Papers and Reports

Miscellaneous

  • The Effect of Ethernet Behavior on Networks using High-Performance Workstations and Servers.
    (Adobe PDF version - approx 96 KBytes).
    A technical report from Rich Seifert, one of the original designers of Ethernet, describing how Ethernets function in the presence of high offered load from powerful workstations. Includes a section on the Ethernet capture effect.

  • Issues in LAN Switching and Migration from a Shared LAN Environment.
    (Adobe PDF version - approx 519 KBytes).
    In this technical report Rich Seifert describes how switched Ethernets function and what issues to consider when planning to implement switched Ethernets at your site.

  • Usenet postings about Ethernet collisions. Two perennial questions about Ethernet are: What is a collision? and, What rate of collisions are acceptable? These questions are discussed in this set of Usenet postings.

  • What is SQE Test and When to Use It. The question: "What is the SQE Test signal and when should it be enabled on outboard transceivers?" is discussed in this document.

    Ethernet Performance

    When it comes to real-world network throughput, there are as many opinions about Ethernet performance as there are Ethernet installations. Every network site is unique, and the performance of the network is a function of the number of stations contending for access to the Ethernet, the type of hardware in use (station interfaces, switches), the layout of the cables (are they the right type, right length, and do they meet the config guidelines?), the quality of the cable installation, the mix of applications, and so on.

    The following items help demonstrate that an Ethernet LAN can transfer data at quite close to the nominal rated speed of the technology.

  • Measured Capacity of an Ethernet: Myths and Reality, by Boggs, Mogul, and Kent. From the abstract:"Based on measurements of an actual implementation, we show that for a wide class of applications, Ethernet is capable of carrying its nominal bandwidth of useful traffic, and allocates the bandwidth fairly. We discuss how implementations can achieve this performance, describe some problems that have arisen in existing implementations, and suggest ways to avoid future problems."

  • This posting from Van Jacobson from 1988 provides information about maximum Ethernet throughput rates for Sun workstations of that era.

    Ethernet Channel Capture

    Ethernet channel capture is a phenomenon in which the Ethernet media access control (MAC) system can become biased for a short term toward one station on a heavily loaded network. Under certain circumstances, this allows a station to more frequently win the contention for the channel, or ``capture'' the channel, while that station has something to send.

  • Usenet posting on Capture Effect. A short description of how capture effect works can be found in this Usenet posting from Rich Seifert.

  • A New Binary Logmarithmic Arbitration Method for Ethernet. A very complete description of channel capture which includes a solution based on modifying the Ethernet MAC is provided in this paper by Dr. Mart Molle. Note that some pages are missing from this file. The missing pages are composed of a set of full page figures that accompany the paper, which can be retrieved by clicking here:
  • Full page figures for Molle paper

  • Solving Capture in Switched Two-Node Ethernets by Changing Only One Node.
    This paper provides a further analysis of capture effect on two-node networks, and shows how the effect can be solved by changing the behavior of one of the nodes.

  • The Packet Starvation Effect in CSMA/CD LANs Part 1
  • The Packet Starvation Effect in CSMA/CD LANs Part 2 A paper on the "Packet Starvation Effect," and its effects on network latency for applications like packet video. "Packet starvation" is another way of describing the effects of Ethernet channel capture.

    Ethernet Chip Bugs

  • Performance Problems on High Utilization Ethernets A report from Xerox PARC that describes various problems with Ethernet throughput on high utilization coaxial cable networks.
  • Carrier Dropout on Coaxial Ethernets. The Xerox PARC report elicited a reply from an IEEE 802.3 committee engineer which described some known problems with coaxial Ethernet MAUs.
  • Ethernet Chip Bugs. Bob Metcalfe, the inventor of Ethernet, wrote several columns about the work at PARC including a survey of vendor responses to the Ethernet chip bugs.

    Ethernet Standard

  • Xerox Systems Institute Catalog. Version 2.0 of the original DIX Ethernet standard developed in 1982 by the DEC-Intel-Xerox consortium can still be ordered from Xerox. This standard was superseded in 1985 by the IEEE 802.3 standard.

    The IEEE 802.3 (Ethernet) standard can be obtained from an order fulfillment agent that handles requests for IEEE documents. One example is

  • Global Engineering Documents

    To retrieve an order form and instructions for ordering standards direct from the IEEE, send a message requesting help to the address: askieee@ieee.org, or call 1-800-949-IEEE or 1-415-259-5040. Members of the IEEE may be able to order from the IEEE at lower cost.

  • The IEEE also maintains an IEEE Web Page

    LAN Tech Scorecard

  • LAN Tech Scorecard A list of LAN technology standards.

    [ Home | Books About Ethernet ]