Telecommunication switching system having adaptive routing switching

Abstract

A telecommunication switching system having switching nodes that perform adaptive routing by utilizing the fact that the switching nodes are arranged in a first and a second hierarchy. In addition, each switching node maintains routing information based on telephone and switching node numbers which identify the switching nodes. A destination switching node transfers its routing information back to an originating switching node which combines that routing information with its own in order to determine shorter call paths for subsequent call routing. The first hierarchy is a dialing plan hierarchy having groups of switching nodes at each dialing plan level. The second hierarchy is a switching node hierarchy based on the switching node number of each switching node with at least one switching node of the switching node hierarchy being at a different level in the dialing plan hierarchy. In order to route a call, a switching node first routes through levels of switching nodes in the dialing plan hierarchy until a second switching node is encountered which can determine the identification of the destination switching node based on a dialed telephone number. The second switching node then routes the call through the node hierarchy using the identified node number until a path is determined to the destination switching node.