Round Ethernet cables have a round structure and come with full shielding. This filler material also provides the network cable with protection against friction-induced heat and impact from the outside. When setting up a new network in your home or office, you'll use internet cables to connect a router or a modem to your PC. These cables are known as Ethernet cables. You're probably already familiar with various types of Ethernet cables, such as CAT5, CAT6, CAT6a, or CAT7, but you might not know. The round Ethernet cable is the industry standard for a reason. Inside its typically thick, durable PVC jacket, you'll find four twisted pairs of copper wires.