Abstract: A technology is disclosed that provides a handover method and the like capable of improving communication efficiency by reducing tunnel overhead between a mobile node and a home agent. The technology includes: a step of transmitting, by a mobile node (UE) 107, a message including a home address allocation request in a network 102 of the handover destination and an allocated first address, to a home agent (HA) via an access router 104 before a handover; and a step of performing, by the HA, a predetermined process based on the received message and transmitting to the UE, a response message including a home address in response to the allocation request.

Abstract: The invention relates to a method for informing two access gateways about each other's presence and identity, in order to establish a data path between them, thereby shortening the overall data path of data packets exchanged between two mobile nodes (MN), that are located in different networks. In particular, each access gateway is provided with the other gateway's address and additionally with the other MN's address for forwarding by the access gateway those data packets destined to the other MN to the other access gateway. A combination of Session Initiation Protocol messages (Invite and Ringing) and route optimization messages are used, so as to confer the information on the gateway's ID and MN's address to the gateways.

Abstract: Disclosed is a technique to enable a session handover between devices with different key generation functions in an authentication protocol. According to the technique, when a session where a UE (200) receives contents from a contents server (700) is to be handed over to a target node (300), the UE firstly transfers information (session HO information) necessary to the session handover to the target node (Step S1001). The target node performs authentication processing with an authentication server (600) of the network to which the UE is connected and notifies the authentication server of the session HO information transferred from the UE (Step S1003). The authentication server performs authentication for the session handover based on the session HO information, and when the authentication succeeds, the session is handed over from the contents server to the target node, and the contents are distributed to the target node (Step S1005).

Abstract: The current invention relates to a method for a network attachment procedure and a user equipment in a wireless mobile network, the wireless mobile network comprising a user equipment with a temporary identity and at least one mobility management entity. The method comprises the steps of providing an estimation whether the user equipment is unknown at the mobility management entity and sending the user equipment's temporary identity during the network attachment procedure. If the user equipment has been estimated to be unknown at the at least one mobility management entity, the user equipment's identity is sent during the network attachment procedure. These steps are carried out by the user equipment.

Abstract: A router, if judging that a routing function is impossible to execute, sends out a connection instruction message including the address of a terminal on a local network terminating the relaying flow, to another router to solicit switching. The router having received the connection instruction message starts a process for connecting with an external network while executing a process for link connection with a terminal, and then sends out a connection completion notice message when the connection with both the external network and the terminal is established. This process enables the router to switch a path rapidly.

Abstract: Provided is a technique to provide a handover processing method that allows a mobile terminal to be handed over seamlessly while preventing occurrence of double reservation. The method includes a step where a mobile terminal (100) decides to connect to a desired access network (113) and detects the possibility of occurrence of a network-initiated handover processing performed by a predetermined device of the communication network as one of the controlling entities, and a step where the mobile terminal transmits a connection request message requesting a connection to the desired access network, the connection request message including information to maintain the connection with the access network with which the mobile terminal is currently connecting, to a base station disposed in the desired access network based on a detection result of the detection step.

Abstract: Disclosed is a technique to provide a handover processing method to avoid a failure in both of the handovers and enables communication via an access network as a UE initiated handover target that is originally optimal. The handover processing method includes: a step where a mobile terminal (100) connected with a first access network (111) transmits a connection establishment request message requesting a connection with desired a second access network (113) to a base station (107) placed in a second access network; a step where the mobile terminal determines whether a predetermined event occurs or not; a step where, when the mobile terminal determines that the predetermined even occurs, generates a reconnection request message including first flag information to the second access network; and a step where the mobile terminal transmits the generated reconnection request message to the base station in the second access network.

Abstract: A router, if judging that a routing function is impossible to execute, sends out a connection instruction message including the address of a terminal on a local network terminating the relaying flow, to another router to solicit switching. The router having received the connection instruction message starts a process for connecting with an external network while executing a process for link connection with a terminal, and then sends out a connection completion notice message when the connection with both the external network and the terminal is established. This process enables the router to switch a path rapidly.

Abstract: The invention relates to a method for discovering a home agent serving a mobile node upon the mobile node changing its mobility management scheme in a packet-switched network and the implementation of such method in a mobile node or home agent. In order to propose a home agent discover scheme that maintains session continuity in a seamless manner upon a mobile node changing its mobility management scheme, a mobile node comprises information on its location prior to changing the mobility management scheme to one of the first signaling messages transmitted upon changing the mobility management scheme (home agent discovery message). The receiving node uses this information to identify the home agent serving the mobile node or to provide a hint to the home agent where the mobile node is registered in a response message to the mobile node. This approach may also be used for path optimization when a mobile node moves from a trusted to an un-trusted access network.

Abstract: Disclosed is a technique to enable a mobile terminal to grasp an address handling method used for each service and hence to achieve more efficient communication. According to this technique, a mobile terminal (UE) 15 inquires a home PMIPv6 domain 10 about a method of handling each address currently maintained by the mobile terminal (e.g., which address should be used as an MIPv6 home address (HoA)) in a state of being attached to the home PMIPv6 domain 10 before starting MIPv6 as a mobile management protocol, and acquires and stores the inquiry result in advance. Then, for example, when moving to a foreign network 20 and starting MIPv6, the stored inquiry result is referred to select an address appropriate as an HoA in order to perform a search for a HA (Home Agent) and BU (Binding Update) transmission.

