAR subnet

5) RtsolPr (Router Solicitation for Proxy): A message sent from a mobile node to a PAR requesting information for potential handover.

6) PrRtAdv (Proxy Router Advertisement): This message is sent from PAR to mobile node and provides information about NAVER link. It also acts as a trigger for network initiated handover.

7) Fast Binding Update (FBU): A message that a mobile node requests a PAR to change its traffic destination to NAR.

8) FBACK (Fast Binding Acknowledge): Response message to FBU generated from PAR

9) HI (Handover Initiation): A message sent from PAR to NAR indicating the handover of this node.

10) HACK (Handover Acknowledge): A message sent from NAR to PAR and response message to HI.

11) FNA (Fast Neighbor Advertisement): A message sent from the mobile node to the NAR. This message confirms the use of NCoA when the mobile node has not yet received the FBACK and informs that it has connected to a new network.

The MIH function is located below the IP layer and facilitates a handover process by using input values from Layer 2, such as a trigger event and information about another network. In addition, the MIH function may include user policy and configuration based inputs that may affect the handover process, and may include a layer 3 such as mobile IP or SIP. Generic interfaces are defined between the entity and the MIH function. These interfaces provide information about layer 1 (physical layer) and layer 2 (media access control layer) and mobility management. The MIH layer obtains information about lower layers and networks with the help of events and information services.

In the upper layer, a higher management entity for monitoring and controlling the status of various links in the mobile terminal is located to perform a handover control function and a device manager function. At this time, the handover control function and the device manager may be independently located, respectively, the two functions may be included together as a higher management entity. 2 illustrates functional entities and transmission protocols of a mobile terminal and a network including a MIH function, and a dotted line in FIG. 2 represents a primitive, an event trigger, and the like.

For fast handover, the network layer needs to use the information from the link layer so that the connection can be reestablished as soon as possible. Link layer events can help predict user movement and can help the mobile terminal and network to prepare for handover in advance.

Triggers for handover can be initiated from the physical layer (PHY), the media access control layer (MAC), and the source for these triggers can be a local stack or a remote stack. 3 shows a structure for a trigger model.

Event triggers provide a change in the state of the current signal and other network states, future predicted changes, and include changes in the physical and media access control layers or changes in the properties of a particular network.

The event type may be classified into a PHY layer event, a media access control layer event, a MAC layer event, a management event, an L3 event, an application event, and the like. .

The basic trigger events are as follows:

'Link_Up' occurs when a two-layer connection is established on a particular link interface and can transmit three-layer packets in the upper layer. At this time, it is determined that all two-layer configuration constituting the link is completed. At this time, event sources are 'Local MAC' and 'Remote MAC'. Table 1 shows the parameters of 'Link_Up'.

Name Type Description EventSource
EVENT_LAYER_TYPE Source where the event was generated EventDestination EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal MacOldAccessRouter MAC Address MAC address of the previous access router MacNewAccessRouter MAC Address MAC address of new access router NetworkIdentifer Media Specific Network identifier that can be used to detect changes in subnet

'Link_Down' occurs when a layer 2 connection is released on a particular interface and no more layer 3 packets can be sent. The event source is 'Local MAC'. Table 2 shows the parameters of 'Link_Down'.

Name Type Description EventSource
EVENT_LAYER_TYPE Source where the event was generated EventDestination
EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal MacOldAccessRouter MAC Address MAC address of the previous access router ReasonCode Reason for unlinking

'Link_Going_Down' occurs when a 2 layer connection is expected to be 'linked down' within a specific time, and may be a signal for initiating a handover procedure. Event sources are 'Local MAC' and 'Remote MAC'. Table 3 shows the parameters of 'Link_Going_Down'.

Name Type Description EventSource EVENT_LAYER_TYPE Source where the event was generated EventDestination EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal MacOldAccessRouter MAC Address MAC address of the previous access router MacNewAccessRouter MAC Address MAC address of new access router Timeinterval Time in msecs The time when the link is expected to be Link_Down ConfidenceLevel % The level at which a link is expected to be Link_Down at a specific time. UniqueEventIdentifer Used when event rollback occurs

'Link_Going_Up' occurs when a layer 2 link is expected to be 'Link_Up' within a certain time and is used when the network takes a long time to initialize. Event sources are 'Local MAC' and 'Remote MAC'. Table 4 shows the parameters of 'Link_Going_Up'.

Name Type Description EventSource EVENT_LAYER_TYPE Source where the event was generated EventDestination EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal MacNewAccessRouter MAC Address MAC address of new access router Timeinterval Time in msecs Estimated time to be Link_UP ConfidenceLevel % The level at which a link is expected to be Link_Up at a specific time UniqueEventIdentifer Used when event rollback occurs

'Link_Event_Rollback' is used in combination with 'Link_Going_Up' and 'Link_Going_Down'. Trigger that occurs when 'Link_Going_Up' or 'Link_Going_Down' is transmitted but it is predicted that 'Link_UP' or 'Link_Down' will no longer occur within a certain time. Event sources are 'Local MAC' and 'Remote MAC'. Table 5 shows the parameters of 'Link_Event_Rollback'.

Name Type Description EventSource EVENT_LAYER_TYPE Source where the event was generated EventDestination EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal MacNewAccessRouter MAC Address MAC address of new access router UniqueEventIdentifer Used when event rollback occurs

'Link_Available' indicates that a new specific link is available and indicates that the new base station or access point may provide better link quality than the base station or access point (AP) to which the mobile station is currently connected. Indicates. Event sources are 'Local MAC' and 'Remote MAC'. Table 6 shows the parameters of 'Link_Available'.

Name Type Description EventSource EVENT_LAYER_TYPE Source where the event was generated EventDestination EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal MacNewAccessRouter MAC Address MAC address of the previous access router MacOldAccessRouter MAC Address MAC address of new access router

'Link_Parameters_Change' is an event that occurs when the change of a link parameter value exceeds a certain limit level. This may include link layer parameters such as link speed, quality of service (QoS), encryption values, and the like. Event sources are 'Local MAC' and 'Remote MAC'. Table 7 shows the parameters of 'Link_Parameters_Change'.

Name Type Description EventSource EVENT_LAYER_TYPE Source where the event was generated EventDestination EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal MacAccessRouter MAC Address MAC address of current access router oldValueOfLinkParameter Previous value of link parameter newValueOfLinkParameter New value for the link parameter

'MIH_Scan' is a command used by upper layers to discover peripheral access points of the current access network. It is created when a higher layer entity requests a scan of a capable access network. If multiple links are requested, a number of Link_Scan commands can be initiated with respective media scan request information.

MIH _ Handover _Initiate.request

This primitive is used by higher layer entities to convey the intent of handover initiation between the MIH function of the mobile terminal and the MIH function of the network.

MIH _ Handover _Initiate.response

This primitive selects the preferred link and announces the information according to the status of the requested links in response to MIH_Handover_Initiate.request.

MIH _ Handover _Commit.request

It starts buffering the data that will be directed to the terminal through the previous access point as a notification to the previous access point to start the actual handover for the selected link.

MIH _ Handover _Commit.response

A response message to MIH_Handover_Commit.request may indicate whether handover is successful.

4 is an exemplary diagram illustrating a trigger generated until a quality of a link to which a mobile terminal is currently connected is degraded and a new link is established.

The Information Service provides detailed information about the network needed for network discovery and selection, and must be accessible from any network. Information services include link access parameters, security mechanisms, neighbor maps, locations, service providers and other access information, and link costs. information elements such as link).

Hereinafter, a detailed operation procedure of mobile IPv4 will be described. Mobile IPv4 aims to support transparent mobility to the upper layer by default, and requires the addition of a mobile host, a home agent, and a foreign agent to support it. However, when the path optimization is not used, the change of the correspondent node communicating with the mobile terminal is not necessary. Where a mobile host represents an IP host that is supported for mobility, and a home agent is a router that maintains location information about the mobile host and tunnels to or as a visiting agent, and a visiting agent is a router that supports mobility in the visiting network. Means each. The basic operation in mobile IPv4 can be described as shown in FIG. 5 below.

Description of each step operation in Figure 5 is as follows.

