Specifications

2-14 Cisco Multiport Router Hardware Installation and Configuration Guide

Preparing to Connect to a Network

Figure 2-4 V.35 Serial Transition Cable Connectors, Network End

X.21 Connections

The X.21 connector uses a 15-pin connector for balanced circuits and is commonly used in

the United Kingdom to connect to the public data network. X.21 relocates some of the logic

functions to the DTE and DCE interfaces and, as a result, requires fewer circuits and a

smaller connector than EIA/TIA-232.

The network end of the X.21 serial transition cable (not included) is a standard DB-15

connector, as shown in Figure 2-5. The end that connects to the serial port on the rear panel

of the router has a DB-60 connector. X.21 cables are available with a plug or receptacle in

either DTE or DCE mode. To order a cable, see the section “Obtaining Service and

Support” in the “Overview of the Router” chapter.

Figure 2-5 X.21 Serial Transition Cable Connectors, Network End

H1616a

DTE

DCE

DTE

H1346a