Optical Packet Switching: Approach to Performance Modeling and Simulation (original) (raw)

Optical Packet Switching

Computer Communications and Networks, 2009

In the last few years research on WDM optical packet-switching has mainly concentrated on issues at the single node level. The goal of this paper is to discuss about the problems arising when the focus is moved toward a network-wide scope. In particular, an overview of routing techniques that may be adopted in an optical packet-switched backbone is presented, showing the effects of adaptive multi-path routing strategies on the network performance. Furthermore, performance differentiation based on different routing and contention resolution strategies is proposed and analyzed in a simple QoS-aware scenario. Then, the application of adaptive routing strategies to network recovery in case of single link failure and the effects of dynamic multi-wavelength management and multi-path routing on packet sequence are also discussed.

Photonic Packet Switches: Architectures and Experimental Implementations

Photonic packet switches offer high speed, data rate and format transparency, and flexihility required by future computer com munications and cell-based telecommunications networks. In this paper, we review experimental progress in state-of-the-art pho tonic packet switches with an emphasis on all-optical guided-wave systems. The term all-optical implies that the data portion of a packet remains in opticalformat from the source to the destination.

Photonic packet switching: An overview

1999

The application of photonic technologies to packet switching offers the potential of very large switch capacity in the terabit per second range. The merging of packet switching with photonic technologies opens up the possibility of packet switching in transparent photonic media, in which packets remain in optical form without undergoing optoelectronic conversion. This paper reviews recent work on photonic packet switching. Different approaches to photonic packet switching and key design issues are discussed.

Transparent optical packet switching: network architecture and demonstrators in the KEOPS project

IEEE Journal on Selected Areas in Communications, 1998

This paper reviews the work carried out in the ACTS KEOPS (Keys to Optical Packet Switching) project, describing the results obtained to date. The main objective of the project is the definition, development, and assessment of optical packet switching and routing networks, capable of providing transparency to the payload bit rate, using optical packets of fixed duration and low bit rate headers in order to enable easier processing at the network/node interfaces. The feasibility of the KEOPS concept is assessed by modeling, laboratory experiments, and testbed implementation of optical packet switching nodes and network/node interfacing blocks, including a fully equipped demonstrator. The demonstration relies on advanced optoelectronic components, developed within the project, which are briefly described.

Optical Packet Switching and Associated Optical Signal Processing

In this talk we will review functions for optical packet switching and ultra-fast network functions that can be handled using all-optical signal processing technologies. We will review research results utilizing ultra-fast all-optical nonlinear fiber wavelength converters and InP integrated optical wavelength converters. Application to all-optical label swapping and WDM/OTDM networks will be discussed. Introduction Within today's Internet, data is transported using optical fiber transmission and wavelength division multiplexing (WDM) systems that today carry a typical 32-80 wavelengths modulated at 2.5 Gbps to 10 Gbps per wavelength. Today's routers and electronic switching systems need to handle almost 0.5 Terabit per second in order to redirect incoming data from fully loaded WDM links. Things become interesting when we consider that the capacity of optical fibers continues to double every 8-12 months. Today's state-of-the-art single fiber capacity exceeds 10 Tbps. Comparing this increase with that of electronic processor speeds which doubles every 18 months (Moore's Law) and comes at the expense of increased chip power dissipation we see that there is a potential bandwidth mismatch in handling capability between fiber transmission systems and electronic routers and switching systems. The story is more complex when we consider that future routers and switches will potentially terminate hundreds or thousands of optical wavelengths and the increase in bit-rate per wavelength will head out to 40 Gbps and beyond to 160 Gbps. Additionally, electronic memory access speeds only increase at the rate of approximately 5% per year, an important data point since memory plays a key role in how packets are buffered and directed through the router. It is not difficult to see that the process of moving a massive number of packets per second (100 million packets/second and beyond the 1 Billion packets/second mark) through the multiple layers of electronics in a router, can lead to router congestion and exceed the performance of electronics and the ability to efficiently handle the dissipated power.

