My problem is that the users of my intranet, access a system (site) via internet that does ip control conection. I was MASQUERADING the intranet address through only one Public IP. However by the large number of intranet users accessing the system (site) through unique Public IP, the system(site) blocked our Public IP claiming much conections by the same Public IP.
I get a range of Public IPs to use in this solution. Someone knows how do I to randomly release the Public IPs, then, the IP conection output of intranet users would be different each time that the users access the system (site), using my range of Public IP address.
Via software at linux, using iptables, route rules or other method, would be possible do this ?

Someone could help me ?