Method and apparatus for restoring a network
AssigneeAT&T Corp.
InventorSid Chaudhuri
Life of this patent
Estimating the term…
Abstract
A method and apparatus for restoring communications in a network. The network includes a plurality of nodes, with each pair of nodes connected by a link, and with each link having information channels and restoration channels. An idle signal is sent on each restoration channel for each link. The failure of a link is detected, with the failed link connecting an originating node with a terminating node. In addition, the failed link includes at least one information channel carrying information signals. An alternate path through the network is determined for the information signals using restoration and idle signals sent over the restoration channels. The information signals are then routed from the originating node to the terminating node in accordance with the alternate path.
Claims7
A method for restoring communications in a network, the network having a plurality of nodes, with each pair of nodes connected by a link, with each link having information channels and restoration channels, comprising the steps of:
- sending an idle signal on each restoration channel for each link;
- detecting a failure of a link connecting an originating node with a terminating node, said link having at least one information channel carrying information signals;
- determining an alternate path through the network for said information signals using restoration and idle signals sent over said restoration channels;
- and
- routing said information signals from said originating node to said terminating node in accordance with said alternate path;
- wherein said step for determining said alternate path comprises the steps of:
- sending a restoration signal having a node identification number for said originating node in a restoration channel for each link connected to said originating node;
- sending a restoration signal having a node identification number for said terminating node in a restoration channel for each link connected to said terminating node;
- and
- routing said restoration signals through alternate links and at least one intermediate node until said restoration signal having a node identification number for said originating node reaches said terminating node, and said restoration signal having a node identification number for said terminating node reaches said originating node;
- and
- wherein said step of routing said restoration signals through said intermediate node comprises the steps of:
- a) receiving a first restoration signal over a first restoration channel for a first link at said intermediate node;
- b) sending said first restoration signal over a restoration channel for each link connected to said intermediate node except for said first restoration channel;
- c) receiving a second restoration signal over a second restoration channel for a second link at said intermediate node;
- d) determining whether said node identification number for said first restoration signal matches a said node identification number for said second restoration signal;
- e) sending an idle signal over said second restoration channel if said node identification number for said first restoration signal matches a said node identification number for said second restoration signal;
- f) sending said second restoration signal over said first restoration channel if said node identification number for said first restoration signal does not match said node identification number for said second restoration signal;
- and
- g) performing steps a) to f) for each intermediate node receiving a restoration signal.
Dependencies are inferred from the claim text.