Well I have never seen a case on Netvigator (or at least not since the days of the very old ATM-based TV service) where the IP address reported by my router was any different from the IP address reported by any of the many websites or other services out there which purport to tell me my IP address. And by all the tests I can run that IP address is solely in use for my connection.
Netvigator may well (indeed I would hope it does) use a caching proxy to minimise use of bandwidth and improve download times, but that is not, per se, going to have the effect that the OP described. This will only happen if s/he has a proxy configured in their browser or if Netvigator uses an intercepting proxy which would give the address translation effect described. In my experience Netvigator does not run such a proxy.
The other possibility is that the OP's machine has been compromised and is, unbeknownst to him/her, running some proxy code itself which is being used for some (probably nefarious) purpose by other people.