Mobile ip addressing

Abstract

A system and method are provided for mobile Internet Protocol (IP) addressing, in a multi-mode wireless communications access terminal (AT). The method provides an AT with an IP address (ATA), and a care-of-address (CoA) in each of a plurality of networks. In one aspect, the AT selects a first network for transmission, from the plurality of networks. The AT sends an IP packet to a correspondent node (CN) via a first mobile node (MN) external device. Regardless of the network selected, the AT is able to use the ATA as a source address. Sending the IP packet to the CN may include creating a tunnel between the first MN and the HA. The IP packet is sent to the HA using the first CoA as a tunnel source address, and the HA sends the IP packet to the CN using the ATA as the source address.

1 . In a multi-mode wireless communications access terminal (AT), a method for mobile Internet Protocol (IP) addressing, the method comprising:
 providing an AT having an IP address (ATA) and a care-of-address (CoA) in each of a plurality of networks;   from the plurality of networks, selecting a first network for transmission; and,   sending an IP packet to a correspondent node (CN) via a first mobile node (MN) external device, using the ATA as a source address.   
   
   
       2 . The method of  claim 1  further comprising:
 selecting a second network for transmission; and,   sending an IP packet to the CN via a second MN external device using the ATA as the source address.   
   
   
       3 . The method of  claim 1  further comprising:
 selecting the second network for transmission, in addition to the first network; and,   sending IP packets to the CN via the first MN with a first CoA, and via a second MN with a second CoA, using the ATA as the source address.   
   
   
       4 . The method of  claim 1  wherein providing the AT having the ATA and the CoA in each of a plurality of networks includes creating a tunnel between the first MN and the HA;
 wherein sending the IP packet to the CN includes:
 sending the IP packet to the HA using the first CoA as a tunnel source address; and 
 sending the IP packet from the HA to the CN using the ATA as 
   the source address.   
   
   
       5 . The method of  claim 4  further comprising:
 registering the CoAs with the HA, from a source selected from the group consisting of the AT, the MN, and a combination of the AT and the MN.   
   
   
       6 . A multi-mode wireless communications access terminal (AT) system for sending Internet Protocol (IP) packets using mobile IP (MIP) addressing, the system comprising:
 an AT comprising:
 a plurality of communication subsystems having wireless transceivers for communicating with external device mobile units (MNs) in a corresponding plurality of networks; and, 
 a MIP addressing module having communication subsystem interfaces and an AT IP address (ATA) cross-referenced to a care-of-address (CoA) for each of the plurality of MNs, the MIP addressing module selecting a first network for transmission, and sending an IP packet to a correspondent node (CN) using the ATA as the source address, via a first MN. 
   
   
   
       7 . The system of  claim 6  wherein the AT MIP addressing module selects a second subsystem for transmission, and sends an IP packet to the CN using the ATA as the source address, via a second MN. 
   
   
       8 . The system of  claim 6  wherein the AT MIP addressing module selects the second subsystem for transmission, in addition to the first subsystem, and sends IP packets to the CN using the ATA as the destination address, via the first MN associated with the first network, and via a second MN associated with a second network. 
   
   
       9 . The system of  claim 6  further comprising:
 a first MN having a first network interface for receiving the IP packet from the AT with the ATA listed as the source address, the first MN having a tunnel interface for sending the IP packet, using a first CoA as the tunnel source address; and   a home agent (HA) having a tunnel interface for receiving the IP packet from the first MN, and a network interface to sending the IP packet to the CN with the ATA listed as the source address.   
   
   
       10 . The system of  claim 9  wherein the CoAs are registered with the HA, from a source selected from the group consisting of the AT, the MN, and a combination of the AT and the MN. 
   
   
       11 . A multi-mode wireless communications access terminal (AT) processing device for sending Internet Protocol (IP) packets using mobile IP (MIP) addressing, the processing device comprising:
 interfaces for a plurality of communication subsystems wirelessly communicating with external device mobile units (MNs) in a corresponding plurality of networks;   a memory for storing an AT IP address (ATA); and,   a network address selector for sending an IP packet to a correspondent node (CN) using the ATA as the source address, via a first MN with a first care-of-address (CoA).   
   
   
       12 . The processing device of  claim 11  wherein the network address selector receives an IP packet from the CN with the ATA listed as the destination address, via the first MN. 
   
   
       13 . A multi-mode wireless communications access terminal (AT) with means for sending Internet Protocol (IP) packets using mobile IP (MIP) addressing, the AT comprising:
 means for wirelessly communicating with external device mobile units (MNs) in a plurality of networks; and,   means for network selection, having an AT IP address (ATA) cross-referenced to a care-of-address (CoA) for each of the plurality of MNs, the network selection means selecting a first network for transmission and sending an IP packet to a correspondent node (CN) using the ATA as the source address, via a first MN.   
   
   
       14 . The AT of  claim 13  wherein the network selection means receives an IP packet from the CN with the ATA listed as the destination address, via the first MN. 
   
   
       15 . In a multi-mode wireless communications access terminal (AT), a signal bearing medium tangibly embodying a program of machine-readable instructions executable by a digital processing apparatus to perform operations for mobile Internet Protocol (IP) addressing, the operations comprising:
 providing an AT having an IP address (ATA) and a care-of-address (CoA) in each of a plurality of networks;   from the plurality of networks, selecting a first network for transmission; and,   sending an IP packet to a correspondent node (CN) via a first mobile node (MN) external device, using the ATA as a source address.