As long as the 3GPP luh standards are met and I am an existing AT&T customer, is it possible to use a custom built or third party femtocell to connect with the AT&T backhaul?
No. Registration on AT&T's VOIP service (MicroCell) is dependent, in part, on the serial number of the MicroCell unit along with other proprietary identification methods.
MicroCell Technical Guide by Otto Pylot
"Quick Tips: My Microcell Doesn't Work"
I am not an AT&T employee. For additional help, please send a PM to ATTMobilityCare
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