I work on a SCADA system that basically uses a GPRS network to acquire data from remote sites. The 3rd party telecom company providing GPRS allots dynamic IP addresses to the remote devices. We use a Cisco router at the perimeter for managing incoming traffic from these remote sites. In this scenario where IP addresses change periodically, how do I secure my servers using ACLs ? I basically want to make sure that only the traffic coming from the remote sites is allowed into the LAN network of the control center.
Thanks
Khaled
