Generalized multiprotocol label switching (GMPLS) has emerged as a very promising technology for the next generation carrier networks. GMPLS successfully combines the best features of IP and ATM in terms of QoS, privacy, flexibility and scalability. Besides, GMPLS introduces enhancements to the existing IP routing and signaling protocols by supporting not only networks that perform packet switching (IP), but also networks that perform switching in the time (TDM), wavelength (DWDM), and space domain (circuit switching).
This paper discusses the design and implementation of a simulation-based GMPLS Optical Router (GOR). We build our GOR model on OPNETtm platform with all the necessary GMPLS functionalities of an optical backbone router, for the GOR to behave as a virtual machine. The description on the essential design features and the key implementation elements of the internal mechanism of GOR form the highlight of this paper. Our virtual GMPLS Optical Router has the capability of giving a more integrated and realistic simulation on wavelength routing, wavelength assignment, wavelength switching, dynamic label switching path (LSP) setup, distributed routing table calculation, and blocking mechanism of GMPLS light paths, all within a scenario. Our simulation results include the blocking rate, which is highly comparable to a real GMPLS optical network. In addition, our proposed GOR is able to provide a simulation platform for further development and future enhancement of GMPLS technologies.
Address/label lookup and data forwarding are the most fundamental functions of a router. Much research work has been concentrated on minimizing the lookup and forwarding time in a high-throughput Terabits router. Though novel algorithms and data structures have been developed to overcome this potential bottleneck, all of these schemes are still processed in the electronic domain. This implies major throughput limitations on electro-optic conversion and processing of packets one at a time (per forwarding engine). In this paper, we attempt to overcome these bottlenecks by introducing multiwavelength optical packet-based processing for table lookup. The distinctive features of this technique include, (1) feasibility of processing (table lookup) packets in their native form, namely optics; (2) enhancing the parallelism to provide a constant time comparison; (3) (capable of) computing in tens of terabits per second. Such processing technique is highly desirable in packet-based networks.