(1) When a mobile host moves from its home network to a foreign network, the mobile host recognizes that the mobile host has moved by receiving an advertisement message broadcasted from the visiting network, and the home in the home network Register a temporary address (CoA) with the agent indicating its current location

(2) At this time, the CoA is the IP address of the visited agent (FA-CoA) or the co-located CoA temporarily assigned by the mobile host through DHCP in the visited network. Packets sent from the outside to the mobile host are sent to the home network, which is intercepted by the home agent that is aware of the mobile terminal's movement.

(3) The home agent encapsulates the packet delivered to the mobile host with the FA address as the destination (when FA-CoA is used) and then forwards the packet to the visiting agent.

(4) The encapsulated and forwarded packet is de-capsulated at the visiting agent, recovered to the original forwarding packet, and finally delivered to the mobile host.

(5) A packet transmitted from the mobile host to the counterpart host may be directly transmitted through the visiting agent, or may be forwarded using a reverse tunnel when there is a problem of ingress filtering.

Key features required for mobile IP include:

(1) Agent Discovery

Agent discovery is a method of determining whether a mobile terminal is currently connected to its home network or located in a visiting network. By this method, the mobile terminal can detect that it has moved to another network.

Mobile IP extends existing Internet Control Message Protocol (ICMP) Router Discovery [IETF RFC 1256] for agent discovery. The Agent Advertisement message periodically broadcasted by an agent (home agent, visiting agent) is transmitted by including the Mobility Agent Advertisement Extension in the ICMP Router Advertisement message. The 'Agent Solicitation' message sent by the mobile station to find an agent uses the same method as the existing 'ICMP Router Solicitation' message.

(2) Registration

When the registration function detects that the mobile terminal has moved to another network, the registration function provides a flexible mechanism that delivers the current location information to the home agent so that the service provided on the home network can be provided on the new network as it is. Mobile IP defines two different registration procedures. If a mobile terminal uses a FA-CoA, it must be registered through a visiting agent. When using a co-located CoA, the mobile terminal registers directly with a home agent.

(3) Routing

The routing function defines a function necessary for properly routing datagrams to be transmitted and received from or to this terminal when the mobile terminal is connected to an external network. Datagrams include unicast as well as multicast and broadcast packets.

6 is a diagram illustrating an operation procedure of mobile IPv6. The operation procedure of the mobile IPv6 may be described sequentially in FIG.

0. MN moves from Subnet A to Subnet B.

1. MN detects movement using prefix information of RA message and neighbor unreachable detection (NUD) mechanism.

2. Obtain CoA by itself through 'Address auto-configuration' method.

3. Send BU message notifying HA of acquired CoA.

4. HA binds MN's home address and CoA and sends BAck in response to BU.

5. The CN that communicates with the MN for the first time did not detect the MN's movement, so set the destination address as the MN's home address and send the packet.

6. The HA managing the MN intercepts the packet and tunnels it to the current MN's location.

7. The MN that receives the tunneled packet determines that the CN that sent the packet does not have the binding information and sends a BU message to the CN to notify its CoA.

8. The CN stores the binding information and then communicates directly with the MN using that information.

7 and 8 are diagrams for describing an operation procedure of FMIPv6. FIG. 7 is an operation procedure of a 'Proactivie' state, and FIG. 8 shows an operation procedure of a 'Reactive' state. There are 'Proactive' states for sending and receiving FBU / FBACK messages on the link of the PAR and 'Reactive' states for sending and receiving FBU / FBACK messages from the link of the NAR . The 'Proactive' state checks the authenticity of the generated NCoA before disconnecting from the PAR. In the 'Reactive' state, the NCoA is checked after the mobile node arrives at the new subnet.

Referring to FIG. 7, an operation procedure of a 'proactive' state will be described.

1) The mobile node discovers APs capable of handover based on the L2 layer information (for example, scanning in a WLAN system) and sends a RtSolPr to the PAR to obtain subnet information corresponding to the found AP identifiers. Send a message.

2) The PAR receiving the RtSolPr message sends a PrRtAdv message to the mobile node with a tuple of [AP-ID, AR-Info] type corresponding to each subnet information corresponding to the transmitted APs. This message can sometimes be sent 'solicit' after the mobile node has detected a router.

3) Mobility creates a new temporary address (NCoA) based on the AR-Info in the PrRtAdv message.

4) The mobile node sends a FB message to the PAR to bind PCoA and NCoA so that packets arriving at the PAR can be tunneled to the NAR.

5) The PAR sends a notification message, HI, that the mobile node will hand over to the NAR. The NAR receives the HI message and performs duplicate checking of the NCoA generated by the mobile node. If the NCoA is not suitable for duplicate checking, the NAR sets a new temporary address for the mobile node.

6) The NAR sends a HACK to the PAR in response to the HI. In this case, the newly generated NCoA may be included in 6).

7) After receiving the HACK, the PAR sends a FBACK to the mobile node and the NAR, indicating that the PAR starts tunneling the mobile node's packet to the address of the actual NCoA. At this time, the connection between the mobile node and the PAR is lost.

8) Packets arriving at the PAR are forwarded to the NAR.

9) As soon as the mobile node establishes a new link with the NAR, it sends a FNA message to the NAR indicating that the node is connected to the NAR's network.

10) Packets are sent via NAR.

Referring to Fig. 8, the operation procedure of the 'Reactive' state will be described.

1) The mobile node discovers APs capable of handover based on the L2 layer information (for example, scanning in a WLAN system), and obtains subnet information corresponding to the AP identifiers (RtSolPr) found to the PAR. Send a message.

2) The PAR receiving the RtSolPr message sends a PrRtAdv message to the mobile node with a tuple of [AP-ID, AR-Info] type corresponding to each subnet information corresponding to the transmitted APs. This message can sometimes be sent 'solicit' after the mobile node has detected a router.

3) The mobile node creates a new temporary address (NCoA) based on the AR-Info in the PrRtAdv message and disconnects from the PAR.

4) As soon as the mobile node connects to the NAR, it initiates a procedure to encapsulate the FBU message in the message to the FNA so that packets arriving at the PAR are immediately forwarded to the NAR and let the NAR verify that the NCoA is valid. .

5) NAR sends a FB message to PAR to bind PCoA and NCoA. If NCoA is not valid in the FBU received by the NAR, the NAR discards the FBU packet and sends a Router Advertisement containing an alternate address.

6) PAR sends FBACK to NAR in response to FBU. At this time, tunneling setup is completed between the actual PAR and NAR.

7) Packets arriving at the PAR are forwarded to the NAR.

8) Packets are sent via NAR.

In the prior art as described above, when MIPv4, MIPv6, and FMIPv6 are used, the second layer (L2) handover and the third layer (L3) handover procedures occur independently, that is, the second layer (L2) handover is performed. Since the third layer L3 handover is performed after the execution, a delay occurs. In addition, although the second layer (L2) handover is known and the network may directly send a message for the third layer (L3) handover, but the third layer (L3) of the network does not know this problem, which requires unnecessary message transmission. have. In addition, when communication between medium-independent handover entities is possible in the field to which the present invention is applied, it may be used without changing the IP address resetting when performing handover between homogeneous networks.

The present invention has been made to solve the problems of the prior art as described above, an object of the present invention is to grasp the second layer (L2) handover in the third layer (L3) through the communication between the medium-independent handover entity. The present invention provides a method of resetting an IP address when performing handover between heterogeneous networks, which can prevent unnecessary messages, and shorten the time required for handover.

In one aspect of the present invention, a method for resetting an IP address when performing a handover between heterogeneous networks according to the present invention includes a mobile terminal and a point of attachment, for example, which support a media independent handover function. (Access Point, Base Station, etc.) or an Access Router, the method comprising: performing a handover of a second layer; And notifying the third or more layers of the fact that the handover of the second layer has been performed. The fact that the second layer performs the handover is preferably notified to a layer higher than the third layer L3 through communication between Medio Independent Handover (MIH) entities.

Hereinafter, primitives that can be used in the IP address resetting method for handover between heterogeneous networks according to the present invention, and primitives for delivering data received during handover between heterogeneous networks for service continuity to a new access point ( primitives) will be described. In addition, the primitives presented in the present invention may be used to obtain new access router information for obtaining a new IP address from an information server. Data forwarding between the old access router and the new access router described through the embodiment of the present invention is equally applicable to the communication of the primitives proposed in the present invention between the old access point and the new access points.

