Table Of Contents
Ethernet Network Cabling Guidelines
Cabling Specifications
This appendix describes cables and cabling guidelines for the Cisco 1721 router and contains the following sections:
•
Ethernet Network Cabling Guidelines
Note
Ethernet Cables
This section describes the Ethernet cables that are used to connect the router to your local Ethernet network. A 10/100BASE-TX router, such as the Cisco 1721 router, requires Category 5 unshielded twisted-pair (UTP) or shielded twisted-pair (STP) cable. Table B-1 gives the pinouts for an Ethernet cable.
Table B-1 Ethernet Cable Pinouts
Pin1
Pin1
TX+
—>
1
2
TX-
—>
2
3
RX+
<—
3
6
RX-
<—
6
1 Pins 4, 5, 7, and 8 are not used for signaling.
Ethernet Network Cabling Guidelines
Table B-2 describes some guidelines for creating Ethernet networks. Figures might vary, depending on the manufacturer of the network equipment.
Table B-2 Ethernet Cabling Guidelines
Maximum segment length
100 meters
100 meters
Maximum number of segments per network
5
•
•
Maximum hop count1
4
•
•
Maximum number of nodes per segment
1024
1024
Cable type required
UTP
Category 3, 4, or 5UTP Category 5 or STP
1 Hop count = Routing metric used to measure the distance between a source and a destination.
Console Cable and Adapter
A console cable is provided with your router. Use this cable to connect the router to a PC or terminal. The router comes with a DB-9-to-DB-25 adapter that may be used for connecting the router to a modem, using the console cable.
Table B-3 describes the wiring for the console port and the console cable. This table also includes pinouts for the DB-9-to-DB-25 adapter.
