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Router physical characteristics / Router external connections

Router physical characteristics
1.2.2 This page will help students identify the location of different components on a router.


It is not critical to know the location of the physical components inside the router to understand how to use the router. However in some situations, such as adding memory, it can be very helpful.

The exact components used and their location varies between router models. Figure identifies the internal components of a 2600 router.

Figure shows some of the external connectors on a 2600 router.

The next page will describe the external connections on a router.

Router external connections
1.2.3 This page will describe the three basic types of connections on a router, which are LAN interfaces, WAN interfaces, and management ports.


LAN interfaces allow routers to connect to the LAN media. This is usually some form of Ethernet. However, it could be some other LAN technology such as Token Ring or FDDI.

WANs provide connections through a service provider to a distant site or to the Internet. These may be serial connections or any number of other WAN interfaces. With some types of WAN interfaces, an external device such as a CSU is required to connect the router to the local connection of the service provider. With other types of WAN connections, the router may be directly connected to the service provider.

The function of management ports is different from the other connections. The LAN and WAN connections provide network connections through which packets are forwarded. The management port provides a text-based connection for the configuration and troubleshooting of the router. The common management interfaces are the console and auxiliary ports. These are EIA-232 asynchronous serial ports. They are connected to a communications port on a computer. The computer must run a terminal emulation program to provide a text-based session with the router. Through this session the network administrator can manage the device.

The next page will provide a detailed explanation of management ports.

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