A network cable looks very similar to a phone cable that is used in every home. You can easily differentiate between the two by the thickness of the cable. The phone cord is thinner and contains fewer wires or “pins” then a network cable. If you attempt to insert a network cable into a standard 56k modem it will not fit.
Network cables are used to connect PCs to an Ethernet network, which allows the computers to share information and resources. High-speed Internet connections use network cables. If you need to purchase a network cable for your internal network it is good to know that CAT-5 cable is the most commonly used type of network cable, and chances are this is what you need. Please consult the documentation that accompanies your high-speed modem to be sure.