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An Ethernet cable is a type of network cable that is used to connect devices on a local area network (LAN), such as computers, routers, switches, and modems. Ethernet cables have RJ-45 connectors at both ends, which are similar to telephone jacks but larger. Ethernet cables can carry data signals at speeds ranging from 10 Mbps to 10 Gbps, depending on the type and quality of the cable. A cable modem is a device that connects to a coaxial cable from a cable service provider and provides high-speed internet access. A SOHO router is a small office/home office router that connects to a cable modem or DSL modem and provides network and internet access to multiple devices on a LAN. A SOHO router typically has one WAN port and four LAN ports.
The WAN port is used to connect to the cable modem or DSL modem, while the LAN ports are used to connect to computers or other devices on the LAN.
To connect a cable modem to a SOHO router, an Ethernet cable is needed. The Ethernet cable is plugged into the WAN port of the SOHO router and the Ethernet port of the cable modem. This allows the SOHO router to receive an IP address from the cable service provider and share it with the devices on the LAN using network address translation (NAT). The SOHO router also provides firewall and wireless features for the LAN.