Specifications

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Cisco 7100 Series VPN Router Installation and Configuration Guide
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Chapter 3 Installing a Cisco 7100 VPN Series Router
Connecting to the Network
Figure 3-10 Connecting the T1 WAN Serial Ports on the Cisco 7120-4T1 or Cisco 7140-8T
Caution Serial interface cables must be attached correctly or damage to the cable plug will result. Attempting to
force a cable plug on the 60-pin receptacle can damage the plug. (See Appendix C, “Cable
Specifications,” for additional information.)
Note For more information, see the “Cisco 7120-4T1 and Cisco 7140-8T Cables and Pinouts” section on
page C-5.
Connecting the Cisco 7120-T3, Cisco 7120-E3, Cisco 7140-2T3, and
Cisco 7140-2E3
Use a 75-ohm coaxial cable to connect your router to a T3 or E3 serial network. Serial cables conform
to EIA/TIA-612 and EIA/TIA-613 specifications. The T3 or E3 serial ports on the router are considered
to be DTE devices.
The Cisco 7100 T3 and E3 models have the following port configurations:
• Cisco 7120-T3—One T3 serial port
• Cisco 7120-E3—One E3 serial port
• Cisco 7140-2T3—Two T3 serial ports
• Cisco 7140-2E3—Two E3 serial ports
Each T3 or E3 serial port has two connectors (receive and transmit), where you connect the
Cisco 75-ohm coaxial cable. The 75-ohm coaxial cable (Cisco product number CAB-ATM-DS3/E3) is
available only from Cisco Systems; it is not available from outside commercial cable vendors.
To CSU, DSU, or external
synchronous serial equipment
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