Four-Wire Crossover Cable Rj45 Pinouts For 10/100Base-Tx - Enterasys C2K122-24 Hardware Installation Manual

3. Verify that a link exists by checking that the Link/Activity LED is ON (solid green or
blinking green). If the Link/Activity LED is OFF, perform the following steps until it is
on:
a. Verify that the cabling being used is Category 5 or better with an impedance
between 85 and 111 ohms with a maximum length of 100 meters (328 feet).
b. Verify that the device at the other end of the twisted pair segment is on and
properly connected to the segment.
c. Verify that the RJ45 connectors on the twisted pair segment have the proper
pinouts and check the cable for continuity. Typically, a crossover cable is used
between hub devices. A straight‐through cable is used to connect between
switches or hub devices and an end user (computer). Refer to Figure
Figure 3‐14 for four‐wire RJ45 connections. Refer to Figure 3‐15 and Figure
for eight‐wire RJ45 connections.
d. Ensure that the twisted pair connection meets the dB loss and cable specifications
outlined in the Cabling Guide. Refer to "Related Documents" on page xvi for
information on obtaining this document.
4. If a link is not established, contact Enterasys Networks. Refer to "Getting Help" on
page 1‐5 for details.
Repeat all steps above until all connections have been made.
Figure 3-13

Four-Wire Crossover Cable RJ45 Pinouts for 10/100BASE-TX

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1 RJ45 switch port
2 Other device port
À
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3 RJ45-to-RJ45 crossover cable
4 RX+/RX- and TX+/TX-connections
These connections must share a common color pair.
Connecting to the Network
3‐13 and
Á
SecureStack C2 Installation Guide 3-21
3‐16