Patent ID: 8533325

Claim:
A computer-implemented method for identifying an incoming call as being from a mobile device of an enterprise communication system, the method comprising: creating a hashmap comprising: a plurality of keys, each key comprising the last n digits assigned as a Public Land Mobile Network (PLMN) number to at least one mobile device of the enterprise communication system, and a plurality of array elements, each array element: corresponding to a key, and comprising a list of unique identifiers having last n digits of PLMN numbers identical to the key; receiving an Automatic Number Identification (ANI) number of an incoming call to the enterprise communication system; retrieving the array element corresponding to the key comprising the last n digits of the ANI number with the last n digits of the ANI number being a portion of the ANI number; and searching the retrieved array element for the unique identifier associated with the full PLMN number.