1) Inter_MIH.query

This primitive is a MIH signal message between access points (broadband wireless access network base station, WLAN AP, or cellular system base station), and information about a new access point is determined by a previous access point (Old PoA) of a mobile station for handover. (E.g., access router address information or access router change information, FA address information or FA information, or available resources) or a mobile terminal in which a new access point has a previous access point to a previous access point. This message is sent to request information about. If the primitive includes a delimiter (for example, an IP address, a MAC address, an ESN, etc.) for identifying a terminal to be handed over from a previous access point to a new access point, the specific access point is notified to the new access point. can do. Table 8 shows an example of the data format of the Inter_MIH.query primitive.

Name

Type
Description
CommandSource

UPPER_LAYER_TYPE
The origination point from where the command is initiated. This is usually some form of upper layer such as a policy engine, or a L3 Mobility protocol, transport, application etc.

CommandDestination

MIH_LOCAL, MIH_REMOTE

This specifies the command destination which can be either local or remote MIH Function.

CurrentLinkIdentifier

NetworkIdentifier. Can be one of different 802 and Cellular networks.
This identifies the current access network over which the command needs to be sent. This is valid only for remote commands which need to be sent to remote MIHF. The command is then sent either at L2 or at L3.

Transportlayer

TRANSPORT_L2,
TRANSPORT_L3
This identifies the transport layer L2 or L3 over which the command needs to be sent to remote MIHF entity. This is valid only for remote commands.

QueryResourceList


List of resources to be queried at the new suggested network.

2) Inter_MIH.response

This primitive is a MIH signal message between access points (broadband wireless access point base station, WLAN AP, or cellular system base station), and a new access point of a mobile station receives Inter_MIH.query from a previous access point or from a new access point. Sent to respond. When Inter_MIH.query is used for notification purpose such as initiating handover of a specific terminal, this primitive is used as its 'Acknowledge'. Table 9 shows an example of the format of the Inter_MIH.response primitive.

Name

Type
Description
CommandSource

UPPER_LAYER_TYPE
The origination point from where the command is initiated. This is usually some form of upper layer such as a policy engine, or a L3 Mobility protocol, transport, application etc.

CommandDestination

MIH_LOCAL, MIH_REMOTE

This specifies the command destination which can be either local or remote MIH Function.

CurrentLinkIdentifier

NetworkIdentifier. Can be one of different 802 and Cellular networks.
This identifies the current access network over which the command needs to be sent. This is valid only for remote commands which need to be sent to remote MIHF. The command is then sent either at L2 or at L3.

Transportlayer

TRANSPORT_L2,
TRANSPORT_L3
This identifies the transport layer L2 or L3 over which the command needs to be sent to remote MIHF entity. This is valid only for remote commands.

ResourceStatus

Specifies whether requested resources are available or not at the new PoA.

QueryResourceList


List of resources actually available at the new suggested network and the new network PoA.

3) IP_Information.request

This primitive is a MIH signaling message between access points (broadband wireless access point base station, WLAN AP, or cellular system base station, or access router), where the previous access point of the mobile station is the access router address of the new access point to the new access point. Is sent to request information (e.g., information contained in Router Advertisement) or foreign agent (FA) address information (e.g., information included in Agent Advertisement). The old access point may send directly to the access router or external agent if it has information that can reach the access router or foreign agent connected to the new access point to be moved. The previous access point may inform the new access point via this message that a particular terminal will hand over to the new access point. In addition, the MIH of the access point or foreign agent that received this primitive may trigger it to a higher layer. Table 10 shows an example of the data format of the IP_Information.request primitive. This primitive may be requested by a mobile terminal to a new access point.

Name Type Description EventSource EVENT_LAYER_TYPE Source where the event was generated EventDestination EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal MacAccessRouter MAC Address MAC address of access router New PoA MAC Address MAC Address MAC address of new connection point Home Address IP Address Home Address of Mobile Terminal CoA IP Address Temporary IP Address Currently Used by Mobile Terminal Old FA Address IP Address This parameter is included when MIPv4.
Previous FA's IP Address Old Access Router Address IP Address This parameter is included when MIPv6.
IP address of the previous Access Router

4) IP_Information.confirm

This primitive is a MIH signal message between access points (broadband wireless access network base station, WLAN AP, or cellular system base station) and is transmitted to respond to the result of a new IP_Information.request of the mobile station. This primitive contains the address information of the access router requested by IP_Information.request (for example, information included in Router Advertisement) or FA (Foreign Agent) address information (for example, information included in Agent Advertisement). Are included and transmitted.

This primitive is a MIH signal message between access points (broadband wireless access network base station, WLAN AP, or cellular system base station) and is transmitted to respond to the result of a new IP_Information.request of the mobile station. This primitive contains address information (eg, information included in Router Advertisement) or FA (Foreign Agent) address information (eg, information included in Agent Advertisement) of the access router requested by IP_Information.request. Are included and transmitted. In addition, 'TimeStamp' indicates a time when encapsulation is performed to indicate the reliability of the cached Mobility Agent Advertisement Extension or Router information. This time may indicate the time elapsed after encapsulating Agent Advertisement or Router Advertisement. The purpose of this parameter is to decapsulate the Agent Advertisement or Router Advertisement where the mobility management entity (eg Mobile IPv4, Mobile IPv6, FMIPv6, etc.) of the mobile terminal is included in the message when this message is delivered to the mobility management entity of the mobile terminal. The time indicated by the 'TimeStamp' in the life time indicating the valid time of these messages can be obtained after obtaining the information and knowing how much time has passed after this information has passed. Using the difference, you can calculate the actual lifetime of these messages.

Table 11 shows an example of the data format of the IP_Information.confirm primitive.

Name Type Description EventSource EVENT_LAYER_TYPE Source where the event was generated EventDestination EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal Mobility Management Protocol Support Type       Bitmap Indicates the Mobility Management Protocol Support type supported by the router.
0: MIPv4 with FA (FA-CoA)
1: MIPv4 without FA
(Co-located CoA) 2: MIPv6
3: MIPv6 with DHCPv6
4: FMIPv6
5: HMIPv6
6: SIP
7: Reserved IP Address Change Notification This field indicates whether the current address should be changed when the mobile station's IP address (including Care of Address) moves to a new access point.
0: IP Address Change
1: IP Address No Change FA-CoA or Router Address If the Mobility Management Protocol Support type is 0, FA-Address is included. If type is 2, Router Address is included. It is also included only when the IP Address Change Notification is 0. Mobility Agent Advertisement Extension This parameter is included only when the Mobility Management Protocol Support type is 0 and is the same information as that included in Agent Advertisement provided by FA. It is also included only when the IP Address Change Notification is 0.
(E.g. CoA information, Registration life time, encapulsation information) Router information This parameter is included only when the Mobility Management Protocol Support type is 2 and is the same information as that included in the Router Advertisement provided by the IPv6 router. It is also included only when the IP Address Change Notification is 0.
(E.g. Router Address, Stateful Auto Address Setting Method, Router Lifetime, etc.) Home Address  IP Address Home Address of Mobile Terminal Timestamp The time information when the Mobility Agent Advertisement Extension or Router information (Agent advertisement or Router advertisement) in this message is encaptulated. The time difference when this information is received and stored from the Agent or Router and when it is encapsulated in this message for transmission. .

5) IP_CoA.request

This primitive is sent after the MIH of the new access point receives IP_Information.request to request address information or an 'Agent Advertisement' message / 'Router Advertisement' message to its Access Router or FA. Table 12 shows an example of the data format of IP_CoA.request.

Name Type Description EventSource EVENT_LAYER_TYPE Source where the event was generated EventDestination EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal MacAccessRouter MAC Address MAC address of the previous access router Old FA Address IP Address This parameter is only included for MIPv4.
Previous FA's IP Address Old Access Router Address IP Address This parameter is only included for MIPv6.

