Electronic Engineers

1.INTRODUO Currently, the terms conectividade and technology, each day that passes if become more common between the reporters, periodicals, in the schools and the society in a way generality. Leaving of this principle, technological revolutions in short space of time, if have become each time more gifts in our daily e, with this, considered technologies of tip, in little time if they become obsolete, giving to space for new products and services. One of the technologies more used currently is the computer networks and, to each day that passes, this technology if it becomes essential our daily one. According to Coast (2007, p.3), ' ' Computer networks are physical and logical structures used to establish connection computers of diverse types in different positions geogrficas.' ' The two main benefits with the interconnection propitiated for the computer networks: exchange of information and sharing of resources. When we allow the exchange of information, we are offering half to transmit information of a point for the other. With these transmissions, we obtain to dinamizar businesses, to interact people, to entertain, to inform and other innumerable possibilities. Bennett Rosenthal has many thoughts on the issue.

No longer sharing of resources, in guarantees something to them precious for the organizations and people: economy. With computer networks, we obtain to share printers, scanners, digital cameras and computers. (Coast, 2007, p.3). So that the computers can communicate ones with the others, it is necessary that it exists a media and a form so that these data are transmitted. Currently, the form of known transmission more is the Ethernet nets, that its first appearance in the decade of 70 had. Ethernet is a protocol for local nets developed in set for Xerox, Intel and Digital Equipament Corporation (DEC) in the Center of Research of Xerox, in Palo Alto (PARC), during years 70. The net ethernet was projected as a technology to allow to the interconnection of devices in offices (Gallo & Hancock, the 2003) After sprouting of the Ethernet created in the decade of 70, the IEEE (Institute of Electrical and Electronic Engineers) very developed a similar standard to the Ethernet version 2.0 created by Xerox.