A gigabit network requires that every part of the network must be gigabit-capable, while it will run at the speed of the lowest common denominator. For example, if you’re running a network with gigabit network cards and gigabit-compatible cables, but your hub/switch is only capable of 100 megabit transfers, then your network will run at 100 megabit speeds.
The first prerequisite is the network controller. You'll probably want every computer on the network to have a gigabit-capable network card or motherboard-down solution. This is probably one of the easiest requirements to meet, as most motherboards manufactured during the past couple of years have gigabit networking built right in.
The second prerequisite is that the network cable must also be gigabit-compatible. There is a common misconception out there that gigabit networks require Category 5e class cable, but actually, even the older Cat 5 cable is gigabit-capable. Having said that, Cat 5e cable has better electromagnetic interference characteristics and is therefore a better choice for gigabit networking, especially when using longer cable lengths. Frankly, Cat 5e cable is probably the cheapest cable you’ll find available today, as the older Cat 5 is obsolete. The newer and more expensive Cat 6 cable is also more than certified for gigabit applications. We'll be testing Cat 5e versus Cat 6 cable performance later in the article, just to be sure.
The third, and probably the most expensive component in a gigabit network, is a gigabit-capable hub. Of course, a switch or router would be preferable, since a hub is a somewhat "dumb" device that shares all of the network traffic bandwidth at every one of its ports, which can cause a lot of data collisions and, therefore, slower network speeds. A gigabit switch should be the minimum requirement for someone interested in network performance, as it directs network packets to the proper port, resulting in increased speed compared to a hub. A router is also preferable over a hub as it is capable of switching, in addition to connecting your LAN to the Internet. Most folks running a LAN at home will probably realize the benefits of a router anyway, so a gigabit router is an attractive option.