Ein selbstverwaltendes verbindungsorientiertes Kommunikationssystem

Most of today's telecommunication systems are configured and controlled by central management systems. During the operation a permanent monitoring of the network takes place to detect breakdowns of nodes and links and to control necessary re-configuration tasks. Administrative procedures are done automatically by appropriate algorithms only in some cases. Communication networks are still increasing. New switching systems and transmission lines must be continuously integrated and the network infrastructure must be adopted. Consequently, a self-organizing telecommunication architecture would be helpful, to simplify the operation of such networks. Configuration and control is then done by the network itself in a distributed way. A central management is no longer necessary. A main item during the development of such a self-organizing architecture in this thesis was the creation of an open and stable system. Thus, a modular protocol stack for routing and for signaling in connection-oriented communication systems is specified. Routing is based on a virtual hierarchical network representation to enable scalability. The network organization is build up automatically in a distributed way by clustering mechanism running in each node. A neighborhood detection protocol and a topology state protocol provides the nodes with the necessary information to maintain the network representation and to calculate routes. As a node has only a restricted view of the network, a source routing mechanism is used. Each node has a unique address identifying its location in the hierarchical network. As there is either no central management nor the network representation is static, a new address format and a distributed address assignment algorithm is specified. If the network representation changes, the addresses are adopted to these new conditions. Signaling is based on the User Network Interface (UNI) of the ATM Forum. This specification defines a number of basic messages and functions to establish and to control connections. Extensions are done to support the hierarchical network representation and to provide a crankback mechanism to enable alternate routing. Summarizing, the approach presented in this thesis realizes a complete self-managed connection-oriented telecommunication system. The modular protocol stack gives flexibility for further developments without functional restrictions.