6) IP_CoA.indication

This primitive is received by the Access Router or the FA's Media Independent Handover (MIH) after receiving IP_CoA.request, and then transmits the address information or 'Agent Advertisement message /' Router Advertisement 'message to the higher layer. Is sent to request. The received IP_CoA.request can be transparently transferred from the MIH to the upper layer. In this case, this primitive has the same form as IP_CoA.request.

7) IP_CoA.response

This primitive is sent in response to the MIH after the upper layer of the access router or FA has received IP_CoA.indication. This primitive contains the address information of the access router or FA or the 'Agent Advertisement' message / 'Router Advertisement' message. This parameter has the same form as in Table 9.

8) IP_CoA.confirm

This primitive is sent by the access router or FA's MIH to convey the access router, FA's address information or 'Agent Advertisement' message / 'Router Advertisement' message to the MIH of the new access point. The data format of the IP_CoA.confirm primitive may have the same form as in Table 9.

9) New_IP_Address_indication

This MIH event is used to deliver information about the new temporary address (eg, Agent Advertisement Message / Router Advertisement Message) from the previous access point to the upper layer of the mobile station. This parameter may have the same form as in Table 9.

10) IP_CoA_Info.indication

This primitive is used by the previous access router of the mobile terminal or the MIH of the FA to obtain IP-related information from the new access router or FA of the mobile terminal and deliver it to its upper layer. After receiving this primitive, the upper layer provides 'Proxy Router Advertisement' message to the mobile station. This parameter may have the same form as in Table 9.

11) Start_Data_Forwarding

This primitive is used to request that the previous access router forward the data to the new access router to the new access router after being informed that the new connection has been established by the mobile terminal. do. In addition, when the new access point is notified that the new connection is completed and the new access router is notified, the new access router may request the old access router to forward data destined for the mobile terminal to the new access router. When the data transfer request for service continuity of the mobile terminal and the data transfer are made between the access points presented through this message of the present invention, MIH functions between the access points may request the data transfer through this message. Table 13 shows an example of the format of Start_Data_Forwarding.

Name Type Description CommandSource
EVENT_LAYER_TYPE Source where the event was generated CommandDestination EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal MacOldAccessRouter MAC Address MAC address of the previous access router MacNewAccessRouter MAC Address MAC address of new access router NetworkIdentifer Media Specific Network identifier that can be used to detect changes in subnet

12) Start_Data_Transmission

This primitive informs the new access router that the new access router has completed the new link establishment with the mobile terminal and indicates that the access router can deliver data to the mobile terminal. This parameter may have the same form as in Table 11.

In order to achieve the object of the present invention, the parameters added to the existing Link_Going_Down and Link_Down are as follows.

13) Link_Going_Down

After receiving the Link_Going_Down from its MAC layer, the MIH of the mobile station includes the MAC address of the new access point in Link_Going_Down to request the IP address information of the new access point from the current access point. Table 14 shows an example of the data format of Link_Going_Down.

Name Type Description EventSource EVENT_LAYER_TYPE Source where the event was generated EventDestination EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal MacOldAccessRouter MAC Address MAC address of the previous access router MacNewAccessRouter MAC Address MAC address of new access router Timeinterval Time in msecs The time when the link is expected to be Link_Down ConfidenceLevel % The level at which a link is expected to be Link_Down at a specific time. UniqueEventIdentifer Used when event rollback occurs New poa mac MAC Address MAC address of the mobile station's new access point

14) Link_Down

By adding a new IP address of the mobile terminal to Link_Down in the prior art, the link layer of the mobile terminal's previous access point informs the MIH, and the MIH remotely triggers the remote Link_Down to the access router or FA to the new access router or FA of the mobile terminal. By transmitting the data to the new access router or FA of the mobile terminal may be requested to forward the data (forwarding) to the mobile terminal. Table 15 shows an example of the data format of Link_Down.

Name Type Description EventSource
EVENT_LAYER_TYPE Source where the event was generated EventDestination
EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal MacOldAccessRouter MAC Address MAC address of the previous access router ReasonCode Reason for unlinking Home Address IP address Home Address of Mobile Terminal CoA IP address New temporary IP address of mobile terminal

15) IP_No_Change

This primitive receives an IP_Information.Request from a mobile terminal or a previous access point of a mobile terminal at an access router that supports mobility support protocol (eg, FMIPv6), and then the mobile terminal hands over to use the old IP address at the new access point. If possible, it is used to notify its MIH. Table 16 shows an example of the data format of the IP_No_Change primitive.

Name Type Description EventSource
EVENT_LAYER_TYPE Source where the event was generated EventDestination
EVENT_LAYER_TYPE Destination to which event will be delivered MacMobileTerminal MAC Address MAC address of mobile terminal

16) Information Elements

The following defines the POA_SUBNET_INFORMATION IE related to the IP address configuration as an information element stored in the information server and delivered by the mobile terminal's request.

The POA_SUBNET_INFORMATION information element is stored in the information server and contains information about all access routers or foreign agents that connect to the access points (PoAs). That is, mapping information of layer 2 and layer 3 addresses is included. In the case of supporting IPv4, the information list including the visited agent (FA) IP address that can communicate with the current access point (PoA) may be included, and in the case of supporting IPv6, the information list including the access router (AR) IP address may be included. . If the mobile station fails to obtain a new IP address with the information (access router address) included in the POA_SUBNET_INFORMATION, the mobile station may request an IP address directly from the new router using the obtained new access router address information. Table 17 shows an example of the data format of the POA_SUBNET_INFORMATION information element.

No. Name of Information Element Description Representation Length One Type_IE_POA_SUBNET
_INFORMATION Information about subnets supported by PoA IPv4 supported: List of available FA IP addresses
IPv6 supported: List of available AR IP addresses Variable 2 Type_IE_POA_SUBNET
_INFORMATION Information about IP Address Configuration FA Address Setting Information
About AR Address Settings Variable

The construction, operation, and other features of the present invention will be readily understood by the preferred embodiments of the present invention described below with reference to the accompanying drawings.

The operation description using the method proposed by the present invention will be described as follows by handover when using mobile IPv4, and when using mobile IPv6 similar to its operation and using FMIPv6.

9 is a flow chart of a preferred embodiment of the present invention, when a mobile terminal uses MIPv4 or MIPv6 as a mobility support protocol, and uses FA-CoA or stateless address information as a temporary address, when handing over to a new access point. When a FA-CoA or a stateless address for a new access point is allocated from a previous access point, a procedure flowchart of an embodiment of acquiring a MAC address for a new access point by an information service is shown.

1) When the previous link of the mobile station deteriorates the signal quality, Link_Going_Down is transmitted to the upper layer including the upper management object through the MIH, and the Remote Link_Going_Down is transmitted to the previous access point including the address of the new access point. In this case, the MIH of the mobile station may trigger and deliver an IP_Information.Request to a previous access point instead of Remote_Link_Going_Down. The MIH instructs the lower link layers in advance to periodically scan to obtain information on the available link layer, and receives a list of candidate link layers from the higher management entity and maintains the information.

2) The MIH of the old access point exchanges the MIH of the new access point with Inter_MIH.query and Inter_MIH.response to determine the temporary address change of the mobile station. In addition, this message exchange serves to notify a new access point in advance that a specific mobile terminal will initiate a handover to a new access point, so that the new access point requests the previous access point for additional information necessary for handover of this specific terminal. Obtain by

3) The MIH of the previous access point sends IP_Information.request to the MIH of the new access point and requests access router address information or foreign agent address information of the new access point. The previous access point transmits IP_Information.request directly to the access router or the external agent when the mobile terminal knows an access router or foreign agent to access by handover.

4) After the MIH of the new access point receives IP_Information.request, it sends IP_CoA.request to the MIH of its access router or FA. This procedure is omitted if the MIH of the previous access point sends IP_Information.request to the MIH of the direct access router or FA.

5) The MIH of the access router or FA sends IP_CoA.indication to its upper layer. This primitive has the same form as IP_Information.request or IP_CoA.request when IP_Information., Request or IP_CoA.request is transparently delivered to higher layers.

6) The upper layer of the access router or FA responds with IP_CoA.response containing address information or 'Agent Advertisement Message / Router Advertisement' message.

