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Name: Ryan
Status: Student
Age: 15
Location: N/A
Country: N/A
Date: June 2002


Question:
Two computers in are house share a DSL line that split with a hub or a router (I forgot which one it is). One of the computers "mine" keeps getting disconnected from the Internet but the other one does not. The only way to get it to connect again is to either restart or go in to standby mode which is what i do. then 5 minutes later it disconnects me again. Also whenever I am downloading something it disconnects me more often. This gets really frustrating. I checked everything to make sure its working right and everything seemed fine to me so I am guessing that it is my computer. It could not be the hub, the cord, etc. because the other computer is working just fine. So, can anybody think of anything that could be wrong with my computer that keeps causing me to get disconnected?



Replies:
Ryan this is a great question.

First I would like to eliminate some variables here to make sure you are going in the right direction when it comes to your troubleshooting. First have you connected the computer that keeps getting disconnected directly to your DSL modem and if so does it still get disconnected? If your computer does not get disconnected then you know it is not the computer but somewhere in the upstream process that is causing your communication failure. I am also assuming that you are using a DLS router to split the signal, (ie a Linksys) did you check their web site to make sure there are no known issues with that router disconnecting people from the Internet? What DSL provider are you using? Some DSL providers use an encapsulating technology called PPPOE (Point to Point Protocol over Ethernet) which require you to scale back your MTU (Maximum Transmission Unit) to work properly with their system when using multiple computers over one DSL line. If your computer is sending multiple packets of data and they are over this maximum of 1500 bytes then your computer will seem to lose connection. I have seen routers turn off that port for a given number of minutes to ensure that the computer is not flooding the network with garbage packets if it detects the MTU is larger than 1500 bytes. As a last resort, try to reset your router. Turn it off wait 5 minutes and then turn it back on.

Here is a great web site that has all of the information you need to help you in your DSL troubles and give you information on how to change your MTU.

http://www.speedguide.net

I hope this gives you a place to start in your troubleshooting quest.

Thanks For using NEWTON.
Joe Noga


There are no doubt people on Newton BBS far more expert than I who may know the answer. If not there are several ways to find resources: 1. The web site www.deja.com is a "chat room" type site where people post question/solution type questions. Post your problem and see what responses have already been posted. Look for the response that shows the largest number of "hits". That is where you will most likely find the answer. Magazines like "P.C. World" have web pages with FAQ's that may also lead you to a solution. Check with your Internet provider, it may be that the settings on the "bad" computer are not correct.

Vince Calder


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