Design of a hybrid packet and circuit switching network node

Efforts of realizing all optical packet switching have been overwhelming in the past decade. While optical packet switching remains an attractive switching paradigm in the long run, technical challenges prohibit it from becoming a practical solution for the ever-growing bandwidth hunger during the next few years. Finding a technically viable way to meet the increasing capacity requirement with good scalability and flexibility becomes a clear pursue for the community. Hybrid packet and circuit switching is considered to be one promising technique in realizing high performance switching at low cost and efficient energy consumption, by taking advantage of both packet switching and circuit switching. In this paper, we review existing work in hybrid optical packet and circuit switching. We discuss the key technical challenges in realizing hybrid optical packet and circuit switching. We further introduce our ongoing efforts in building a seamlessly transformable packet/circuit-switching node with hybrid optical and electronic components. With in-band signaling and electronic line card processing, the node is capable of operation in 100% packet switching, 100% circuit switching, or anything in between. The implemented node is believed to be a good research testbed for packet/circuit-switching co-existence in a single node.