7) The MIH of the access router or FA responds with IP_CoA.confirm containing address information or 'Agent Advertisement' / 'Router Advertisement' message to the MIH of the new access point.

8) The MIH of the new access point responds with IP_Information.confirm to the MIH of the previous access point, including the IP address information.

9) MIH of previous access point triggers New_IP_Address.indication including IP address information to MIH or higher layer of mobile station.

10) The second layer L2 link with the new connection point is established.

11) -12) The new link of the mobile terminal triggers Link_Up to the upper layer including the parent management object and also triggers Remote Link_Up to the MIH of the new access point. In this case, when the new access point recognizes itself that a new connection is established through its MAC layer, the MAC layer of the new access point may trigger this directly to the MIH.

13) The upper layer of the mobile terminal transmits a registration request message to the home agent.

14) The home agent responds with a 'Registration Response' to the upper layer of the mobile terminal.

10 is a flow chart of another preferred embodiment of the present invention, when a mobile terminal uses MIPv4 or MIPv6 as a mobility support protocol, and uses FA-CoA or stateless address information as a temporary address, when handing over to a new access point. When an FA-CoA or a stateless address for a new access point is allocated from a previous access point, an embodiment in which a MAC address for a new access point is not obtained by an information service is shown.

(1) The previous link of the mobile station transmits Link_Going_Down to the upper layer including the upper management object through the MIH, and also transmits the Remote Link_Going_Down to the previous access point through the MIH.

(2) The mobile terminal executes a scanning process to search for available links.

(3) When a new link is found as a result of scanning, Link_Available is triggered to the upper layer including the upper management object through the MIH.

(4) The new link layer of the mobile station goes through the MAC configuration procedure to obtain the MAC address for the new access point.

(5)-(6) The new link layer of the mobile terminal triggers Link_Going_Up to its parent management object and triggers Remote_Link_Going_Up by including the MAC address of the new access point in the MIH of the previous access point. In this case, the MIH of the mobile terminal may trigger (deliver) the IP_Information.Request to the previous access point instead of Remote_Link_Going_Up.

(7) The MIH of the previous access point detects the temporary address change of the mobile station through the MIH of the new access point and Inter_MIH.query and Inter_MIH.response. In addition, this message exchange serves to notify a new access point in advance that a specific mobile terminal will initiate a handover to a new access point, so that the new access point requests the previous access point for additional information necessary for handover of this specific terminal. Obtain by

(8) MIH of previous access point sends IP_Information.request to MIH of new access point and requests access router address information or foreign agent (FA) address information of new access point. If the previous access point knows the access router or foreign agent to which the mobile terminal performs handover and accesses, the IP_Information.request is transmitted directly to the access router or the external agent.

(9) After the MIH of the new access point receives IP_Information.request, it sends IP_CoA.indication to the MIH of its access router or FA. This procedure may be omitted when the MIH of the previous access point sends IP_Information.request to the MIH of the direct access router or FA.

(10) MIH of access router or FA sends IP_CoA.indication to its upper layer. This primitive has the same form as IP_Information.request or IP_CoA.request when IP_Information.request or IP_CoA.request is transparently delivered to higher layers.

(11) The upper layer of the access router or FA responds with IP_CoA.response containing address information or 'Agent Advertisement' message / 'Router Advertisement' message.

(12) MIH of access router or FA responds with IP_CoA.confirm containing address information or 'Agent Advertisement' / 'Router Advertisement' message to MIH of new access point.

(13) The MIH of the new access point responds with IP_Information.confirm to the MIH of the previous access point, including the IP address information.

(14) The MIH of the previous access point triggers New_IP_Address.indication including IP address information to the MIH or higher layer of the mobile station.

(15) An L2 link with a new connection point is established.

(16)-(17) The new link of the mobile terminal triggers Link_Up to the upper layer including the upper management object, and also triggers Remote Link_Up to the MIH of the new access point.

(18) The upper layer of the mobile terminal transmits a Registration Request registration message to the home agent.

(19) The home agent responds with a Registration Response.

11 is a flow chart of a preferred embodiment of the present invention, when a mobile terminal uses MIPv4 or MIPv6 as a mobility support protocol and uses FA-CoA or stateless address information as a temporary address, when handing over to a new access point. This is the case where FA-CoA or stateless address for new access point is assigned from previous access point.

In the embodiment shown in Fig. 11, in a new external agent or a new access router 5 in which a specific mobile terminal has been informed to handover, the new external agent is 'Agent Advertisement' and the new access router is 'Router Advertisement'. Is an embodiment in which a transmission (7) to a mobile terminal is performed by tunneling (6) through a previous external agent or a previous access router. At this time, the previous external agent or the previous access router de-tunnels it and provides it to the mobile station. In the case of procedure (7), 'Proxy Agent / Router Advertisement' is not a previous external agent or a former access router to relay its received agent, but to transmit its 'Agent Advertisement' or 'Router Advertisement'. It is called 'Proxy Agent / Router Advertisement'. The procedure other than this is similar to that described in the embodiment of FIG.

12 is a flow chart of another preferred embodiment of the present invention, when a mobile terminal uses MIPv4 or MIPv6 as a mobility support protocol and uses FA-CoA or stateless address information as a temporary address, when handing over to a new access point. As an embodiment of receiving a FA-CoA or a stateless address for a new access point from a previous access point, the previous foreign agent or the previous access router receives and maintains information of neighboring external agents or access routers (1), ( 2). Information can be maintained periodically on its own or on demand on a periodic basis. The procedures (3), (4) and (5) are similar to (1) and (2) of FIG. 9, and the MIH of the mobile terminal may trigger (deliver) IP_Information.Request instead of Remote_Link_Goind_Down to the previous access point. The MIH of the previous access point sends IP_Information.request to the MIH of the previous external agent or the previous access router and requests access router address information or foreign agent address information of the new access point to which a specific terminal is to be moved and connected. (6). The corresponding primitive is delivered from the MIH to the upper layer. In this case, the received primitive may be delivered transparently or may be modified in some way (7). If there is an access router address information or a foreign agent address information of a new access point requested in the information list maintained by the previous external agent or the previous access router, it is transmitted to the mobile station (8). The procedure other than this is similar to that described through the embodiment of FIG.

13 is a flow chart of a preferred embodiment of the present invention, when a mobile terminal uses MIPv4 or MIPv6 as a mobility support protocol, and uses FA-CoA or stateless address information as a temporary address, when handing over to a new access point. In the case of receiving an FA-CoA or a stateless address for a new access point from a previous access point, the external agent or access router address information of the new access point of the new access point received by the MIH of the previous external agent or the previous access router is externally transferred. It sends a primitive requesting transmission to the upper layer of the agent or the previous access router (8), and the higher layer receiving the transmission transmits the received information to the mobile terminal (9). If the mobile terminal maintains the connection with the previous link without being disconnected yet, it transmits a 'Registration Request' for registration with the home agent through the previous link (10). The registration request message sent to the home agent is relayed and delivered through a new external agent. The home agent sends a response message to the new foreign agent to approve the registration of the mobile terminal. After receiving it, the new foreign agent does not immediately transfer it to the mobile station but maintains it until it receives Link_up from the access point (11). The mobile station performs a new link establishment procedure and is notified when the link is established (13) and notifies the new connection point (Remote) (14). If the new access point manages the link status with the mobile terminal, it can know for itself. In this case, the procedure for notifying the link setting to the 'Remote' can be omitted. When Link Up is delivered to the MIH of the new access point and the upper layer, the identifier of the mobile terminal that indicates which mobile terminal has been linked up is transmitted. The MIH of the new access point informs the new foreign agent or access router that the mobile terminal's link has been established (15). Since the new external agent or access router has been informed that the link establishment of a specific mobile terminal is completed, the mobile terminal sends a 'Registration Reply' indicating that the registration procedure sent to the home agent through the previous link was successful (16). ). The 'Registration Reply' is received from the home agent, and the external agent or access router does not process it and transmits it to the mobile terminal with notification that the link is up. The rest of the procedure is similar to that described through the embodiment of FIG.

