Abstract: In node management in a packet-switched network, a first node acts as a proxy for a second node. Both nodes have network-layer addresses at the network layer and link-layer addresses at the link layer. The first node receives a request to receive and forward packets addressed to the second node's network-layer address. The same network-layer address is associated with the first and the second node, and the first and the second node have distinct link-layer addresses. The first node advertises to nodes attached to the packet-switched network the first node's link-layer address as a destination address for the second node's network-layer address; the second node does not advertise. The first node receives in response to advertising, packets destined to the second node's network-layer address having the first node's link-layer address and forwards packets addressed to the second node's network-layer address to the second node using its link-layer address.

Abstract: The invention relates to a method for routing packets in a system of packet-switched networks comprising a plurality of home agents, at least one mobile node and at least one correspondent node, the mobile node having at least a first home address and communicating with the correspondent node over a first of the plurality of home agents.

Abstract: The invention relates to a method performed by a home agent serving a mobile node in a home network of the mobile node upon attachment of a mobile node to the home network as well as to the home agent. Further, the invention also relates to a method for enabling simultaneous use of a plurality of interfaces by a mobile node being attached to a home network through one of the plurality of interfaces and to at least one foreign network through at least another interface of the plurality of interfaces. Moreover, the invention provides a mobile node and a proxy acting on behalf of the mobile node. To enable a mobile node to use a home network and at least one further foreign network for communications the invention suggests the registration of the mobile node's home address or of a network node within its home network as a care-of address in the home network.

Abstract: The invention relates to a method for managing the movement of a mobile node from a first router in a first network to a second router in a second network, wherein the mobile node communicates with a corresponding node. In order to enable seamless communication between the mobile node and the corresponding node, the second router is dynamically configured by the first router to transmit a router advertisement message to the mobile node, the router advertisement message comprising a subnet prefix of an IP address of the mobile node, said subnet prefix belonging to the first network. A layer 3 link change as observed by the mobile node can be postponed and a default router of the mobile node can be changed to the new access router immediately after the layer 2 handover, thus enabling very fast handovers without requiring modifications to the mobile node implementations.

Abstract: The invention relates to a method for node management in a packet-switched network, wherein a first node acts as a proxy for a second node, both nodes having network-layer addresses and link-layer addresses, the network-layer addresses at the network layer and the link-layer addresses at the link layer being used for communication in the packet-switched network. The method comprises the following steps performed by the first node: The first node receives from the second node a request to receive and forward packets addressed to the second node's network-layer address, whereby the same network-layer address is associated with the first node and the second node, and the first node and the second node have distinct link-layer addresses. The first node advertises to nodes attached to the packet-switched network the first node's link-layer address as a destination address for the second node's network-layer address, while the second node does not advertise.

Abstract: The present invention relates to a method and computer-readable medium for loop detection in data packet communication utilizing a tunnel in a network comprising a plurality of nodes. The method comprises the steps of, when a first node transmits a data packet, encoding an identification of the first node in at least two header fields of the data packet to be transmitted, and when the first node receives a data packet, analyzing the at least two header fields of the data packet, deciding if a loop exists by determining if the data packet was sent by the first node itself, based on the analysis of the at least two header fields of the data packet.

Abstract: The invention relates to a method performed by a home agent serving a mobile node in a home network of the mobile node upon attachment of a mobile node to the home network as well as to the home agent. Further, the invention also relates to a method for enabling simultaneous use of a plurality of interfaces by a mobile node being attached to a home network through one of the plurality of interfaces and to at least one foreign network through at least another interface of the plurality of interfaces. Moreover, the invention provides a mobile node and a proxy acting on behalf of the mobile node. To enable a mobile node to use a home network and at least one further foreign network for communications the invention suggests the registration of the mobile node's home address or of a network node within its home network as a care-of address in the home network.

Abstract: The invention relates to a method for establishing by a mobile node an additional session via a connection to a packet data network in a mobile communication network and a mobile node and a packet data network gateway adapted to perform this method. In order to suggest optimized home link detection by a mobile node one aspect of the invention is to delay the decision on whether the mobile node is located on the home link or not. In conventional home link detection, the mobile node checks before sending any binding update on an access interface whether its prefix of the local IP address configured on that access interface is matching a home address prefix received during bootstrapping. According to one aspect of the invention, this home link detection is delayed in that home link detection is based on comparing a home address prefix received during bootstrapping and the advertised local prefix of a router advertisement received after bootstrapping.

