Hi - I have a new twist on this - I notice that many others are suffering with DSL dropouts. This is a 4-machine Windows wired network using a Westell 327 modem - Verizon is the ISP.

The DSL connection was reliable for over a year, then started dropping out every half hour or so. I have narrowed it down to this: It is still reliable with 3 out of 4 machines (one with Vista, one with Windows XP, one local server with Windows 2003) running on the network. When the 4th machine (another XP) starts, DSL drops out late in the boot process, and thereafter does so at random intervals, around 1/2 hour but sometimes quite often. This is reproducible. The Westell log shows this, which is typical:

FRI MAR 14 08:57:22 2008
Connecting session(0): Auto Registration due to Manual Connect

FRI MAR 14 08:57:13 2008
PPP DISCONNECTED on VPI 0 VCI 35 : PPP commanded down

FRI MAR 14 08:57:13 2008
Disconnecting session(0): Auto Registration due to dsl Restart

Since this is associated with a single machine, it seems that it must be something to do with that machine's network configuration. It is certainly not to do with the network traffic - when it is running it handles FTP uploads while several browsers are running, and the failures occur when anything or nothing is going on. But - a half hour or more FTP upload will usually fail when the culprit machine is powered on (and inactive, no browser running, FTP running on one of the other machines).

This is maddening! Any help would be appreciated.

Please also answer this - is the DSL Restart commanded by the modem only, or can the computer issue the command? If the latter, what configuration methods control it?