CertiGuide to Network+  9  Chapter 0001:  LAN Cabling

VIII  Wireless Networking 1 X  Real-World LAN Cabling

The first networks were very small by today’s standards and were used to connect a few mini or mainframe computers. As the viability of networks became field proven and costs became lower, PC based computers were added to networking.

This gave rise to not only increased network traffic, but also a need to logically handle traffic load. The concept of segmenting came into being, to address the issue of traffic load, minimizing the amount of unnecessary traffic that flows across parts of the network. (Remember that in Chapter 0000, we discussed the use of LAN segments to manage network traffic, to keep high-traffic communication partners from slowing down the rest of the network).

The idea is to give the greater and faster bandwidth to larger traffic areas, while using slower and less expensive methods for network traffic with lower needs. The model is akin to the highway system in the USA. Major freeways connect cities, while surface streets carry less traffic at slower speeds.

Today, fiber optic cabling is frequently is used to act as the ‘digital freeway’ with UTP (Unshielded Twisted Pair) for local traffic. Older digital highways used the legacy 10Base5 (Thicknet) for connections. This is because this larger cable allowed for longer distances to be traveled.

So, you can see that planning your network cabling does not involve an all-or-nothing choice. Different types of cable (and wireless technology) can be mixed, through the use of additional network hardware that converts the signals to and from the different physical transmission media.

You might be wondering now, given the descriptions of connectors on all these types of cable, and different data transmission speeds, how the different types of physical media can pass data back and forth to and from each other. Special network devices such as bridges are used to connect two separate segments of a network, which may be based on the same type of cable (such as two Thicknet segments) or completely different technologies (such as a Thicknet segment and a Thinnet segment). A router with the appropriate connectors on it can also be used to connect network segments based on different technologies, although it’s not the primary purpose of a router. You’ll hear more about bridges, routers and other specialized network devices later in this course.

VIII  Wireless Networking 1 X  Real-World LAN Cabling