D. Wonglumsom

HORNET: a packet-over-WDM multiple access metropolitan area ring network

Current metropolitan area networks (MANs) based on the SONET transport are not developing at the rate required to support the phenomenal increase in data traffic. To address the needs of future MANs, the Optical Communications Research Laboratory at Stanford University and Sprint Advanced Technology Laboratories are building HORNET (Hybrid Optoelectronic Ring NETwork). HORNET has a multiple access architecture, in which nodes access any WDM channel using a novel media access control protocol and fast tunable laser transmitters. HORNET transports data packets directly over the WDM ring, eliminating the SONET transport. This paper presents the HORNET architecture, the node design consisting of novel packet-over-WDM components, and the experimental testbed with results.

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.

CSMA/CA MAC protocols for IP-HORNET: an IP over WDM metropolitan area ring network

As data traffic increases exponentially, IP over WDM transport will replace conventional SONET transport in metropolitan area networks. Such networks will require new media access control (MAC) protocols to efficiently share network bandwidth among multiple network nodes. This paper describes and evaluates novel and practical carrier sense multiple access with collision avoidance (CSMA/CA) MAC protocols for IP over WDM ring networks that handle variable size IP packets without complex variable optical delays or centralized algorithms. Simulation results show that the proposed IP-MAC protocols are efficient and comparable to our selected benchmark and will be implemented in the IP-HORNET testbed.

Experimental demonstration of a novel media access protocol for HORNET: a packet-over-WDM multiple-access MAN ring

As packet-based traffic in the metropolitan area network continues to exponentially increase, and as content and applications become more distributed, conventional metropolitan area networks fail to function efficiently. Sprint Advanced Technology Laboratories and Stanford Universitys Optical Communications Research Laboratory are developing a new network called HORNET (hybrid opto-electronic ring network), which is optimized for bursty, unpredictable, packet-based traffic patterns with distributed sources and destinations. HORNET uses fast tunable transmitters and a novel media access control scheme to realize a packet-over-WDM multiple-access ring architecture. The experimental demonstration of the novel media access control scheme is presented in this work.

WDM metropolitan area network based on CSMA/CA packet switching

The bursty nature of traffic in metropolitan area networks results in underutilized and inefficient SONET networks. The hybrid optoelectronic ring network (HORNET) is a network being developed at the Optical Communications Research Laboratory at Stanford University to address the problems of SONET transport in metropolitan area networks (MANs). HORNET performs packet switching using a fast-tunable wavelength transmitter, which hops to different wavelengths on a packet-by-packet basis. In this letter, we present simulation results which quantify the benefits of a wavelength tunable transmitter in a packet switched wavelength-division-multiplexed MAN. We show that a tunable transmitter is able to take advantage of imbalances in wavelength utilization, and provides a 45% improvement in packet latency characteristics. We also show that in order to maintain these benefits the tuning time of the transmitter cannot exceed 10% of the packet transmit time.

Architecture and protocols for HORNET: a novel packet-over-WDM multiple-access MAN

Future Internet technologies will cause an evolution in metropolitan area networks throughout the following decades. To keep pace with the development of Internet access technologies and devices, we have created a novel architecture called HORNET. Through the use of ultra-fast tunable transmitters and packet-over-WDM technology, HORNET is optimized for the metro area traffic of the future. We have developed a novel media access protocol and a novel survivability protocol for HORNET that we describe here. Also, we have generated successful experimental results, including a demonstration of the media access protocol and 4-ns wavelength switching durations in the tunable transmitter.

HORNET-A packet-switched WDM network: optical packet transmission and recovery

The hybrid optoelectronic ring network (HORNET) is a novel packet-switched wavelength-division-multiplexed metropolitan area network (MAN). HORNET uses a combination of optical and electronic packet-switching and an optical carrier sense multiple access with collision avoidance (CSMA/CA) media access scheme to efficiently provide large bandwidth to many users. The HORNET optical packets consist of 2.5-Gb/s payload data, an embedded 2.5-GHz clock tone, and a subcarrier-multiplexed (SCM) header for CSMA/CA. We are constructing an experimental testbed to demonstrate the ability of HORNET nodes to transmit and receive packets, to recover the destination node address carried by the SCM header, and to perform fast clock and data recovery with minimal overhead within the HORNET packet receiver.

The architecture of HORNET: A packet-over-WDM multiple-access optical metropolitan area ring network

Abstract To cost-effectively address the phenomenal demand for bandwidth in the metropolitan area, the Optical Communications Research Laboratory at Stanford University and Sprint Advanced Technology Laboratories have developed a novel architecture for a large-scale metropolitan area network (MAN). The network, which is called HORNET, is a packet-over-WDM multiple-access network featuring the use of fast-tunable transmitters and a novel “CSMA/CA” media access protocol to improve network efficiency well beyond that of today’s solution. This paper presents the design and implementation of the network architecture and gives an analytical discussion of its advantages.

Experimental demonstration of a media access protocol for HORNET: a WDM multiple access metropolitan area ring network

We experimentally demonstrate a novel CSMA/CA protocol for HORNET: a WDM multiple access MAN ring. HORNET uses subcarrier multiplexed tones to govern access to wavelengths, and a fast-tunable transmitter to allow the node to transmit on all wavelengths.

HORNET: A Packet-Switched WDM Metropolitan Area Network

HORNET is a metro network designed to better face the challenges offered by next generation metropolitan area networks. HORNET uses a packet-over-WDM transport on a bi-directional ring network. Fast-tunable packet transmitters and wavelength routing enable it to scale cost-effectively to ultra-high capacities. A control-channel-based MAC protocol enables the nodes to share the bandwidth of the network while preventing collisions. The MAC protocol is designed to transport variable-sized IP packets and guaranteed bit-rate circuits while maintaining fairness in the network. Survivability protocols protect circuit and best effort traffic against a fiber cut or node failure. A burst mode receiver, in conjunction with the tunable transmitter and constant gain optical amplifiers make up the essential sub-systems inside a node. This article summarizes the accomplishments of the HORNET project, including the design, analysis, and demonstration of the architecture, protocols, sub-systems and testbed. As this work shows, the HORNET architecture is an excellent candidate for next-generation high-capacity metro networks.