Router Connections

Connecting a router to a network requires a router interface connector to be coupled with a cable connector. As you can see in the figure, Cisco routers support many different connector types.

Serial Connectors

Picture Router Connections

For WAN connections, Cisco routers support the EIA/TIA-232, EIA/TIA-449, V.35, X.21, and EIA/TIA-530 standards for serial connections, as shown. Memorizing these connection types is not important. Just know that a router has a DB-60 port that can support five different cabling standards. Because five different cable types are supported with thi

s port, the port is sometimes called a five-in-one serial port. The other end of the serial cable is fitted with a connector that is appropriate to one of the five possible standards.

Note: The documentation for the device to which you want to connect should indicate the standard for that device.

Newer routers support the smart serial interface that allows for more data to be forwarded across fewer cable pins. The serial end of the smart serial cable is a 26-pin connector. It is much smaller than the DB-60 connector used to connect to a five-in-one serial port. These transition cables support the same five serial standards and are available in either DTE or DCE configurations.

Note: For a thorough explanation of DTE and DCE, see Lab 1.5.1, "Cabling a Network and Basic Router Configuration."

These cable designations are only important to you when configuring your lab equipment to simulate a "real-world" environment. In a production setting, the cable type is determined for you by the WAN service you are using.

Ethernet Connectors

UTP CABLE

A different connector is used in an Ethernet-based LAN environment. An RJ-45 connector for the unshielded twisted-pair (UTP) cable is the most common connector used to connect LAN interfaces. At each end of an RJ-45 cable, you should be able to see eight colored strips, or pins. An Ethernet cable uses pins 1, 2, 3, and 6 for transmitting and receiving data.

DTE SERIAL

DTE SMART SERIAL

Two types of cables can be used with Ethernet LAN interfaces:
A straight-through, or patch cable, with the order of the colored pins the same on each end of the cable
A crossover cable, with pin 1 connected to pin 3, and pin 2 connected to pin 6

Straight-through cables are used for:
Switch-to-router
Switch-to-PC
Hub-to-PC
Hub-to-server

Crossover cables are used for:
Switch-to-switch
PC-to-PC
Switch-to-hub
Hub-to-hub
Router-to-router
Router-to-server

Note: Wireless connectivity is discussed in another course.
Related Topic Router

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