A very important point - of the factors affecting the choice of physical medium (cable system). Among them are the following:
1) The required capacity, speed transmission network;
2) The size of the network;
3) The required set of services (data, voice, multimedia, etc.), which should be organized.
4) the level of noise and pomehozaschischennosti;
5) The total project cost, including purchase of equipment, installation and subsequent operation.
The main data Wednesday LKS - unshielded twisted pair, coaxial cable, multiple fiber. With approximately the same value of single-and multi-fiber, terminal equipment for a single considerably more expensive, while providing long-distance. Therefore, the LCS used mostly multiple optics.
Key technology LKS: Ethernet, ATM. Technology FDDI (2 rings), used previously to supporting networks and having a good performance in the distance, speed and reliability, now little used, largely because of high costs, as did technology and ring Token Ring, although both of them before still maintains a high level all the leading vendor, and in some cases (such as the use of FDDI for the backbone network scale of the city, where needed high reliability and guaranteed delivery of packages) use of these technologies may still be warranted.