Method and apparatus for maintaining IP connectivity with a radio network

A method for maintaining an Internet Protocol (IP) session for an access terminal at a first radio network, the method comprising:

• establishing the IP session for the access terminal with a network element via the first radio network, wherein the access terminal is assigned a first address for the IP session;
• receiving a request to maintain the IP session if the access terminal is not tuned to the first radio network via the first radio network;
• receiving a forwarding address for the access terminal via the first radio network;
• receiving an indication that the access terminal is not tuned to the first radio network;
• receiving a first packet from the network element and addressed to the access terminal using the first address;
• sending a second packet to the network element in response to reception of the first packet, wherein the second packet is addressed to the access terminal using the forwarding address and indicates that the first radio network has data for the access terminal;
• establishing a connection with the access terminal via the first radio network;
• and
• sending the first packet to the access terminal via the first radio network.

A method for maintaining an Internet Protocol (IP) session for an access terminal at a first radio network, the method comprising:

• establishing the IP session with a network element via the first radio network,
• establishing a second session with a second radio network;
• sending to the first radio network a request to maintain the IP session if not tuned to the first radio network;
• sending a forwarding address to the first radio network;
• receiving a communication from the second radio network;
• establishing a connection with the first radio network in response to the received communication;
• and
• receiving a packet from the first radio network.

A method for maintaining an Internet Protocol (IP) session for an access terminal at a first radio network, the method comprising:

• establishing the IP session with a network element via the first radio network;
• receiving an assignment of a first address for the IP session;
• establishing a second session with a second radio network;
• receiving an assignment of a second address for the second session;
• maintaining a protocol stack for the IP and second sessions, wherein the protocol stack includes the first and second addresses to be used for the IP and second sessions established via the first and second radio networks, respectively;
• sending to the first radio network a request to maintain the IP session if not tuned to the first radio network;
• sending the second address as a forwarding address to the first radio network;
• receiving a page from the second radio network;
• establishing a connection with the first radio network in response to the received page;
• and
• receiving a packet from the first radio network.

An access terminal comprising:

• a transmitter unit operative to receive and code data and messages, modulate the coded data, and convert the modulated data into a first modulated signal suitable for transmission over a transmission medium;
• a receiver unit operative to receive a second modulated signal, demodulate the received signal to provide demodulated data, and decode the demodulated data to recover transmitted data and messages;
• and
• a controller coupled to the transmitter and receiver units and operative to direct
• establishment of an IP session with a network element via a first radio network,
• establishment of a second session with a second radio network,
• transmission to the first radio network a request to maintain the IP session while not tuned to the first radio network,
• transmission of a forwarding address to the first radio network,
• reception of a communication from the second radio network,
• establishment of a connection with the first radio network in response to the received communication from the second radio network, and
• reception of a packet from the first radio network.

An access point in a first radio network, comprising:

• a transmitter unit operative to receive and code data and messages, modulate the coded data, and convert the modulated data into a first modulated signal suitable for transmission over a transmission medium;
• a receiver unit operative to receive a second modulated signal, demodulated the received signal to generate demodulated data, and decode the demodulated data to recover transmitted data and messages;
• and
• a processor coupled to the transmitter and receiver units and configured to direct
• establishment of an IP session for an access terminal with a network element,
• reception of a request to maintain the IP session if the access terminal is not tuned to the first radio network,
• reception of a forwarding address for the access terminal via the first radio network,
• reception of an indication that the access terminal is not tuned to the first radio network,
• reception of a first packet for the access terminal via the first radio network,
• transmission of a second packet in response to reception of the first packet, wherein the second packet is addressed to the access terminal using the forwarding address and indicates that the first radio network has data for the access terminal,
• establishment of a connection with the access terminal via the first radio network, and
• transmission of the first packet to the access terminal via the first radio network.