A summary of the HORNET project: a next-generation metropolitan area network

Metropolitan area networks are currently undergoing an evolution aimed at more efficiently transport of data-oriented traffic. However, the incoming generation of metro networks is based on conventional technology, which prevents them scaling cost-effectively to ultrahigh capacities. We have developed a new architecture and set of protocols for the next generation of metro networks. The architecture, named HORNET (hybrid optoelectronic ring network), is a packet-over-wavelength-division multiplexing ring network that utilizes fast-tunable packet transmitters and wavelength routing to enable it to scale costeffectively to ultrahigh capacities. A control-channel-based media access control (MAC) protocol enables the network nodes to share the bandwidth of the network while preventing collisions. The MAC protocol is designed to transport variable-sized packets and to provide fairness control to all network end users. The efficiency and the fairness of the MAC protocol is demonstrated with custom-designed simulations. The implementation of the MAC protocol and the survivability of the network have been demonstrated in a laboratory experimental testbed. The article summarizes the accomplishments of the HORNET project, including the design, analysis, and demonstration of a metro architecture and a set of protocols. The HORNET architecture is an excellent candidate for next-generation high-capacity metro networks.