An addressing independent networking structure favorable for all-optical packet switching

Abstract

All-optical packet switching (AOPS) technology is essential to fully utilize the tremendous bandwidth provided by advanced optical communication techniques through forwarding packets in optical domain for the next generation network. However, long packet headers and other complex operations such as table lookup and packet header re-writing still have to be processed electronically for lack of cost-effective optical processing techniques. This not only increases system complexity but also limits packet forwarding speed due to optical-electronic-optical conversion. Lots of work of improving optical processing techniques to realize AOPS is reported in the literature. Differently, this paper proposes a new networking structure to facilitate AOPS realization and support various existing networks through simplifying networking operations. This structure only requires an AOPS node to process a short packet header to forward packets across it with neither table lookup nor header re-writing. Furthermore, it moves high layer addressing issues from packet forwarding mechanisms of routers. Consequently, any changes in addressing schemes such as address space extension do not require changes in the AOPS nodes. It can also support both connection-oriented and connectionless services to carry various types of traffic such as ATM and IP traffic. This structure is mainly based on the hierarchical source routing approach. The analytical results show that average packet header sizes are still acceptable even for long paths consisting of many nodes each of which has a large number of output ports.