Re: VPN/RWW not able to establish connection

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Thanks Joe, I just noticed your answer from some days ago.

I have been able to connect for the past several days, so I guess your "correct solution is one that works" is true. Today, after I read your post, disabled the UDP forwarding and everything still works fine. Obviously it was something else I did. I will try rebooting the router later just in case that changes anything after my routing changes.

I did check Google and saw a reference that there was some handshaking going on that did use UDP port 50, but I can't find it now.

thanks again for your input.

Rick

"Joe" <joe@xxxxxxxxxxxxxx> wrote in message news:%23I1pRHy2JHA.1096@xxxxxxxxxxxxxxxxxxxxxxx
Rick wrote:
Well I just took a shot and enabled UDP port forwarding for port 1723 and now it seems to work for both VPN and RWW.

I didn't realize that either used UDP. Can anyone confirm if this is the correct solution?


The correct solution is one that works... preferably without introducing unnecessary security holes in the system.

No, neither application protocol uses UDP. Either:

a) It's a coincidence, and tomorrow it won't work, for some fairly obscure reason, or

b) You have a broken modem/router. That's certainly not as uncommon as it should be, the application programming/scripting of many routers is extremely poor. Ask Mr Google about your model, in particular whether there is later firmware available.

If reconfiguration of your router requires a reboot (unbelievable, but some do) then it's possible it was the reboot which fixed it and not the altered configuration. Even if it didn't reboot, it's possible that the changing of configuration did it, and not what the configuration actually was. I said 'extremely poor', and I meant it.

RWW requires TCP/IP ports 443 and 4125, PPTP VPN (the default method) uses TCP/IP port 1723 and IP protocol 47 (Generic Routing Encapsulation). Absolutely no UDP whatsoever. Since most routers don't explicitly offer protocol forwarding, some will either forward protocol 47 silently if you forward TCP/1723, some apparently do it if asked for TCP port 47 (completely unrelated, it's an obscure FTP protocol) and many offer 'PPTP passthrough', or something similar. Every router has its own web interface and they're all different, even though they all drive one of two or three systems of IP packet-filtering code.

--
Joe

.

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