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I'm currently having issue on a ADSL connection regarding performance. During the evenings, around 18h00, up until at least 01h00 the connection speed drops down from the +- 600 kb/s (6ish mbit) to a poor 10-150kb/s. (depending on the time and day)

I have mtr running to the end user's PC (which states around 10% loss at the last node, his router), and about 1% at the first router from the user's PC (so a local Lex I guess).

This has been going on for about 4 weeks, and the ISP keeps saying they're investing the problem with 3rd parties (they don't actually own the raw copper cabling). As internet was fine before that, and is fine during office hours (when people aren't home, or watching digital TV) I'm guessing the issue has nothing to do with the user himself. But rather (an) overloaded router(s).

Is there, besides using mtr and watching the packet loss, a way to find out where the bottle neck is? What router is (most likely) overloaded? And is there a way to see at what router the speed decreases radically?

Kind regards, Tuinslak

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up vote 1 down vote accepted

See oversubscription. Since this concurs exactly to time periods that most are away from their homes, it is very likely the lines are oversubscribed. Besides what you mentioned, there is not much you can do since you need access to the network equipment to see how much traffic is flowing through them at any point in time.

Since they are a reseller they probably don't even have access to this information themselves, which sounds like exactly what they told you.

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All right, thanks. That means I can't do a lot but trying to get them to solve the issue. – Tuinslak Oct 19 '09 at 21:15

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