Patent ID: 7895648

Claim:
A method of providing a secure connection from a first end machine to a second end machine, said method being performed in said first end machine, said method comprising: negotiating a first set of attributes of a security association (SA) with said second end machine, wherein said first set of attributes are used to provide said secure connection to said second end machine; sending to said second end machine a first packet using said SA, wherein said first end machine is assigned a self address equaling a first address such that said first packet is sent with said first address and using said SA; detecting that said self address is changed to a new address; sending a request to said second end machine, wherein said new address is contained in a payload portion of a packet forming said request, said request indicating that said self address has changed to said new address, and wherein the change from the self address to the new address triggers an Internet Security Association and Key Management Protocol (ISAKMP) element to evaluate a SA table to determine selected SAs in a security parameter Index (SPI) list that are bound to the self address, and wherein the SPI list is provided in an outgoing IP address update message to the second end machine; and sending to said second end machine a second packet using said SA, wherein said second packet contains said new address as a source address, wherein the first end machine is configured to send an update address request to a gateway providing connectivity to the first end machine, the update address request indicating the new address is to be bound to the SA, the first end machine being further configured to receive an acceptance message from the gateway, the acceptance message signifying that the new address is bound to the SA such that a flow is facilitated by the second machine using the SA and using the first set of attributes, wherein if the acceptance message is not received within a specified time, an assumption is made that the update address request has not been received and the first set of attributes are renegotiated for the new address for communications involving the gateway.