This document explains the Ethernet AUI port, the cabling specifications, and the port pinouts.
There are no specific requirements for this document.
The information in this document is based on the software and hardware versions:
AUI adapter cable: CAB-3CE18=
The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.
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For flexibility, some Cisco routers provide a generic AUI connector for Ethernet ports. These AUI ports are designed to connect to an external transceiver for conversion to a specific media type (such as twisted pair, coax, or fiber). The transceiver may either be directly connected to the AUI port or through an AUI Cable as illustrated below:
This section explains the Ethernet port and cable specifications.
The table below lists the different pins and their appropriate signals.
|3||DO-A||Data Out Circuit A|
|10||DO-B||Data Out Circuit B|
|11||DO-S||Data Out Circuit Shield|
|5||DI-A||Data In Circuit A|
|12||DI-B||Data In Circuit B|
|4||DI-S||Data In Circuit Shield|
|2||CI-A||Control In Circuit A|
|9||CI-B||Control In Circuit B|
|1||CI-S||Control In Circuit Shield|
|14||VS||Voltage Shield (L25 and M25)|
1Any pin not referenced is not connected.
The table below lists the Ethernet Version 2 and IEEE 802.3 physical characteristics of the Ethernet cable.
|Data rate (Mbps)||10||10||10||10|
|Maximum segment length (in meters)||500||500||185||100 (Unshielded twisted pair - UTP)|
|Media||50-ohm coax (thick)||50-ohm coax (thick)||50-ohm coax (thin)||UTP|
The following table lists the Ethernet coaxial-type connection limits for 10-Mbps transmission.
|Cable diameter||1 cm (0.4 in)||0.6 cm (0.25 in)|
|Maximum segment length||500 m (1640 ft.)||152 m (500 ft.)|
|Maximum network length (with four repeaters)||2500 m (8200 ft.)||762 m (2500 ft.)|
|Maximum connections (taps per segment)||100||30|
|Minimum connection (tap) spacing||2.5 m (8.2 ft.)||0.5 m (1.64 ft.)|
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Refer to Cisco Technical Tips Conventions for information on conventions used in this document.