Experimental demonstration of an access point for HORNET-A packet-over-WDM multiple-access MAN

Hybrid opto-electronic ring network (HORNET) is a novel packet-over-WDM multiple-access network designed by the Stanford Optical Communications Research Laboratory (OCRL) to provide efficient bandwidth sharing among a large number of access points (APs) in a metropolitan area. The HORNET network eliminates the cost and complexity of SONET equipment by transmitting IP/ATM packets directly over the wavelength division multiplexing (WDM) layer. To improve performance above that of a conventional ring network, HORNET employs a multiple-access architecture using fast tunable transmitters and a novel carrier-sense multiple-access with collision avoidance (CSMA/CA) media access control (MAC) protocol. The OCRL has constructed a testbed to demonstrate the ability of a HORNET AP to transmit packets using a fast-tunable transmitter and a novel MAC protocol and to asynchronously receive packets in the packet-over-WDM architecture. The experimental results confirm that HORNET successfully achieves the following functions: 1) fast (low overhead) wavelength tuning using a fast-tunable transmitter; 2) collision-free packet transmission over a multiple-access network via the CSMA/CA MAC protocol; and 3) fast clock and data recovery using the embedded clock tone (ECT) technique.