Patent ID: 8325617

Claim:
A communication system comprising: a plurality of branches of a network that are connected to each other via the network, each of the branches comprising: a plurality of end point devices assigned to a branch location for the branch, and a survivability proxy device communicatively connected to the end point devices of the branch; and a switch device connected to the network, the switch device managing communications for the end point devices of the plurality of branches of the network; each of the survivability proxy devices of the plurality of branches providing at least one communication feature for the end point devices of the branch of that survivability proxy device when a network error that isolates the branch of that survivability proxy device from the network occurs; each of the survivability proxy devices sending at least one message to the switch device to poll the switch device after the network error occurs to attempt to re-establish connectivity with the switch device; for each survivability proxy device, the switch device receiving one of the at least one message sent by the survivability proxy device to re-establish connectivity with the switch device and assessing that received message, the received one of the at least one message being in a queue for the switch device; for each survivability proxy device, the switch device assessing the received one of the at least one message sent by the survivability proxy device to re-establish connectivity with the switch device via a method comprising: the switch device determining if the received one of the at least one message indicates that the survivability proxy device is in a normal mode or a survivable mode that is different from the normal mode; upon determining that the survivability proxy device is in the survivable mode, the switch device determining whether to respond to the received one of the at least one message from the survivability proxy device; upon a determination that only the received one of the at least one message from the survivability proxy device is in the queue of the switch device, the switch device responding to the received one of the at least one message from the survivability proxy device to re-establish connectivity; upon a determination that multiple received messages from the survivability proxy devices are in the queue for re-establishing connectivity with the switch device, the switch device determining which of those messages is from the survivability proxy device having a greatest priority and first processing that message for re-establishing connectivity with the survivability proxy device having the greatest priority.