Papers and Reports
Miscellaneous
Ethernet Reading List. A list of Ethernet
resources.
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. To retrieve
an order form and instructions, 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 direct from the IEEE at lower cost.
The IEEE also maintains an IEEE
Web Page
LAN Tech Scorecard
FTP Access to
LAN Tech Scorecard. Clicking here will retrieve the latest scorecard
from an anonymous FTP server at syr.edu. The list is stored on the
server as filename "lan-technology" in directory /information/faqs. Be
advised that the FTP access attempt may fail due to limits on the number
of simultaneous users allowed at the anonymous server.
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