Communication control method, communication node, and mobile node

Abstract

Disclosed is a technique which, when an MN (mobile node) has one or a plurality of HoAs (home addresses) and a packet is transmitted from a CN (correspondent node) through an HA (home agent) to the MN, reduces a delay stemming from registration processing on binding information or selection processing among the plurality of HoAs and a delay of communication due to a result of the selection. According to this technique, an MN 100 notifies, to the CN, home network connection information indicative of whether or not it is currently in connection with a home network which has allocated its own plurality of HoAs, an address of each HA and an ID of each HA in a state associated with the plurality of HoAs. On the basis of the information received from the MN, an CN 150 grasps the home network with which the MN is currently in connection and makes an inquiry about the condition of the HA and sets an appropriate HoA, judged on the basis of the grasping result or the inquiry result, as a destination address of a packet to be transmitted to the MN.

1 . A communication control method for a communication between a mobile node to which a plurality of home addresses are allocated and a predetermined communication node, wherein said mobile node notifies, to said predetermined communication node, information enabling a selection of a home address, which is preferably set as a destination address of a packet, when the packet is transmitted from said predetermined communication node to said mobile node. 
     
     
         2 . The communication control method according to  claim 1 , comprising:
 a mobility association information notifying step in which said mobile node notifies, to said predetermined communication node, information on association of the plurality of home addresses of said mobile node between home network connection information indicative of whether or not said mobile node is currently in connection with one or a plurality of home networks which have allocated the plurality of home addresses;   a home address specifying step in which, when said predetermined communication node transmits a packet to said mobile node, said predetermined communication node makes reference to the home network connection information to specify a home network with which said mobile node is currently in connection; and   a destination address setting step in which said communication node sets the home address of said mobile node, associated with the home network specified in said home address specifying step, as a destination address of the packet.   
     
     
         3 . The communication control method according to  claim 2 , comprising a care-of-address acquiring step in which, when said mobile node is currently in connection with one or a plurality of home networks which have allocated the plurality of home addresses, said mobile node acquires a care-of address compatible with the home network,
 wherein, in said mobility association information notifying step, the care-of address acquired in said care-of-address acquiring step is used as the home network connection information.   
     
     
         4 . The communication control method according to  claim 1 , comprising:
 a mobility association information notifying step in which said mobile node notifies, to said predetermined communication node, information on association among the plurality of home addresses of said mobile node, addresses of one or a plurality of home agents managing the plurality of home addresses and home agent ID information enabling the identification of each of said plurality of home agents;   a home agent inquiring step in which said predetermined communication node makes an inquiry at each of said plurality of home agents, identified by the home agent ID information, about a condition of said home agent;   a home agent selecting step in which said predetermined communication node selects a home agent, through which a packet to be transmitted from said predetermined communication node to said mobile node passes, on the basis of a result of the inquiry in said home agent inquiring step; and   a destination address setting step in which the home address of said mobile node associated with said home agent selected in said home agent selecting step is set as the packet destination address.   
     
     
         5 . The communication control method according to  claim 1 , comprising:
 a mobility association information notifying step in which, when said mobile node has a plurality of communication interfaces each connectable to a different network and is connected to a home network through at least one of said plurality of communication interfaces, said mobile node notifies, to said predetermined communication node, information on association between home network connection information indicative of the home address which is currently connection with the home network and the fact that said home address is currently in connection with the home network and an address allocated to a different communication interface which is not connected to the home network; and   an destination address setting step in which, when said predetermined communication node transmits a packet to said mobile node, said predetermined communication node selects and sets a destination address to be set as a destination address of the packet, from the home address which is currently in connection with the home network and the address allocated to the different communication interface.   
     
     
         6 . The communication control method according to  claim 1 , comprising a selection function notifying step in which said predetermined communication node notifies the fact that said predetermined communication node has a home address selection function to select the home address preferably set as a destination address of a packet when the packet is transmitted from said predetermined communication node to said mobile node. 
     