Design and Analysis of Optical Packet Switch Routers

Advances in Wireless Technologies and Telecommunication

Optical packet switching is connectionless networking solution through which we can get high speed data transfer and optimum bandwidth utilization using wavelength division multiplexing technique. For realizing optical packet switching the numbers of optical packet switch architectures are available in market. In this chapter the authors discuss the overall development of optical packet switching; some recently published optical packet switch architectures are discussed in the chapter and a comparison is performed between the switches through loss, cost and buffer analysis.

All-optical techniques enabling packet switching

2007 ICTON Mediterranean Winter Conference, 2007

Scalability of packet switched cross-connects that utilize all-optical signal processing is a crucial issue that eventually determines the future role of photonic signal processing in optical networks. After reviewing several labeling techniques, we discuss label stacking and label swapping techniques and their benefits for scalable optical packet switched nodes. All-optical devices for implementing the packet switch based on the labeling techniques will be described. Finally, we present a 1×4 all-optical packet switch based on label swapping technique that utilizes a scalable and asynchronous label processor and label rewriter. Error-free operation indicates a potential utilization of the swapping technique in a multihop packet-switched network.

Design Criteria of High Speed Optical Packet Switching Network

-Optical packet switching enables the transfer of packet signals in the optical domain on a packet-by-packet basis. In conventional electronic routers, all input optical packets are converted into electrical signals that are subsequently stored in a memory. Optical packet switching is promising to offer large capacity and data transparency. However, after many years of research, this technology has not yet been applied in actual products, because of the lack of deep and fast optical memories and the poor level of integration. It will be overcome not only through technical breakthroughs but also through clever network design, making optimal use of optics and electronics. Developments in OPS seem to lead integration of optical and electronic networks and the use of optical burst switching (OBS). High-speed digital fiber-optic transmission using subcarrier multiplexing(SCM) is investigated both analytically and numerically. In order to reduce the impact of fiber chromatic dispersion and increase bandwidth efficiency, optical single-sideband (OSSB) modulation was used. Because frequency spacing between adjacent subcarriers can be much narrower than in a conventional. Dense Wavelength Division Multiplexing (DWDM) is an optical multiplexing technology used to increase bandwidth over existing fiber networks system, nonlinear crosstalk must be considered. Although chromatic dispersion is not a limiting factor in SCM systems because the data rate at each subcarrier is low, polarization mode dispersion (PMD) has a big impact on the system performance if radiofrequency (RF) phase detection is used in the receiver. In order to optimize the system performance, tradeoffs must be made between data rate per subcarrier, levels of modulation, channel spacing between subcarriers, optical power, and modulation indexes. A 10-Gb/s SCM test bed has been set up in which 4×2.5 Gb/s data streams are combined into one wavelength that occupies a 20-GHz optical bandwidth. OSSB modulation is used in the experiment. The measured results agree well with the analytical prediction. In the optical domain, the Optical Packet Switching(OPS) paradigm is similar to electronic packet switching, except that the payload of the packets are switched and buffered in the optical domain while the headers, which contain control information, are processed electronically. In this paper, we focus on slotted OPS networks, where optical packets are of a fixed duration, and are aligned at the inputs of the switching node. Slotted OPS with a packet size in the order of 1μs has been concluded as a promising alternative for future OPS backbone networks. The switching architecture (switch fabric) is the node component responsible of the transfer of the optical packets from the input ports to the output ports of the switching node. This requires a packet-by-packet switching operation.

Optical Packet Switching: A Network Perspective

Abstract—In the last few years research on WDM optical packet-switching has mainly concentrated on issues at the single node level. The goal of this paper is to discuss about the problems arising when the focus is moved toward a network-wide scope. In particular, an overview of routing techniques that may be adopted in an optical packet-switched backbone is presented, showing the effects of adaptive multi-path routing strategies on the network performance.