Cisco Systems 3700 specifications Cisco 3745 Interfaces, WAN and LAN Interface Numbering

Chapter 1 Overview of Cisco 3700 Series Routers

Interface Numbering

Cisco 3745 Interfaces

Each individual interface (port) on a Cisco 3745 router is identified by number as described in the following sections.

WAN and LAN Interface Numbering

The Cisco 3745 router chassis contains the following WAN and LAN interface types:

•Two built-in FastEthernet LAN interfaces

•Three slots in which you can install WAN or voice interface cards

•Four network module slots

The numbering format is interface-typeslot-number/interface-number. Two examples are:

•FastEthernet 0/0

•Serial 1/2

The slot numbers are as follows:

•0 for all built-in interfaces

•0 for all WIC interfaces

•1 for the lower-right network module slot

•2 for the lower-left network module slot

•3 for the upper-right network module slot

•4 for the upper-left network module slot

If double-wide network modules are installed, the network module slots are numbered as follows:

•2 for the lower double-wide slot

•4 for the upper double-wide slot

Interface (port) numbers begin at 0 for each interface type, and continue from right to left and from bottom to top.

Figure 1-4shows the rear panel of the Cisco 3745 with:

•A WIC in each of the three WAN interface card slots

•A single-wide network module in each of the four network module slots

•Two AC power supplies

The slot number for all WIC interfaces is always 0. (The W0, W1, and W2 slot designations are for physical slot identification only.) Interfaces in the WICs are numbered from right to left, starting with 0/0 for each interface type, regardless of which physical slot the WICs are installed in. Some examples are:

If physical slot W0 is empty and physical slot W1 contains a 1-port serial WIC, the serial interface in the WIC is numbered Serial 0/0.

If slot W0 contains a 2-port serial WIC and slot W1 contains a 1-port serial WIC, the serial interfaces in physical slot W0 are numbered Serial 0/0 and Serial 0/1, and the serial interface in physical slot W1 is numbered Serial 0/2.

If slot W0 contains a 2-port serial WIC and slot W1 contains a 1-port BRI WIC, the serial interfaces in physical slot W0 are numbered Serial 0/0 and Serial 0/1, and the BRI interface in physical slot W1 is numbered BRI 0/0.

Cisco 3700 Series Routers Hardware Installation Guide

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