     
         7 . The communication control method according to  claim 6 , wherein said predetermined communication node is a home agent for said mobile node and, in said selection function notifying step, said predetermined communication node transmits a router advertisement message including information indicating that said predetermined communication node has said home address selection function so as to notify the fact that said predetermined communication node has said home address selection function, to said mobile node connected to a network in which said predetermined communication node exists. 
     
     
         8 . A communication node, which makes a communication with a mobile node to which a plurality of home addresses are allocated, comprising:
 mobility association information acquiring means for receiving, from said mobile node, information on association between the plurality of home addresses of said mobile node and home network connection information indicative of whether or not said mobile node is currently in connection with one or a plurality of home networks which have allocated the plurality of home addresses;   home address specifying means for, when a packet is transmitted to said mobile node, making reference to the home network connection information to specify a home network with which said mobile node is currently in connection; and   destination address setting means for setting the home address of said mobile node, associated with the home network specified by said home address specifying means, as a destination address of the packet.   
     
     
         9 . A communication node, which makes a communication with a mobile node to which a plurality of home addresses are allocated, comprising:
 mobility association information acquiring means for notifying, from said mobile node, information on association among the plurality of home addresses of said mobile node, addresses of one or a plurality of home agents managing the plurality of home addresses and home agent ID information enabling an identification of each of said plurality of home agents;   home Agent inquiry executing means for, when a packet is transmitted to said mobile node, making an inquiry at each of said plurality of home agents identified on the basis of the home agent ID information at about a condition of the home agent;   home agent selecting means for selecting a home agent, through which a packet to be transmitted to said mobile node passes, on the basis of a result of the inquiry acquired by said home agent inquiry executing means; and   destination address setting means for setting the home address of said mobile node, associated with the home agent selected by said home agent selecting means, as a destination address of the packet.   
     
     
         10 . A communication node, which makes a communication with a mobile node to which one or a plurality of home addresses are allocated, with said mobile node having one or a plurality of communication interfaces connectable to a home network and a foreign network and said mobile node being connected to the home network through at least one of said one or plurality of communication interfaces, comprising:
 mobility association information acquiring means for receiving, from said mobile node, information on association between home network connection information indicative of the current connection with the home network and an address allocated to a different communication interface which is not in connection with the home network; and   destination address setting means for, when a packet is transmitted to said mobile node, selecting and setting a destination address, as a destination address of the packet, from the home address which is currently in connection with the home network and the address allocated to said different communication interface.   
     
     
         11 . The communication node according to  claim 10 , wherein a care-of address acquired in the home network with which said mobile node is currently in connection is used as the home network connection information indicative of the current connection with the home network. 
     
     
         12 . A mobile node to which one or a plurality of home addresses are allocated, comprising mobility association information notifying means for notifying, to a predetermined communication node, home network connection information indicative of whether or not its own communication interface is currently in connection with one or a plurality of home networks which have allocated the home addresses. 
     
     
         13 . A mobile node to which a plurality of home addresses are allocated, comprising mobility association information notifying means for notifying, to a predetermined communication node, information on association among its own plurality of home addresses, addresses of one or a plurality of home agents managing the plurality of home addresses and home agent ID information enabling identification of each of said plurality of home agents. 
     
     
         14 . A mobile node to which one or a plurality of home addresses are allocated, with said mobile node having one or a plurality of communication interfaces connectable to a home network and a foreign network and said mobile node being connected to the home network through at least one of said one or plurality of communication interfaces, comprising mobility association information notifying means for notifying, to a predetermined communication node, information on association between home network connection information indicative of the current connection with the home network and an address allocated to a different communication interface which is not in connection with the home network. 
     
     
         15 . The mobile node according to  claim 14 , comprising care-of-address acquiring means for acquiring a care-of address compatible with the home network with which said mobile node is currently in connection,
 wherein said mobility association information notifying means uses the care-of address, acquired by said care-of-address acquiring means, as the home network connection information.