Why does UDP 500 need to be forwarded?

Archived from groups: comp.dcom.vpn (More info?)

Solved, it's a Linksys issue.

I tried the connection from another location, where I'm behind 2 firewalls
that don't have UDP 500 forwarded, and it worked perfectly.


> We're a small shop running a Sonicwall SOHO3 using the latest firmware.
> One license for the global VPN client is installed.
>
> At home I have a Linksys WRT54G, also running the latest firmware. In the
> linksys I have to forward UDP port 500 to the IP of the portable. If I
> don'tn the connection won't work. I don't even get a prompt for
> username/password.
>
> Why is this? I can imagine someone wanting to VPN in from say a hotel
> somewhere. It would be unlikely the hotel would forward UDP port 500 to
> someone's laptop during his/her stay. And even if they wanted to do this,
> what if another person wants to VPN to somewhere else? You can't forward
> port 500 twice, now can you?
>
> someone here who can enlighten me?
>
>
> thanks,
>
> David
>
>