Method of source routing in an asynchronous transfer mode network when a node is in an overload state

In an asynchronous transfer mode (ATM) network, a method of source routing a call originating from a setup message generated by a source user connected to a first node in an overload state to a non-local destination user connected to a second user, said first node connected to a neighboring node not in an overload state via a communication link, said method comprising the steps of:

• prioritizing a topology database memory within said first node in response to said first node discovering it is in an overload state;
• generating and flooding, on said first node, an overload routing message indicating to the neighbors of said first node that said first node is in the overload state;
• choosing at least one neighboring node connected to said first node that is not in an overload state;
• determining if the communication link between said chosen neighboring node connected to said first node is in a full state;
• determining if said chosen neighboring node connected to said first node supports overload routing;
• calculating a route, on said chosen neighboring node, based at least on the data provided within said setup message;
• transmitting said calculated route to said first node;
• and
• processing said call by said first node utilizing said route calculated on said chosen neighboring node.