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A major part of implementing a network involves the installation of a cabling system. A solid cabling system is a good investment that will not only meet your current networking needs, but will last through your next-generation network as well.

All modern Ethernet networks follow a star topology, where each device on the network connects with its own cable to a hub or some other device. If your network is contained in a single room, then you can simply use drop cables to connect each device on your network to a hub. If your network spans an entire building, then you will need to install a cabling system, and designate one or more wiring centers for your network. Cables originate at the location of each device on the network and terminate in a wiring center. On the user end, the cable will terminate with a wallplate and in the wiring center the cable will terminate in a jack on a patch panel. To ensure that your network will work not only for your current needs, but in the future, be sure to use high-quality cables that conform to well-established standards.

In the current environment there are basically three options for connecting computers: copper wire, fiber optics and wireless technologies.

Fiber optics work very well in enterprise networks as a backbone infrastructure. Fiber offers exceptional performance for high-bandwidth applications, and is extremely reliable and secure. Fiber is not susceptible to many of the sources of interference that can play havoc with copper-based cabling systems. Fiber is also considered to be more secure since it cannot be tapped unless you cut and splice the fiber strands-a task that is virtually impossible to accomplish without detection. If you need to connect a set of buildings within a corporate complex or academic campus, then fiber optics offer the very best solution.

While it is possible to use fiber optics to connect PCs and printers in a LAN, only organizations with serious security concerns and extremely data-intensive applications regularly do so. Fiber-optic networks are expensive to implement, and their installation and maintenance demand a higher level of expertise. At a time when we can achieve 100 Mbps speed over copper cabling, it is seldom cost-effective to use fiber optics for a small office network.

Another alternative for LAN communications involves wireless technologies. By installing a wireless hub and transmitters on each computer, you can build a LAN without installing cabling at all. The cost of the wireless equipment can, in some cases, be less than the costs of deploying a cabling system, especially in buildings that lack the drop ceilings, cable trays and natural pathways needed for easy cable installation. The flexibility of moving computers around without having to deal with cable issues is another benefit. In most cases, however, cable installation costs less than putting wireless equipment in place. Wireless networks also offer less performance than cable-based alternatives. Most wireless networks on the market now operate at about 2 Mbps-roughly one fifth the bandwidth available through standard 10Base-T Ethernet, and a much smaller fraction of 100Base-T. Wireless LANs continue to be appropriate for a niche of environments where cabling issues are difficult and mobility is required. But the typical small office network will be better served by a traditional copper-based cabling system.

Most LANs are based on unshielded twisted pair (UTP) copper cabling. This cabling is relatively inexpensive and can support a great variety of network types. Most UTP cables include four pairs of copper wire, where pairs of individual wires are twisted together and the four pairs are then twisted. The quality of the wire and the number of twists determine the electrical characteristics of the cable. Properly twisted cable will be less susceptible to interference and will support high data throughput. The current standard for data cable for 10Base-T and 100Base-T networks is Category Five. Some cable installers will have Category Five-Plus or Category Six cable available. Given that the labor costs for installation are much higher than the material cost for cable, use the highest grade available. Be sure also that all jacks, connectors and patch cords involved are of the highest quality.

Should you install the cabling yourself, or hire a contractor? The smaller the office network, the more tempting it is to install cabling in-house instead of hiring professional cable installers. This will save some on installation costs, but it is important to be sure that all the cabling is installed and tested to professional standards. If your network fits within a room, then it is usually no problem to hook up the cables between the hubs. But if your network encompasses multiple rooms-especially if it is spread among multiple floors-then seriously consider hiring a professional cable installer. Make sure that the cable installer you select has specific experience with data communications networks. General electricians may not be familiar with all the requirements. An experienced data communications cable installer will know the specific grades of cables to use, will use the right connectors and will have the equipment to test the cabling system's ability to meet specifications.