In addition to a router, you need a straight-through cable for each computer you want to connect to the network.
Cable/DSL modem
Router
WAN port
To set up a network using a router:
1Plug one end of the power adapter into the AC connector on the router and the other end into a grounded, 110V electrical outlet.
2Turn on your computers.
3Plug one end of a straight-through network cable into any numbered port on the router (except the WAN port). The WAN port is used to connect the router to the DSL or cable modem and is identified by a label or a switch. Plug the other end of the cable into the network jack on the computer. As each computer is connected to the router, the corresponding green indicator should light on the front of the router, indicating a good connection.
4Repeat 3 for each computer on the network.
5For an Internet connection, plug a straight-through cable into the WAN port on the router and the other end into the Ethernet jack on the DSL or cable modem.