Semiconductor optical amplifiers: performance and applications in optical packet switching [Invited]

Semiconductor optical amplifiers (SOAs) are a versatile core technology and the basis for the implementation of a number of key functionalities central to the evolution of highly wavelength-agile all-optical networks. We present an overview of the state of the art of SOAs and summarize a range of applications such as power boosters, preamplifiers, optical linear (gain-clamped) amplifiers, optical gates, and modules based on the hybrid integration of SOAs to yield high-level functionalities such as all-optical wavelength converters/regenerators and small space switching matrices. Their use in a number of proposed optical packet switching situations is also highlighted

A Priority Based Optical Header Contention Resolution in Optical Burst Switching Networks

OBS is a promising switching paradigm for the next-generation Internet.In OBS, data packets are assembled into variable size data burst which are transmitted optically over Dense Wavelength Division Multiplexing(DWDM)networks without O/E/O conversion. The control packet is sent before the data burst to reserve resources and configure switches along the path .The control packet is sent along the separate control channel and goes through O/E/O conversion. We have discussed various OBS signalling protocols and Burst Scheduling Algorithms. As the data channel bandwidth will grow it will lead to the overloading of the control path. In this thesis we have proposed an algorithm to resolve the contention of the optical header. The algorithm assigns the priority to each control packet arriving at the same time .The control packet with highest priority is selected for processing. Simulation results have shown that the technique is effective in improving the throughput

Multiservice QoS-Enabled MAC for Optical Burst Switching

The emergence of a broad range of network-driven applications (e.g., multimedia, online gaming) brings in the need for a network environment able to provide multiservice capabilities with diverse quality-of-service (QoS) guarantees. In this paper, a medium access control protocol is proposed to support multiple services and QoS levels in optical burst-switched mesh networks without wavelength conversion. The protocol provides two different access mechanisms, queue-arbitrated and prearbitrated for connectionless and connection-oriented burst transport, respectively. It has been evaluated through extensive simulations and its simplistic form makes it very promising for implementation and deployment. Results indicate that the protocol can clearly provide a relative quality differentiation for connectionless traffic and guarantee null (or negligible, and thus acceptable) burst loss probability for a wide range of network (or offered) load while ensuring low access delay for the higher-priority traffic. Furthermore, in the multiservice scenario mixing connectionless and connection-oriented burst transmissions, three different prearbitrated slot scheduling algorithms are evaluated, each one providing a different performance in terms of connection blocking probability. The overall results demonstrate the suitability of this architecture for future integrated multiservice optical networks

Information Switching Processor (ISP) contention analysis and control

Future satellite communications, as a viable means of communications and an alternative to terrestrial networks, demand flexibility and low end-user cost. On-board switching/processing satellites potentially provide these features, allowing flexible interconnection among multiple spot beams, direct to the user communications services using very small aperture terminals (VSAT's), independent uplink and downlink access/transmission system designs optimized to user's traffic requirements, efficient TDM downlink transmission, and better link performance. A flexible switching system on the satellite in conjunction with low-cost user terminals will likely benefit future satellite network users