14 is a flow chart of another preferred embodiment of the present invention, when a mobile terminal uses MIPv4 or MIPv6 as a mobility support protocol, and uses FA-CoA or stateless address information as a temporary address, when handing over to a new access point. When an FA-CoA or a stateless address is allocated to a new access point from a previous access point. If the address information cannot be transmitted to the mobile terminal because the link with the previous access point is broken, the link with the new access point is performed. As soon as 10 is set, the new access point transmits the received address information (Agent Advertisement, or Router Advertisement) (11). In this case, the link establishment information may directly notify its MIH when the link layer of the new access point recognizes the new connection by itself. The remaining part is similar to the part described in FIG.

15 is a flow chart of another preferred embodiment of the present invention, when a mobile terminal uses MIPv4 or MIPv6 as a mobility support protocol and uses FA-CoA or stateless address information as a temporary address, when handing over to a new access point. When an FA-CoA or a stateless address is allocated to a new access point from a previous access point. If the address information cannot be transmitted to the mobile terminal because the link with the previous access point is broken, the link with the new access point is performed. (10) The new access point notifies the new external agent or access router of the establishment (11), and (12) As soon as the new external agent or access router establishes a link with the new access point of the mobile terminal, the new external agent or access router receives the address information. Or Router Advertisement) (13). The remaining part is similar to the part described with reference to FIG.

FIG. 16 is a flowchart illustrating another preferred embodiment of the present invention in the case of using FMIPv6 (when transmitting a link going down, knowing a PoA address of another type of interface to be handed over already).

(1) It discovers that the state of the currently connected link will be down and sends a Link Going Down trigger to the MIH and the higher layer that needs this information.

(2) It also transmits information that the link will be down to the MIH layer of the currently connected PoA. The information transmission may be performed using two layers using a link that is currently connected, or may be transmitted using three or more layers. The information transmits an address of a new point of attachment. The address of the new access point may be obtained in advance through the information service or may be obtained through neighbor broadcasting. In addition, the MIH instructs the lower link layers in advance to periodically scan to obtain information on the available link layers, and receives a list of candidate link layers from the parent management entity to maintain the information. There is.

(3) The MIH of the currently connected connection point exchanges information with the MIH of the new connection point (Inter MIH Query & Response) using the address of the new connection point sent to Link Going Down to grasp the network status information of the new connection point. In this case, the MIH of the mobile station may transmit IP_Information.Request to the current access point instead of Link Going Down (no need to change the IP address). The new network status information is a type of mobility management protocol used at an access point to which a mobile terminal newly accesses, and in the case of the same mobility management protocol, information according to the mobility management protocol, for example, In case of MIPv4, whether the FA is the same as the FA of the current access point, and in the case of the mobile IPv6 and FMIPv6, the access router connected to the current access point and the access router of the new access point are acquired. At this time, information about the access router connected to the new access point may be obtained. In addition, this message exchange serves to notify a new access point in advance that a specific mobile terminal will initiate a handover to a new access point, so that the new access point requests the previous access point for additional information necessary for handover of this specific terminal. Obtain by

(4) Inform the access router of the current access point by using the IP Information Request to inform that the particular mobile terminal will move to the access router associated with the new access point. This has the same effect as a mobile station transmitting a RtSolPr (Router Solicitation Proxy) in FMIPv6. However, since the mobile terminal detects whether the mobile terminal moves and triggers the network rather than transmitting the RtSolPr, the mobile terminal can omit the message sending the RtSolPr.

(5) The currently connected access router sends PrRtrAdv (Proxy Router Advertisement) for the access router of the new access point by a trigger sent from the MIH. This allows the PrRtrAdv to be transmitted more quickly than the RtSolPr of the mobile terminal.

(6) The multi-mode mobile station constructs a new 'Care of Address' (NCoA) that can be used by the new access router connected to the new access point through the received PrRtrAdv.

(7), (8), (9), (10), (11) The multi-mode mobile terminal and the access router perform the procedure for FMIPv6.

(12) A link having two layers or less with a new link is set.

(13) It transmits to the upper layer through the MIH that the establishment of the new link is completed and the L3 packet can be sent. When this trigger is delivered, the mobility management entity sends FNA (Fast Neighbor Advertisemnt) quickly. Upon receiving this, the new access router transmits the received packet to the mobile station.

(14) At the same time as (13), the MIH of the previous connection point is informed that the link with the new connection point has been established.

(15) The MIH of the access router triggers data forwarding to the access router connected to the new access point, knowing that the setting with the new access point is completed. This allows you to know exactly when your previous access router will forward data. The effect of the present invention is that the MIH of the previous access point and the MIH of the access router know the exact time point by mutual communication, and the MIH of the access router indicates the forwarding of data, and the exact time point may be different from that shown in this embodiment. .

(16) Data is transferred from the old access router of the old access point to the new access router of the new access point.

(17) The fact that a new link is established means that a remote trigger is sent to the MIH of the connection point of the new link. This procedure takes place at a point similar to the procedure of (13) above. At this time, when the link layer of the new access point recognizes a new connection setting by itself, it may directly inform the MIH thereof.

(18) The MIH of the new access point indicates that the link of the new terminal can be established and transmit data by communicating with the MIH of the access router connected to the new access point.

(19) Informs you that the previous link has been released. This procedure may be done by the command of MIH after the establishment of new link is completed, and it may occur immediately after the establishment of new link, but it may be maintained for a certain time for redundancy with new link.

(20) The access router of the new access point triggered by the procedure of (18) quickly transmits data to the multi-mode mobile terminal without delay.

FIG. 17 is a flowchart illustrating another preferred embodiment of the present invention, in which FMIPv6 is used (when obtaining a PoA address of another type of interface to be handed over when transmitting Link Going Up).

In the case of using FMIPv6, the embodiment of FIG. 17 is different from the case of knowing the PoA address of another type of interface to be handed over when transmitting Link Going Down. This is the case where the address of the new access point (PoA) is known while the link establishment procedure with the client is in progress (5). Notify the MIH of the previous access point that the link will be established remotely (7). The procedure below is similar to that of the embodiment described in the embodiment of FIG.

Fig. 18 is a flow chart of a still further preferred embodiment of the present invention, which relates to an embodiment in which a link with a previous access point is released before establishing a link with a new access point when using FMIPv6.

In the embodiment of FIG. 18, when the FMIPv6 is used, a procedure similar to the embodiment shown in FIG. 16 is performed after the procedure with the new access router (1) to (11). It is the case of (12) when it is released for reasons such as movement. When the connection with the previous link is released, the MIH of the mobile station is informed of this from the lower link layer (13). When the previous access point manages the connection with the mobile station, it knows that the connection with the mobile station has been released and notifies the previous access router that the connection of the specific mobile station is lost (14). The information transmitted to identify a specific terminal is the IP address or link layer address (eg MAC address) or ESN (Electronic Serial Number) number used by the mobile station at the previous access point. It is included in the Remote Link Down that informs the router. Upon receiving this, the access router delivers a packet of a specific terminal which has been disconnected through a previously established tunnel (15). The procedure other than this is similar to the procedure described in FIG.

19 is a flow chart of another preferred embodiment of the present invention. In case of using FMIPv6, when a link with a new access point is established, a packet transmitted quickly at a new access point is transmitted after a link is established by a trigger transmitted from the MIH to a higher layer. It is about receiving.

19 illustrates a procedure similar to the embodiment of FIG. 16 when using FMIPv6, and then performs a procedure with a new access router (1) to (11), and then establishes a procedure with a new link (12). ). When the link establishment with the new access point is completed, the MIH is notified that the new link is established from the link layer of the mobile station and is transmitted to the upper layer including the mobility management entity (13). The mobility management entity, which has received the information that the new link is established, immediately transmits a 'Fast Neighbor Advertisement' to the new access router (17). The access router, which has received this, transmits the received packet to the terminal (18). The procedures 14 to 16 in the case where the link setting with the previous connection point are still maintained are the same as the procedures 14 to 16 in FIG.

FIG. 20 is a flow chart of a still further preferred embodiment of the present invention, in the case where FMIPv6 is used, when a link with a previous access point is released before establishing a link with a new connection point. The present invention relates to an embodiment in which a packet transmitted quickly at a new access point is transmitted after a link is established by a trigger transmitted from a MIH to a higher layer.

