ISP madness - solved by Ciso VPN, what the??

Hi,

I am posting this here in the hope that the fundamental understanding of networking in this group would provide a resolution to my issue..and I can use a Cisco VPN to sorta fix it, which might point to the issue.

The issue is this: I have a Sweex MO250 wireless ADSL router modem. I can get it to connect to my service provider but I can only browse sites on the google.com domain. Every other site on the web serves me about 20 lines of HTML and nothing else. Google is fast and works normally, as does google video, groups, etc, DNS works fine.

Now, if I install a Cisco VPN client, I can connect through the MO250 to a VPN server and access other sites successfully, but only if I use the VPN client. The VPN cannot be used long-term so I need to fix the core issue.

Could this be an issue or misconfiguration with the MO250? If so, can you tell me what the issue could be? Or do the symptoms define it as a definite problem with the ISP?

Thanks,

Chandy

Sounds very much like an MTU issue, and packet fragmentation. The VPN is probably working around it because it uses smaller packets, but when you are going to varied sites, you will follow their MTU.

Most newer wireless router fix up the MTU along the way. This is an issue with PPPOE, DSL, blah blah blah. How much do you want to know? Google "PPPOE MTU"

Sounds like the Sweex is junk, and failed to learn the lesson of dozens of routers before it. It may need new firmware, but the sweex website is BEYOND lame.

Failing that, use DRTCP to set the MTU of your wireless to 1352 or 1400 or

1492.

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Or using the Cisco SET MTU tool.

I did find an english manual from the OEM at

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Page 144 (PDF page 150) of the OEM manual.

Looks like there is a setting you can check to "enforce PPPOE MTU" or you can lower the MTU on the router itself. Or on the card of your PC. Doesn't matter, really.

Also try updating the wireless driver for your PC. Do all wireless devices have the same problem/