Abstract: A method and a server acting as a Home Agent are provided for packet switched data transmission between a first mobile node and a correspondent mobile node in a mobile communication system comprising a plurality of mobile networks. Each of the first mobile node and the correspondent mobile node are allocated to respective home networks, and a network server is provided as a home agent to each mobile node, respectively. Then, data packets are routed from the first mobile node to the correspondent mobile node, over a first data tunnel from the first mobile node to any first one of the home agents and over a second data tunnel from said first one of the home agents to the correspondent mobile node without passing the respective other home agent.

Abstract: The invention relates to a method and mobile node capable of detecting whether or not the network to which the mobile node is attached is using a network-based mobility management function for the mobile node or not. In order to enable a mobile node to detect whether the network is using a network-based mobility function for the mobile node, upon establishment of a PDN connection or IP session, the mobile node sends a probe message to the network destined to itself and determines based on the modifications of the probe message returned to the mobile node whether the network is using a network-based mobility function for the mobile node or not.

Abstract: The invention relates to a method performed by a home agent serving a mobile node in a home network of the mobile node upon attachment of a mobile node to the home network as well as to the home agent. Further, the invention also relates to a method for enabling simultaneous use of a plurality of interfaces by a mobile node being attached to a home network through one of the plurality of interfaces and to at least one foreign network through at least another interface of the plurality of interfaces. Moreover, the invention provides a mobile node and a proxy acting on behalf of the mobile node. To enable a mobile node to use a home network and at least one further foreign network for communications the invention suggests the registration of the mobile node's home address or of a network node within its home network as a care-of address in the home network.

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: A method and apparatus for improved context transfer in heterogeneous networks is presented. Context information is collected from source entities in a first access network by a context transfer manager and transmitted to a context transfer manager of a second access network which forwards the context information to target entities therein. In one of the context transfer managers at least a part of the context information is translated from a format supported in the first access network to another format supported in the second access network. The method may be carried out proactively preceding a handover or reactively following a handover. In one embodiment, context transfer within one access domain is performed directly between access routers, whereas context transfer between different access domains is performed via the context managers. In another embodiment, beacons from access points are counted in order to determine candidates for a pending handover.

Abstract: A method and apparatus for improved context transfer in heterogeneous networks is presented. Context information is collected from source entities in a first access network by a context transfer manager and transmitted to a context transfer manager of a second access network which forwards the context information to target entities therein, in one of the context transfer managers at least a part of the context information is translated from a format supported in the first access network to another format supported in the second access network. The method may be carried out proactively preceding a handover or reactively following a handover. In one embodiment, context transfer within one access domain is performed directly between access routers, whereas context transfer between different access domains is performed via the context managers. In another embodiment, beacons from access points are counted in order to determine candidates for a pending handover.

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: 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: A first aspect of the invention relates to a method for verifying an attachment of a mobile node to a network element in a network. A second aspect of the invention relates to a method to be implemented in a mobility anchor node, which detects whether a race condition between registration messages occurs and resolves the most recent location of a mobile node. A third aspect of the invention relates to a method for detecting whether a binding cache entry for a mobile at a correspondent node has been spoofed and to a method for registering a care-of address of a mobile node at a correspondent node. A fourth aspect of the invention relates to a method for providing from a mobile node to a local mobility anchor information on an attachment of a mobile node to a network element.

Abstract: A first aspect of the invention relates to a method for improving security at a local mobility anchor implementing both a network-based and a host-based mobility management scheme for managing the mobility of a mobile node. It suggests a method for verifying an attachment of a mobile node (MN) to a network element in a network. A second aspect of the invention relates to a method to be implemented in a mobility anchor node, which detects whether a race condition between registration messages occurs and resolves the most recent location of a mobile node. A third aspect of the invention relates to a method for detecting whether a binding cache entry for a mobile at a correspondent node has been spoofed and to a method for registering a care-of address of a mobile node at a correspondent node.

Abstract: The invention relates to a method for routing packets in a system of packet-switched networks using different internet protocol versions. The system comprises a plurality of home agents, at least one mobile node and at least one correspondent node. A first mobile node is configured with at least one topologically correct internet protocol address of a first internet protocol version and is located in a network supporting at least routing of packets having a header of the first internet protocol version. The method comprises the following steps. Communication is requested with a first correspondent node being configured with at least an internet protocol address of a second internet protocol version and being located in a network supporting at least the routing of packets having a header of the second internet protocol version, by an application on the first mobile node.

Abstract: To achieve this object the current invention provides a method, a mobile node, a mobile access gateway, a home agent and a communication system for handover of a mobile node between access networks either supporting network based mobility or not supporting network based mobility, in a packet switched communication network comprising at least the mobile, mobile access gateway, a correspondent node and a home agent. The method comprises the steps of performing proxy route optimization towards the correspondent node on behalf of the mobile node, performing handover from a current access network to a target access network, and determining whether the proxy route optimization is needed after the handover.