The embodiment of FIG. 20 generates a new CoA by performing a procedure with a new access router using a procedure similar to the embodiment of FIG. 16 when using FMIPv6 (1) to (6). Thereafter, the link with the previous access point was released for some reason (7). The release of the link is notified to the upper layer through the MIH from the link layer of the mobile terminal (8). The mobile terminal initiates a link establishment procedure with a new connection point and establishes a link (9). When the link establishment is completed, the link establishment completion is notified from the new link layer of the mobile terminal to the upper layer including the mobility management entity (10). The mobility management entity notified of this promptly sends a Fast Neighbor Advertisement (Fast Binding Update) so that the new access router can establish a tunnel with the previous access router to receive the data it was receiving. 12)-(13). After the configuration of the tunnel is completed, the previous access router transmits the packet to the new access (14), and the new access router forwards it to the mobile terminal (15).

FIG. 21 is a flow chart of another preferred embodiment of the present invention, when a mobile terminal uses MIPv4 or MIPv6 as a mobility support protocol and uses FA-CoA or stateless address information as a temporary address, handover to a new access point. Before attempting, the embodiment obtains information from the previous access point that the IP address to be used at the new access point is available without change to the current IP address.

In the embodiment of Fig. 21, the mobile terminal triggers the Remote Link_Going_Up to the new access point to the old access point (6), so that the old access point forwards the IP_Information.request asking the new access point for the IP information that the mobile terminal can use at the new access point ( 7). IP_Information.request includes IP address information used by the mobile station at the previous access point. The new access point compares the information contained in the IP_Information.request with the IP address (including the temporary IP address) that the mobile terminal can use for handover, and if the old address is available, the IP address change message appears in the IP_Information.Confirm message. Respond to the previous access point by setting the notification 'field to 1 (no IP address change required) (8). The previous access point receives this IP_Information.confirm and forwards it to the mobile station (9). In the present embodiment, a new access point is generated and delivered a response (IP_Information.confirm) in response to IP_Information.request, but this information is received by listening to an advertisement of a router or foreign agent connected to the new access point. If there is no address information available, IP_Information.request is forwarded to the access router or external agent and the access router or external agent forwards IP_Information.confirm to the new access point in response to the new access point. You can also pass it.

Fig. 22 is a flow chart of another preferred embodiment of the present invention, when a mobile terminal uses MIPv4 or MIPv6 as a mobility support protocol and uses FA-CoA or stateless address information as a temporary address, when handovers to a new access point. In the case of receiving a FA-CoA or a stateless address for a new connection point from the previous connection point, it is similar to the procedure of FIG. It sends an IP_Information.Request requesting the IP address information (7). When a new access point receives this and compares the information contained in IP_Information.request with the IP address (including temporary IP address) that the mobile terminal can use for handover, the old address cannot be used and the new IP address must be changed. In operation 12-13, IP_Information.Confirm including IP address information is transmitted to the mobile station through the previous access point. In this embodiment, IP_CoA.request (or requesting IP-related information from the access router or foreign agent connected to the new access point because the new access point does not have enough information to respond to IP_Information.request (or The same effect can be achieved by sending IP_information.request.), And the mobile terminal acquires the information and the mobile terminal includes this information in IP_Information.confirm, but the new access point sends the advertisement of the access router or the external agent. If you listen and have enough information about IP, you can send it directly to the mobile station.

Fig. 23 is a flow chart of another preferred embodiment of the present invention, when a mobile terminal uses MIPv4 or MIPv6 as a mobility support protocol and uses FA-CoA or stateless address information as a temporary address, handover to a new access point. Before attempting, the mobile terminal transmits the IP address information request to the new access point through the old access point to obtain information that the IP address information does not change.

In the embodiment of Fig. 23, the mobile terminal transmits IP_Information.Request to the new access point through the previous access point (6-7). If a new access point can use the old address compared to the information contained in the IP_Information.request and the IP address (including the temporary IP address) that the mobile terminal can use for handover, the IP_Information.Confirm message will indicate the 'IP Address Change'. Respond to the previous access point by setting the notification 'field to 1 (no IP address change required) (8). The previous access point receives this IP_Information.confirm message and delivers it to the mobile station (9). In the present embodiment, a new access point is generated and delivered a response (IP_Information.confirm) in response to IP_Information.request, but this information is received by listening to an advertisement of a router or foreign agent connected to the new access point. If no IP address information is available, IP_Information.request is forwarded to the access router or external agent, and the access router or external agent forwards IP_Information.confirm to the new access point in response to moving the new access point. It may be delivered to the terminal.

Fig. 24 is a flow chart of another preferred embodiment of the present invention, in case of using FMIPv6 (knowing PoA address of another kind of interface to be handed over during the transmission of Link Going Down), it can be used at the new access point from the previous access point. According to an embodiment of the present disclosure, information on availability of an existing IP address without change is obtained by referring to the address information.

In the embodiment of Fig. 24, the mobile terminal triggers Remote_Link_Going_Down to the previous access point (2), and the previous access point sends an IP_Information.Request to the previous access router asking for the IP information that the mobile terminal can use at the new access point (3). The old access router sends IP_No_Change to its MIH when the mobile terminal can hand over and use the new IP address without changing the existing IP address (4). The MIH of the access router sets the 'IP Address Change notification' field to 1 (no IP address change) in the IP_Information.Confirm message and transmits it to the previous access point (5), and the previous access point forwards it to the mobile station (6).

FIG. 25 is a flow chart of another preferred embodiment of the present invention, similar to the procedure of FIG. 16, except that the mobile terminal requests IP information that can be used at the new access point instead of triggering Remote_Link_Going_Down to the previous access point. (2). The previous access point receives it and forwards it to the previous access router (3). The previous access router sends a proxy advertisement message for the new access router to the mobile station by referring to the address of the new access router included in the request message (4).

FIG. 26 is a flowchart of another preferred embodiment of the present invention, similar to the procedure of FIG. 24, but the mobile terminal transmits IP_Information.Request instead of triggering (delivering) Remote_Link_Going_Down to the previous access point (2).

FIG. 27 is a flow chart of another preferred embodiment of the present invention, similar to the procedure of FIG. 16, but with the old access router communicating with the new access router through a new access point to obtain IP address information of the multi-mode mobile terminal and remote link up. Shows the case of data forwarding from the old access router to the new access router.

It discovers that the state of the currently connected link will be down and sends a Link Going Down trigger to the MIH and the higher layer that needs this information (1). The MIH layer of the currently connected PoA also transmits information that the link will be down. The information transmission may be performed using two layers using a link that is currently connected, or may be transmitted using three or more layers. The information transmits an address of a new point of attachment. The address of the new access point may be obtained in advance through the information service or may be obtained through neighbor broadcasting. In addition, the MIH instructs the lower link layers in advance to periodically scan to obtain information on the available link layers, and receives a list of candidate link layers from the parent management entity to maintain the information. (2) The MIH of the currently connected connection point exchanges information with the MIH of the new connection point (Inter MIH Query & Response) using the address of the new connection point sent to Link Going Down to grasp the network status information of the new connection point. (3).

The MIH of the previous access point requests the new access router through the MIH of the new access point to request IP address information for the mobile terminal to use after handover. In addition, this message exchange serves to notify a new access point in advance that a specific mobile terminal will initiate a handover to a new access point, so that the new access point requests the previous access point for additional information necessary for handover of this specific terminal. (4)-(7). The IP information response informs the previous access router of the address information (8). The currently connected access router receives information about the access router of the new access point by a trigger sent from the MIH and transmits PrRtrAdv (Proxy Router Advertisement) containing the information to the mobile terminal (9). The multi-mode mobile station configures a new 'Care of Address' (NCoA) that can be used in the new access router connected to the new access point through the received PrRtrAdv (10). The multi-mode mobile terminal and the access router perform procedures for FMIPv6 (11) (12) (13) (14) (15). A link of two layers or less with a new link is set (16).

