I have a Cable 5mb down connection, typically routed.
For the past few weeks I have been getting considerable lag during what's considered "peek times" by my cable company. It gets to the point where connection is completely lagged where I cannot even send or receive any packets.
I tried a direct connection to one of the PC's and same problem, which pretty much eliminates the router or network load to be the problem.
I tried resetting my modem, checked all the connections, had the line going from the pole outside to the house replaced. It is a dedicated line to the modem so I don't have any splitters to go bad.
Nothing helped. Lag completely prevents me from doing anything online, then it goes away after a few minutes. (please note that the modem does not loose connection).
Cable company claims their end is fine, I have tested everything on my end and the problem persists.
Could it be a bad moded, but if it is, why does it only happen between the hours of 6-10pm?
I had similar problems and it turned out that my ISP had too many people on the same UBR (universal broadband router). There is an upper limit to how many people a single box can support and when you get close to that limit you see lots of lag. I was moved to a different UBR and all was fine.