Networking - Hardware - Cables

The first thing we need to discuss when looking at networking hardware is cables. This is networking at its most basic level but often overlooked since in recent years the choices of appropriate cables have been significantly simplified over previous years. Cables are however still very important as they determine how quickly data can move from computer A to computer B across your network.

To provide a more broad basis for our networking knowledge, we will start with some of the older cables that are almost completely unused and end with some of the currently most used cable standards. For the scope of this article we will leave out things like cable length limitations, but will define transmission speeds of various cable types.

Localtalk - Localtalk can be a little confusing but as it is almost completely unused anymore it shouldn't give you many problems. As localtalk is part of the Appletalk protocal, it is a protocal itself. However, localtalk also can refer to the cabling that was used at the time to transmit data across. Localtalk is a simple and extremely cheap cable. It is essentially the exact same type of cable used to connect a phone to the wall jack that one would find in your house. The transmission rate on localtalk cabling was limited to 256kbps, which for its day was quite spry. One drawback of localtalk that it required termination. If the cables were not properly temrinated, signals could bounce back through the lines when the reached the end of the daisy-chain. Daisy chaining localtalk connected computers was the only way to connect them save for some proprietary external controllers that allowed a star configuration.

Ethernet - Ethernet while still widely used today, has taken many forms over the years regarding the types of cables used to connect machines using it. All of these cable standards allowed speeds of 10Mpbs.

10Base-2 - 10Base-2 is coaxial cable. This is essentially the same type of cable that you would use to connect your televison to access cable tv. Like localtalk, computers using this type of cabling were daisy-chained and also required termination.

10Base-5 - This cable was in use much about the same time as 10Base-2, however it was much more expensive to deploy and more difficult to work with. Like 10Base-2, it was also coaxial cable, and required termination. However, it was also thicker and much heavier which unfortunately limited it to mostly "backbone" usage and smaller cables used for connecting to individual workstations. A big benefit of 10Base-5 was that it did not have to be daisy-chained, one needed only to tap into the cable to access the network.

10Base-T - This is what most people use for their smaller networks these days. In fact it is used so often that it is often just referred to as "ethernet cable" anymore. 10Base-T uses unshielded twisted pairs, in industry short hand you may see this referred to as UTP. This cable is most commonly seen as "Cat-5" which stands for category 5 which refers to the wirespeed that the cable is rated for. Cat-5 is rated for data speeds of more than 100Mbps where as the older Cat-3 is not suited for 100Mbps but works fine for 10Mbps data rates.

Fiber Optic - Fiber optic cable is a newer medium and is much more expensive in relation to copper wire based cables. These cables are long, narrow, strands of glass which transmit data using light instead of electrical pulses. Transcievers at the ends of this type of cable convert the lights pulses into electrical pulses to so that other device such as printers and workstations can utilize the signal. Fiber optics are most often use in very high speed and backbone network environments. Fiber optic cables utilize data rates of 1000Mbps (also known as a gigbit).