It notifies the MIH of the new access point and the new access router through the remote link up as well as the setting of the new link, notifying that the mobile station has handed over to the new access router (17)-(19). The MIH of the new access router that has received the remote link up trigger indicates data forwarding from the previous access router by sending Start_Data_Forward to the previous access router. If data transfer is performed between two access points, the MIH of the new access point may transmit Start_Data_Forward to the MIH of the previous access point to indicate data forwarding in the same manner (20). Packets are forwarded from the old access router to the new access router (21), indicating that the previous link has been released. This procedure may be performed by the command of the MIH after the establishment of the new link is completed, and may occur immediately after the establishment of the new link, but may be maintained for a certain time for redundancy with the new link (22). Since the access router of the new access point knows that the link with the new access point is completed, the access router quickly transmits the data to the multi-mode mobile terminal without delay (23).

28 shows a MIH level handover scenario using the commands presented in the present invention as a procedure flow diagram of yet another preferred embodiment of the present invention.

The previous link of the mobile station detects that the state of the currently connected link will be down and sends a Link Going Down.indication trigger to the MIH and the higher layer that needs this information (1). The upper layer instructs MIH to enable link scan through the MIH_Scan command (2). A new link that can be handed over announces that its link can be handed over via Link_Available (3). The MIH of the mobile station sends an intention to handover to a potentially handoverable link by scanning MIH_Handover_Initiate.request to the MIH of the previous access point (4). The MIH of the previous access point queries the MIH of the new access point via Inter_MIH.query whether the resources of the new link are sufficient, and informs that the mobile station will handover to the access point (5). The MIH of the new access point informs the result of the request through Inter_MIH.query through Inter_MIH.response (6). The previous access point informs the access point that can be handed over based on the information obtained by Inter_MIH.query / response. In this case, according to the situation of link resource allocation or the like, the previous access point may select and inform a link different from the link requested by the mobile terminal (7). The mobile station sends IP_information.request to the MIH of the new access point in order to obtain IP address information for the selected link in advance. Alternatively, the MIH of the previous access point that obtained the selected link through Inter_MIH.response may request IP address of the mobile station by sending IP_informaiton.request directly to the MIH of the new access point (7). The MIH of the access point is obtained by requesting a new IP address of the mobile station from the connected access router (8)-(12). The MIH of the new access point transmits the acquired IP address to the mobile terminal through IP_information.response (13). The mobile station informs the handover start by sending MIH_Handover_Commit.request to the MIH of the previous access point (14). The previous access point sends MIH_Handover_Commit.resonse to the mobile terminal in response (15). The new link of the mobile station transmits Link_Up to the higher layer and remotely transmits to the MIH of the new access point, thereby informing the mobile terminal of the successful establishment of the new link (16). The MIH of the new access point sends Start_Data_Forward to the old access router, requesting data forwarding from the old access point to the new access point so that packets from the old access router are forwarded to the new access router (17, 18). The data transfer request may be made by requesting a new access point to a new access router and a new access router to the old access router. In addition, when data transfer is performed between access points, a new access point may be requested by passing Start_Data_Forward to the previous access point and data may be transmitted without requesting the access router.

FIG. 29 is a flowchart illustrating still another preferred embodiment of the present invention, in which an IP address is pre-configured using a method of pre-configuration of an IP address to be used after handover from an information server presented in the present invention. One embodiment showing setting.

The previous link of the mobile station acquires information that the state of the currently connected link will be down, and sends a Link Going Down.indication trigger to the MIH and the higher layer that needs the information. In addition, the information is transmitted to the previous access point, which includes the address (MAC address or IP address) of the new access point to be transmitted (1). The link of the mobile terminal will be down and the previous access point knowing the address of the access point to which the mobile terminal will move requests the information server for information related to the IP address setting that the mobile terminal can use at the new access point (2). The information server forwards the information related to the IP address setting to the requesting access point (3). Information related to the IP address is relayed to the mobile terminal and delivered to the upper layer of the mobile terminal (3).

Another method of receiving IP address setting information through an information server is a method in which a MIH of a mobile terminal directly requests and receives information from an information server. The mobile terminal requests information related to the IP address from the information server (4). The information server delivers information related to an IP address that can be used in a new access point after the handover requested by the mobile terminal, and the information is transmitted to the upper layer of the mobile terminal (5). The upper layer of the mobile terminal, that is, the layer related to the IP address setting, for example, the IP layer or the mobility protocol management layer is configured to set the IP address before handover, 'Router Solicitation' for IPv6, and ' Send Agent Solicitation '. The 'Router Solicitation' or 'Agent Solicitation' is unicast to the Access Router or Foreign Agent to be used at the new access point or tunneled through the access router or external agent of the current access point. tunneling) (6). The access router or the external agent receiving the 'Router Solicitation' or the 'Agent Solicitation' of the mobile station sends a response to the mobile station through the unicast or tunneling method (7). The mobile station presets an IP address with the information received before the handover (8). The mobile terminal establishes a link with the new connection point (9). It is known that the new link is established to the upper layer through the MIH of the mobile terminal (10). The upper layer performs a registration procedure with a home agent since a new link is established and can transmit an IP layer packet (11, 12).

Another method of pre-selection of IP address is that the mobile terminal obtains the DHCP server address of the new access point through the information server and is assigned an IP address to be used at the new access point by communicating with the DHCP server through the old access point before handover by the mobile terminal. will be.

It will be apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. Accordingly, the above detailed description should not be construed as limiting in all aspects and should be considered as illustrative. The scope of the invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

According to the IP address resetting method when performing handover between heterogeneous networks according to the present invention, a message transmitted unnecessarily by allowing the third layer L3 to grasp the second layer L2 handover through MIH communication There is an effect that can reduce the time required for handover.

Claims (4)

In the method for communicating information for a mobile terminal of a wireless mobile communication network, Transmitting, by the mobile terminal, first information to a first point of attachment (PoA); In order for the first access point to obtain information about the second access point and the information about the second access router, and supply the information required for the handover of the mobile terminal according to the reception of the first information to the second access point, Exchanging second information with the second access point using the address of the second access point; Informing the second access point that the mobile terminal initiates handover to the second access point through the exchange of the second information; Notifying the first access router that the mobile station moves to the second access router using the IP information request for the second access router; Sending, by the first access router, IP information confirmation according to the IP information request to the first access point; Sending, by the first access router, a proxy router advertisement for the second access router to the mobile terminal according to the notification by the first access point; Setting, by the mobile terminal, a new address of the mobile terminal using the proxy router advertisement; While the mobile terminal maintains a connection with the first access point, the mobile terminal establishes a new connection with the second access point at a link layer of the mobile terminal using the proxy router advertisement. ; The mobile terminal notifying the first connection point that the new connection is established between the mobile terminal and the second connection point; Triggering the first access router such that the first access point forwards data to the second access router according to the notification by the mobile terminal; Forwarding the data by the first access router to the second access router while the mobile terminal maintains a connection with the first access point; And Transmitting, by the second access router, the data to the mobile terminal; The new address of the mobile terminal is used by the second access router, The first access point has wireless access to the mobile terminal and is connected to the first access router, The first information includes a second access point obtained before the first information is transmitted to the first access point, and indicates that the connection between the mobile terminal and the first access point is going to be down. The information about the second access point includes the type of mobility management protocol used by the second access point, After the second information is exchanged, the second access router is connected with the second access point, The IP information check includes a bitmap field according to the mobility management protocol support type, a field indicating whether a current address needs to be changed when the mobile station moves to the second access point, and an agent advertisement. Or a time stamp field indicating a time difference when a router advertisement is received and stored and when encapsulated for transmission, The mobile terminal, the first access point, the second access point, the first access router and the second access router are different entities, The mobile terminal, the first access router, the second access router, the first access point and the second access point each include a medium independent handover management module. The first access point and the second access point each include a broadband wireless access network base station, a wireless local area network access point, or a cellular system base station, The mobile terminal uses Fast Handovers for Mobile Internet Protocol version 6 (FMIPv6). delete The method of claim 1, The mobile terminal further comprises the step of informing the upper layer of the mobile terminal that the establishment of the new connection is completed through the link layer, And the link layer is hierarchically higher than the layer in which the handover management module is implemented in the mobile terminal. The method of claim 3, wherein Informing the second access router that the second access point may transmit data by establishing the new connection; And Informing the upper layer of the mobile terminal that the mobile terminal has released its connection with the first access point through the link layer.

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