I understand that opening up my CME to the Internet involves some amount of risk but I feel that being
careful about how this is done would minimize the risks and make the positives outweigh the negatives. That
said, I want to confirm what functionality will be available to the remote phones before I proceed with this
What I want to do is to NAT the IP of my CME system and open the minimal amount of ports to have remote SCCP
phones (and also soft phones) connect to it and use its resources. However since these clients will not
have a VPN established they will only have access to the one public IP of the CME system itself. They will
not have IP access to other SCCP phones that are registered to the CME and to the VM system, all of which
have private IPs that are not open to the public Internet. Furthermore, the CME system that these phones
will connect to has SIP connections to other CME systems within the organization also all using private IPs.
I believe that SCCP sometimes uses direct phone-to-phone IP communciations so my question is: Without a
VPN, how many devices will a remote phone or soft phone be able to communicate with? How can I determin which devices will talk to the remotes and which not?
Thanks in advance,