Feature Group D. An MF signaling protocol, originally developed to support equal access to long distance services,
capable of carrying one or two ten‐digit telephone numbers.
For Wireless 9‐1‐1 call transmission, FGD connectivity allows for delivery of a 20‐digit ANI stream. The ANI stream
contains both the pANI (ESRK or ESRD) and the caller’s callback number.