This is a SWITCH not a router. You need a router to communicate with your Internet Service Provider (ISP) like Comcast, Fios, Cox, etc. You can buy a Cable Modem from BestBuy or another source instead of renting one through your ISP. If you need more than the supplied connections on the router (usually 4 Ethernet jacks) you can add this switch to add more ports/jacks/connections.
Keep in mind, if your on cable and you buy a cable modem, and have more than one device hooking up (usually) you need to purchase a cable modem WITH WIFI or a cable modem and a Wifi Router (same thing like a switch, however it manages devices, adds wifi and is needed prior to a switch)
Hope this helps....
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