I have an AT&T 3G Microcell that I am trying to get to work in my corporate network. Right now I have a proxy ARP load balancing device; a Fatpipe warp in my DMZ connected to 2 DSL lines and a T1 and firewalled by CISCO ASA 5510's. For the address that the Microcell is using in my LAN i have all ports inbound and outbound open to the Microcell's specific IP address only. Which excludes the firewalls from causing the trouble. My new theory is that because of the Fatpipe and how it routes packets from 3 different addresses that the Microcell cannot communicate properly with AT&T. I could direct all the ports the microcell uses out of 1 fatpipe interface but that would defeat the purpose of some of the fault tolerance/load balancing I have since the ports it uses are also used by other common applications (ie, 443, 123, etc...).
Anyone else have experience in a similar environment? Working or not?