Patent ID: 7146428
Filing Date: 2006-12-05
Classification: H04L,H04W

Abstract:
1. A method of updating a care-of IP address for a mobile host to the mobile host's home agent, where the mobile host departs from a first access network and has been granted access to a second access network, comprising the steps of: sending a care-of address request message containing a sequence number to the home agent in an embedded IP-in-IP packet containing a destination address of a communicating host; receiving an embedded IP-in-IP packet containing a care-of address acknowledgement message from the second access network; checking whether a sequence number in the care-of address acknowledgment message is greater than or equal to the sequence number in the care-of address request message and if so, sending a care-of address confirmation message in outbound IP packets to the home agent after receiving the care-of address acknowledgment message, the care-of address confirmation message containing the same sequence number as the sequence number in the care-of address acknowledgement message.