Abstract: A technique is disclosed, according to which the efficiency of a communication channel where the communication is performed between radio communication terminals. According to this technique, under the network condition where different types of connection can be made to different types of networks, radio communication terminals performing communication with each other can perform communication by being connected to the same access network. For instance, by changing the connection of UE_a310a, which performs communication with UE_b310b from eNB 150 to AP b230b, the communication channel of UE_a and UE_b can be changed from a channel 350 to a channel 360. Further, by turning back the channel at PDG 210, for instance, the communication channel can be shortened.

Abstract: The invention relates to a method for a handover of a mobile node from a non-3GPP to a 3GPP network, and of a mobile node, which is located in a non-3GPP/3GPP network. The handover is improved by discovering an appropriate MME and registering the mobile node at the discovered MME, in advance. This includes to first determine the location of the mobile node in the non-3GPP network, so as to be able to detect an MME in the vicinity of the mobile node's location. The 3GPP contexts are then transmitted to the new MME before the handover is performed. Moreover, the invention teaches to change the Serving-Gateway in the 3GPP network before performing a handover, thereby accelerating the handover. When a handover gets likely, the mobile node's location is determined and a new Serving-Gateway is selected. The data path is changed to go via the new Serving-Gateway.

Abstract: The invention provides a method for trust relationship detection between a core and access network for a user equipment. The gist is that a security tunnel establishment procedure is used so one entity, be it part of the core network or be it the user equipment itself, is provided with information to determine whether the access network is trusted or untrusted. The information may comprise a first IP address/prefix, which is initially assigned to the user equipment, upon attaching to the access network. The necessary information may further comprise a second IP address/prefix, which is an address/prefix that is allocated at a trusted entity of the core network. Depending which entity determines the trust relationship of the access network, it might be necessary to transmit either the first IP address/prefix or the second IP address/prefix or the first and the second IP address/prefix using the security tunnel establishment procedure.

Abstract: When the routing function of router becomes disabled, a routing stop message is multicast to all terminals and another router in a LAN. If another router can provide the routing function, a routing start message is multicast to all terminals and the other router in the LAN. This method allows the terminals in the LAN to switch the default router at a predetermined timing according to both messages, thus minimizing the default router switching delay time and the packet loss.

Abstract: A time required for actually starting encrypted communication after a trigger of an encrypted communication is shortened. When a key exchanging process is to be applied in order to exchange key information upon encrypting a communication performed between a communication terminal 11 and a gateway device 25, a network relay device 15 relays the key information, contents of the key exchanging process are divided into a former-half process and a later-half process, and the network relay device 15 executes the former-half process substitute for the communication terminal 11 to establish “IKE SA”. Then, information obtained as the result of the former-half process is transferred from the network relay device 15 to the communication terminal 11.

Abstract: A communication terminal apparatus wherein even if there occurs a dropout or overtaking of call control messages, the current service can be continued without increasing the load of an apparatus such as a server in the network. In this apparatus, a VoIP call control part (103) performs call controls including both a call establishment of a VoIP telephone conversation using a wireless LAN system and a call disconnection thereof. A line switching call control part (104) performs call controls including both a call establishment of a line switching telephone conversation using a mobile communication (cellular) system and a call disconnection thereof. A handover part (105) determines the reception quality of the wireless LAN system and that of the mobile communication (cellular) system and controls, based on the determination results, the handover between the wireless LAN system and the mobile communication (cellular) system.

Abstract: A rear-focusing type zoom lens includes, in order from an object side, a positive first group being fixed, a negative second group moving toward an image plane along an optical axis during zooming from a wide-angle end to a telephoto end; a negative third group being fixed in an optical axis direction, and a positive fourth group moving along the optical axis direction to correct image plane variation being caused by zooming. The first group includes a first subgroup having a negative power as a whole and a second subgroup having a positive power as a whole. The first subgroup includes a negative meniscus lens having a convex surface directed toward the object side and a negative lens. The second subgroup includes a positive lens group having at least one positive lens, a negative lens, a positive lens, and another positive lens group having at least one positive lens.

Abstract: In a mobile communication system utilizing Mobile IP, information on the access network is exchanged between access routers. And when a mobile terminal performs a handover, the previously exchanged information on the neighbor access routers and the access network information are provided to the mobile terminal. By so doing, the mobile terminal can determine a destination access router in advance, enabling to realize an efficient handover processing.

Abstract: A mobile communication apparatus includes a registration request part (47) requesting a correspondent node to make location registration, a BU list memory (45) keeping a list of the correspondent nodes which have made the location registration, a handover detection part (41) detecting the start of a handover, and a registration cancellation processing part (46) canceling the location registration of the correspondent nodes in the BU list, upon notification of start of handover by the handover detection part (41), thereby reducing loss of packets transmitted from the correspondent nodes during the handover, because the route optimization applied to the correspondent nodes registered in the BU list at the start of the handover is canceled by requesting the cancellation to the correspondent nodes.

Abstract: In a mobile communication system utilizing Mobile IP, information on the access network is exchanged between access routers. And when a mobile terminal performs a handover, the previously exchanged information on the neighbor access routers and the access network information are provided to the mobile terminal. By so doing, the mobile terminal can determine a destination access router in advance, enabling to realize an efficient handover processing.