Cat 5 is also used to carry other signals such as telephone and video. This cable is commonly connected using punch-down blocks and modular connectors. Most Category 5 cables are unshielded, relying on the balanced line twisted pair design and differential signaling for noise suppression.OverviewCategory 5 cable (Cat 5) is a cable for. Since 2001, the variant commonly in use is the Category 5e specification (Cat 5e). The cable standard provides performance of up to 100 MH. Category 5 is currently defined in, and EN 50173, though it was originally defined in / (with clarification in TSB-95). These documents specify performance characterist. The Category 5e specification improves upon the Category 5 specification by further mitigating. The (100 MHz) and physical construction are the same between the two, and most Cat 5 cables actu.