Network Representations

Diagrams of networks often use symbols, like those shown in Figure 1, to represent the different devices and connections that make up a network. A diagram provides an easy way to understand how devices in a large network are connected. This type of “picture” of a network is known as a topology diagram. The ability to recognize the logical representations of the physical networking components is critical to being able to visualize the organization and operation of a network.
In addition to these representations, specialized terminology is used when discussing how each of these devices and media connect to each other. Important terms to remember are:

• Network Interface Card - A NIC, or LAN adapter, provides the physical connection to the network at the PC or other end device. The media that are connecting the PC to the networking device, plug directly into the NIC (Figure 2).

• Physical Port - A connector or outlet on a networking device where the media is connected to an end device or another networking device.

• Interface - Specialized ports on a networking device that connect to individual networks. Because routers are used to interconnect networks, the ports on a router are referred to as network interfaces.

Note: Often, the terms port and interface are used interchangeably.