Huge speed dropout with BELL sympatico HSE problem

I'm using a Bell's sympatico HSE aDSL connection in Montreal (QC,CANADA). Since a few weeks I have noticed a huge dropout in speed at certain hours. I use

to test my connection speed. I used to get a result of 2.6 kbps almost every time for the past 6 months. But now I very often receive results between 200kbps to 900kbps. I also use I get the same results.

For example at 6:30 pm today I was at 400kbps and now it's 11pm and I see results between 900kbps and 2kbps. I'm well aware that the connection can dropout a bit a peak hours but I never saw anything that bad (and I do tests very often). Last week I even got below a

56kbauds modem for 3 hours! I rarely get the 2.6kbps I've been used to for so long. (sometimes I do, but only for an hour or two)

My home network consist of a SpeedStream aDSL modem (from BELL), a firewall (hardware, a PC running IPcop 1.3), a router (Linksys BEFSR41) and my PCs. For 2 weeks I didn't use my computers at all, everything was working find then. 2 weeks ago I did some research on the web and noticed the speed problem. At first I suspected my firewall configuration (I have modified the IPcop's original configuration a lot) but then I thought that since I didn't change anything on my entire network it shouldn't be a configuration problem. Anyway I tried to connect to the internet without the firewall, without the router (using a direct connection to the aDSL modem) and I also tried using another computer that wasn't used at all for several months and was working very find before. And was always experiencing the same speed problem. So the problem could only came from my phone line or from sympatico!

Here's the reason why I have posted this message to this newsgroup: I tried to use my IPCOP firewall to snif the network traffic using tcpdump on the RED interface (WAN). I have noticed something very strange: I'm now seeing network traffics I wasn't used to see (when no programs, computers where using the internet): I saw many connections on ports 135 and 445 (microsoft-ds). I used to see mostly DNS server connections and pings. The connections do not pass though the firewall so my computers are secure. I think they are only ports scans. If I connect my win2k directly to my DSL modem I get a lot of port scans (80,135,137-138,445 etc...)alerts from sygate's firewall. All connections came from the same network as my WAN ip (using the netmask 255.255.0.0). My IP is dynamic so it's not a computer that is only targeting me.

I have scanned my computers for viruses and spywares and did't find any.

My question is, could it be possible that wildly active worm (scanning these ports) is currently slowing down sympatico's network ? I didn't call sympatico's tech support yet because I saw that other users using sympatico were having the same problem and were told by the tech support that the network was working very find.

If the problem is not on sympatico's side the only thing I could see is a problem with my phone line (but that wouldn't explain the strange port scans), but no changes were made to it and I also tried to disconnect everything connected to it just in case and it didn't change anything.

Are there anyone also experiencing speed problems using sympatico HSE ? Have you heard of a problem on sympatico's network for the past few weeks?

Thanks in advance

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