This is, as I suspected, all you need - and replaces the modem.
You can connect your systems to it via wired LAN or wireless LAN.
Your systems need an Ethernet port, or a wireless facility. Most recent systems already have a LAN port (and most recent laptops/netbooks) have wireless). If you need a card or such in your existing system to give you a LAN port - let us know what type of system you've got.
Then the router connects to your ADSL line directly.
It may just work right away. If not ask again.
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