1 HOMEPNA In June of 1998, was formed in U.S.A. the HomePNA trust (Home Phoneline Networking Alliance) between the companies 3Com, Agere Systems, AMD, AT& T Wireless Services, Broadcom, Compaq, Conexant, Hewlett-Packard, Intel, Motorola and 2Wire, among others. The trust launched in the market of technology of nets a challenge, the creation of a new technology for computer network using the existing telephonic cabeamento to pass through given, without intervening with the telephonic signal, this technology can be compared with technology ADSL (Assymmetric Digital Subscriber Line) or ' ' Anti-symmetrical Digital line for Assinante' ' , that it allows to the digital transference of data in high speed by means of common telephonic lines and simultaneous use of conventional telephony (Hisses, 2003). The structure of the wiring of the telephone inside of each locality originally is prepared to only take care of the signals of the conventional telephony, not existing the concern with insulation and marriage of impedances, that are the relation between the value efficient of the potential difference it enters the terminals in consideration to the efficient value of the resultant electric chain in a circuit. It indicates the total opposition that a circuit offers the chain flow alternated, or any another changeable chain in one given frequency. The topology of the telephonic net is generally a random connection of we 1.

The telephone, the fax and the modem can at any time be connected and be detached from the line, thus changing the topology of the net. In this set of telephonic wires where it will be mounted the net is possible to exist connection points that are not being used, this will be able to result problems in the transmission of the signal and many times in the echoes that can lead to the 2 signals multi-path. For these reasons, the assembly of a net using telephonic wiring for communication of data presents some challenges; as the main challenge can be cited the tolerance to the not specified and completely random topologies of net, therefore the structure of the telephonic handle it follows different routes or ways (DAYS, 2002).