Method and apparatus for conserving home agent resources in mobile IP deployment

A home agent for use in a wireless communication system supporting mobile Internet Protocol (IP), wherein the home agent is configured to implement a method comprising:

• storing a plurality of mobility bindings, wherein each mobility binding corresponds to an individual mobile node, and wherein each mobility binding comprises:
• a home address provided by the home agent for use by the individual mobile node;
• a care-of address received from the individual mobile node and used by the home agent to forward data to the individual mobile node;
• and
• an inactivity timer to monitor an activity status of the corresponding mobile node;
• monitoring a resource condition that represents a current capacity of a home agent resource, and starting a resource reclaiming process when the resource condition satisfies an overload condition;
• wherein the resource reclaiming process searches each mobility binding of the plurality of mobility bindings for expired inactivity timers, and for each mobility binding with an expired inactivity timer the home agent sends a series of echo request messages to the individual mobile node.

In a wireless communication system supporting mobile Internet Protocol (IP), a method comprising:

• receiving a registration request message at a home agent from a mobile node wherein the registration request message includes a care-of address;
• creating a mobility binding for the mobile node at the home agent, wherein the mobility binding comprises:
• a home address provided by the home agent for use by the mobile node;
• the care-of address;
• and
• an inactivity timer to monitor an activity status of the mobile node;
• entering an overload condition at the home agent;
• starting a reclaiming resources process at the home agent if the inactivity timer has expired;
• and
• sending a series of echo request messages to the mobile node when the inactivity timer has expired.

In a wireless communication system supporting mobile Internet Protocol (IP), a method comprising:

• receiving a registration request message at a home agent wherein the registration request message includes a care-of address;
• providing a home address for a mobile node;
• associating the home address with the care-of address;
• providing an inactivity timer for the mobile node at the home agent;
• monitoring a condition of the home agent;
• starting a reclaiming resources process at the home agent through use of the inactivity timer for the mobile node when the condition satisfies an overload condition;
• and
• sending a series of echo request messages to the mobile node when the condition satisfies the overload condition and when the inactivity timer for the mobile node is expired.

A home agent for use in a wireless communication system supporting mobile Internet Protocol (IP), the home agent comprising:

• means for servicing registration requests from mobile nodes;
• means for providing home addresses to the mobile nodes;
• means for binding the home addresses to care-of addresses;
• means for monitoring the activity of each mobile node individually;
• means for monitoring a resource condition that represents a current capacity of a home agent resource;
• means for reclaiming the home agent resource when the resource condition is overloaded;
• and
• means for sending a series of echo request messages to each mobile node with no activity during a period of time.