• United States

Sharing a single DSL line between two computers

Oct 07, 20022 mins

Ron Nutter helps a user who wants to share his DSL connection between two computers.

Can I use a hub to share a single DSL line between two computers or is it better to buy a router? How does the hub actually work? To my understanding the hub doesn’t do any filtering, so will I be getting packets destined for the other computer as well?– Via the Internet

You can use a hub to share  DSL between two or more computers, but you will need to make sure that falls within your ISP’s acceptable use policy and terms of service.  There is a danger in this approach in that it will leave your machines exposed to the outside world and require that you install additional software in the form of a software firewall to lessen the chance that someone will hack the machines.  You are correct in saying a hub won’t do any filtering.

If you want to route specific traffic from the outside to a computer on your DSL connection, purchasing a DSL router is the best way to go.  You will need to decide what type of traffic you want to route to which machine.  If you will have different types of traffic going to each machine (i.e., http – Port 80 – to one system and SMTP/POP – Ports 25 and 110 – to the other, you can look for a router that will do port address translation (PAT).  If you will have, for example, http traffic going to both systems, you will need to find a router that will do network address translation and have the ISP assign you two public IP addresses.  The router will then take requests for the first address and route all traffic to the first machine, and all traffic for the second address to the second machine.

When doing any type of services in which requests will be coming from outside your network, make sure that you are in compliance with your ISP’s terms of service or you could find yourself without a connection.  Also, look at the speed your line is rated for.  Different providers provision DSL differently; some have the same upload and download speeds, others use one speed for upload (traffic leaving your network) and another speed for downloads (traffic coming into your network). Ensure that your line can handle the type of traffic you’re planning to handle.