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New Member


I have an application that requires a site-to-site VPN tunnel that looks like the same network segment on the inside. Am I looking at a GRE tunnel?


Re: tunnel


It depends on your network setup, it could be a point 2 point GRE tunnel or IPSEC.

But if you setup a GRE tunnel over a Pulic network use IPSEC over it for encrytion.

Re: tunnel

Could you also brief about the application? how it works?

New Member

Re: tunnel

It is a Fonality VOIP server (softswitch) In order to configure the phones initually they need to be on the same segment. I haven't got the exact details but it's probably some kind of bootp type deal. The softwitch is in Chicago. Main office is in New Orleans. I was going to purchase two 851 routers to set up a tunnel between the sites to configure the phones.

Re: tunnel

u need to run site to site vpn in network extention mode

if u need to use routing protocol or multicast over the vpn

then u need to use gre over ipsec

otherwise only ipsec enough

if u need more details, just ask

good luck

rate if helps