Distributed contention avoidance in Optical Burst-Switched ring networks

Abstract

Abstract-Optical Burst Switching (OBS) is a promising technology for future optical networks. Due to its less complicated implementation using current optical and electrical components, OBS is seen as the first step towards the future Optical Packet Switching (OPS). Regarding network topologies, the ring is extensively used on current metropolitan environments, and this does not seem it will change in the foreseeable future. In this paper we propose a new medium access protocol for Optical Burst-Switched Networks over metropolitan rings that enables the nodes to access the channel in a distributed way. This new protocol avoids burst blockings in transit nodes, turning itself into an efficient and simple burst contention avoidance mechanism. The use of this protocol maximizes the throughput of the network without deteriorating excessively other parameters such as endto-end delay or ingress queues.

On avoiding-minimizing burst collisions in optical burst-switched networks without wavelength conversion

“…In this section we briefly describe the original operation of the protocol that can be found in [5]. Later, we will illustrate some of the enhancements required to use the protocol on a mesh topology.…”

“…In [5], the basic piece of network to enable the use of DAOBS was the optical bus. This bus topology is now extended to a tree-based wavelength topology (see Fig.…”

DQOBSR Protocol with QoS Provisioning for OBS Metro Rings

“…An effective method of addressing the contention is selecting an appropriate MAC protocol. A new MAC protocol, namely, distributed access OBS (DAOBS) is proposed for OBS rings in [2], and later it had been extended for mesh topologies [3]. This protocol is an adaptation of distributed queue dual bus (DQDB) to OBS ring networks.…”