Change ISP - Static IP issues

[grot1001]

For many years I've been with the same ISP on a static IP address.
I've setup many clients with RealVNC for remote control support and have restricted their firewall/routers to forward VNC ports in conjunction with my static IP address only.
You know whats the question is now I guess. ;)

When/if I change ISP then I will lose my static IP address! :(

Is there a way to spoof my old IP address easily or do I have to re-visit all my clients?

Furthermore, can anyone suggest a setup that will give similar security to my clients but free me from using a static IP?

Any advise much appreciated.

G

[awaj]

I don't know the answer to your first question, but Log me in may do what you want it to do.

[Paul Komski]

There's no way that I know about to spoof a public IP address from another domain; it's what is publicly broadcast from your internet connection and once released would only to be found by any DNS servers within the original domain and would probably be re-allocated in any case.

Furthermore, can anyone suggest a setup that will give similar security to my clients but free me from using a static IP?

What you could have done and could do for the future is to use something like dyndns (http://www.google.ie/url?sa=t&source=web&ct=res&cd=1&url=https%3A%2F%2Fwww.dyndns.com%2F&ei=aQuFSqiuIOXPjAfJvpyiCw&rct=j&q=dyndns&usg=AFQjCNEWc1czf8ED1dhikX2H3yGJF4lGUA) such that you give out and use the domain name you register with them but it gets constantly updated with your current IP address from the software running on your PC or directly from your router (if it contains that facility).

[grot1001]

Thanks guys, I already use dyndns for my clients since my control initial contact is the other way around.

But you reminded me that RealVNC has a feature I never used. Called something like remote listening viewer.
I think that should allow me to have a dnydns name and let customers request support remotely. If I can get it to work that should also save previous firewall navigation issues. :)

Thanks for the replies.

[Variable]

No, can't spoof an IP and actually communicate. You need to change the ACL in each of the router/firewalls. If the router/firewall allow you to create a traffic rule and use a dns name... you could control dns with a domain you own. It may be possible but I have always used an IP. Maybe an ASA might do a lookup first.

In any case, I would access the router prior to the change and add an exception for the new ISP with something like a class A mask. They may tell you your new IP will be one thing and then it changes when it actually is set up. I have seen that happen. If you have already made your router changes... your screwed. You may be able to give yourself a little wiggle room by opening up the rule with a 255.0.0.0 temporarily and then fixing it when your done.

I would use RDP instead of VNC. It is much better all around from an admin standpoint - if you use windows machines..