Optical Fibre LAN Research Articles

Performance Analysis for a Novel Ring Network System

A novel optical fiber LAN network with ring topology is proposed in this paper. It is possible for users in this network to communicate with each other. In order to evaluate the system performance, the multiple-access interference (MAI), the self-interference, and the channel noises are considered, and then, the analysis of system performance is carried out. The results show that the near-far effect exists, and there is an optimum number of users. In order to solve this problem, the transmitted power of users should be controlled.

Code-division multiple-access in an optical fiber LAN with amplified bus topology: the SLIM bus

A novel optical fiber network with a bus topology and dark signaling (the SLIM bus) using optical code-division multiple-access (CDMA) is proposed. With a new design of delay line correlator the network is shown to eliminate optical beating noise and overcome the main limitations of incoherent optical CDMA in a star topology.

Performance evaluation of FDDI under asymmetric traffic conditions

FDDI is a proposed standard for optical fibre LANs. A simulation model is used to examine the performance of the FDDI protocol under asymmetric traffic conditions. The relationship between the average token rotation time and the relative stability of the network is also presented.

Optical coherent systems in optical fibre LAN's and MAN's

A review of the potentialities offered by optical coherent techniques in LAN's and MAN's applications is presented. Some aspects concerning both topology and access techniques have been briefly discussed. The optical coherent systems and their technological requirements have been analyzed in order to show the advantages offered both in networking and broadcasting.

Protocols for multichannel optical fibre LAN using passive star topology

Multiple access protocols for a multichannel optical fibre LAN using a passive star topology are discussed. Of the available channels one is used to transmit control packets and the remaining channels are used to transmit data packets. The protocols use the slotted Aloha for the transmission of control packets which identify their intended receiver address. They work independently of the propagation time of the network and achieve higher throughput than comparable protocols proposed in the literature.

Wavelength division multiple access on a high-speed optical fibre LAN

Abstract A multichannel medium access control protocol suitable for implementation on a wavelength division multiplexed optical fibre LAN is discussed. Particular emphasis is placed on the mean delay against network throughput performance at individual channel transmission rates of 100 Mbit/s. The protocol is based on a token passing arbitration policy which dynamically allocates both the token and the data to individual wavelength multiplexed channels. An improved performance is demonstrated in comparison with alternative conventional approaches operating at an equivalent overall network transmission rate.

Orthogonal codes for CDMA optical fibre LANs with variable bit interval

Recently proposed optical orthogonal codes (OOC) require strict control of both chip interval and bit interval of all the transmitters in a LAN. The strict bit interval control requirement can be eliminated if an additional constraint is introduced in the OOC design. The definition of an optimal OOC is introduced and some algorithms for low weight optimal OOC design are proposed.

Technology '90: data communications

The growing use of local area networks during 1989 is examined. The fiber distributed data interface (FDDI), a 100 Mb/s dual-ring, optical fiber LAN that is nearing approval by the American National Standards Institute, is discussed. Other developments reviewed are the increasing support for the Internet Transmission Control Protocol/Internet Protocol, setbacks in promoting the OSI (open systems interconnection) approach due mainly to the scarcity of products and weak sales, work on ways to bridge the two sets of protocols, and the emergence of high-speed networking as a viable technology. >

Design and performance evaluation of an optical fibre LAN with double token rings

The Deterministic Access Fibre Network, an optical fibre local area network which aims to offer a set of services including data transmission, sound and images, is presented. The topology is of the ring type, on which there are active nodes based on the International Organization for Standardization Open Systems Interconnection architecture, with access complying with the IEEE 802.5 token-ring standard. To increase throughput, and to make the network highly reliable, a two-fibre cable forming two counter-rotating rings is installed. First, the hardware and software architecture adopted for a typical DAFNE node is discussed, then a methodology to aid the designer in choosing the optimal LAN configuration according to the user's needs by a highly interactive and automated environment is outlined. Finally, analytical and simulation approaches are shown for performance evaluation of the Medium Access Control layer.

Performance investigation of a token passing access protocol for a multichannel optical fibre LAN

An alternative approach to multichannel local area network access is described. The new multichannel access scheme or protocol is based on a token passing arbitration policy. It is specifically intended for use with a starconfigured optical fibre LAN employing wavelength division multiplexing technology in order to provide a multichannel transmission medium. The multichannel network architecture comprises a single reservation channel and several equivalent speed data channels. Delay versus throughput performance characteristics for the network obtained by both analysis and discrete event simulation are shown. The multichannel token passing protocol is found to significantly improve these characteristics in comparison with a conventional single channel token passing approach using the same overall network transmission rate (i.e. the sum of the individual channel bit rates in the multichannel case). Furthermore, when the end-to-end propagation delay for an individual channel on the network becomes large, the multichannel token passing protocol is shown to exhibit an improved delay versus throughput performance over a multichannel protocol employing carrier sense multiple access with collision detection.

Optical fibre LANs for mixed data traffic

This paper begins with a short review of the implications of using optical fibre communications technology for LANs. Traffic characteristics and the access requirements of a wide range of devices are then described, followed by the consideration of channel access protocols for optical fibre LANs. A novel, adaptive, hybrid token passing-CSMA/CD protocol designed for use with an optical fibre LAN serving a mixed data traffic environment is discussed. Its performance is compared with that of a purely token-passing protocol, demonstrating a significant improvement for the hybrid with both symmetrically and asymmetrically distributed traffic loads.

Topology and MAC layer access protocol investigation for industrial optical fibre LANs

The application of optical fibre communications technology is advocated for LANs to be employed within an industrial environment. Attributes and drawbacks associated with possible topologies for optical fibre LANs are discussed, and reasons are advanced for the use of a multiple star topology for industrial LANs. Consideration is then given to the use of MAC layer access protocols with industrial traffic, including probable asymmetric traffic loads. A novel adaptive hybrid token-passing CSMA/CD access protocol is suggested for use with a passive star-based industrial optical fibre LAN. Operating details of the hybrid protocol are described together with its computer simulated performance characteristics. In this way, the novel hybrid protocol is shown to perform efficiently with both symmetric and asymmetric traffic load distributions.