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TCP Stops Working

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by dragon emperor 2 views

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Since I switched ISPs the computers on my LAN have had their TCP stop working when the internet is connected (usually after 10-15 minutes, but on occassion it hasn't happened till much later). At that time no packets even seem to be going out. Applications using UDP (such and my internet phone) continue functioning without problems. The ISP has been unhelpful in solving the problem (I believe it happens after the lights on the wireless modem flicker, which they claim should never happen but does). Once it happens I have to reboot. Is there a simpler way to handle or even prevent this problem?

12 replies

by chris910

Check For Viruses on your computers Possibly one of the blaster variants and then make sure that the RPC Patch and the patch for Sasser is installed

by dragon emperor

I have Panda Antivirus Platinum 7 on my systems (and I keep it up to date), plus I keep my systems patched. Additionally I have Sygate Personal Firewall PRO.

by net designer

Install Ethereal on one of computers and scan for excessive ICMP packets. If it happens, note the source and scan for viruses as was suggested previously.

by dragon emperor

My Antivirus program and Firewall are very good at catching attacks (which seem to have increased with the new ISP).

by sgt_shultz

did you switch routers when you switched isp's? what elso changed? make sure you have as good quality phone lines to the dsl router as possible. try to filter right after the router (aka 'wireless modem'). keep the unfiltered distance as short and direct as possible, see? then try another router. not all will support the dsl protocol your telco\isp use so check with isp first or plan on returning router possibly...

by dragon emperor

No, my router changed the same. A SMC Barricade 7004BR, and I have tried direct connection as well with the same results. It is wireless broadband, not DSL. The only change at that time was the change in ISP.

by dragon emperor

I should also note that the quality of this connection appears better than with my previous ISP, which had major latency and bandwidth problems (hence returning to it is not an option).

by chris910

When you say that your TCP stops working might you mean that DNS resolution stops working? Try accessing your internal network using IP addressing. (ie \\192.168.1.2\Cdrive instead of \\station1\Cdrive) If my suspicions are correct you may be having DNS issues not TCP Problems.

If the above is not the Issue: Try some of the tools located at http://www.dslreports.com/tools. Yes I know You dont have DSL but most of the tools work for Broadband as well :-)

by dragon emperor

No, I mean that services that use TCP no longer show any packet communication. My email and browser fail to work. Ping, my LAN, my internet phone, and games continue to work fine. Since browsing does not work I cannot use dslreports once the problem starts. When the problem is not in effect my connection speed and quality show to be rather good by the tools at dslreports.com (I have long been a member there).

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