Thin Ethernet Cable Notes
This document contains cabling and installation recommendations. For
more information on thin Ethernet cabling, contact your local network
supplier or call the IEEE at 800-678-IEEE.
The EtherExpress adapters have a cylindrical, bayonet BNC connector.
BNC cabling is also known as thin Ethernet, RG-58A/U, Cheapernet, and
10BASE-2.
Recommended Cables
Here is a list of IEEE approved and non-approved cables.
Approved cable types | |
802.3 10Base2 | 50 ohms, stranded tinned core |
RG-58 a/u | 50 ohms, stranded tinned core |
RG-58 c/u | 50 ohms, stranded tinned core |
NON-Approved cable types | |
RG-58 | 50 ohms, solid center core |
RG-58 u | 50 ohms, solid center core |
Installation recommendations
Thin Ethernet is a linear bus toplogy that uses a coax cable. A break
in tcable will disrupt the entire segment.
Each node is connected to the cable using a T-connector.
- Don't connect the end of the cable directly to the BNC connector on
the EtherExpress card.
- Do not use cable drops or external transceivers unless you are
using the AUI connector instead of the BNC connector.
Both ends of a trunk must be terminated with 50 ohm terminators. One
end should be grounded.
Up to 5 trunk segments may be connected (through repeaters), but only
three of these segments can have workstations attached. Repeaters count
as a workstation. If you have two repeaters on a segment, then the
maximum number of user workstations is 28.
Example:
no workstations no workstations
| |
v v
|--+------+ +--------+ +-----+------+ +--------+ +----+----|
| | | | | | | | | | |
| repeater repeater | repeater repeater |
| | |
workstation workstation workstation
1-29 1-28 1-29
Cable Lengths | |
Max trunk length | 185 meters (607 feet) |
Max number of nodes per trunk | 30 |
Max number of trunks | 5 (only 3 can have wkst attached) |
Max length of entire network | 925 meters (3035 feet |
(all trunks added together) | |
| .5 meters (1 1/2 feet) |