Maximun LAN cable length supported By DSL modem

We are often confused about this, that what maximum length is supported by DSL broadband technology. Actually, it depend on DSL modem that we will use. Most of the DSL modem provided by our ISP like Airtel , BSNL, MTNL support upto 20 meter. But it can be more and less depending on modem support.

I got my first DSL broadband, in year 2005 from Airtel Broadband. First thing, I tried to do after getting new connection is sharing internet connection with my friend in my hostal. I had to share internet among 3 computers. One was mine own, and two friend's computer. We bought LAN cable and crimped in straight. One LAN cable was of 10 meter, and second was of 25 meter. My computer was near modem, So, I used 1 meter LAN cable provided by Airtel.

But, the system connected with 10 meter wire was able to surf internet, but system with 25 meter LAN wire was not able to surf internet. So, we though that 25 meter LAN wire has some problem. I took the wire to a nearest shop for check, but found that wire was correctly crimped, and was working there.

Than I did some Google search, and found that yes length do matter. Than, we took a HUB, and did sharing with HUB. We created star topology network. And yes, the system on 25 meter LAN wire was able to surf internet with no problem. So, we can increases the lenght of LAN wire supported by DSL modem by using HUB or switch or router. But again length will depend on Hub/ Switch / Router that we will use.