Systems and methods of gateway detection in a telephone network

1. A computer-implemented method for detecting gateways, the method comprising:

obtaining, by a computer, call data of a plurality of prior calls associated with a plurality of automatic number identifications (ANIs);

for each ANI of the plurality of ANIs:

generating, by the computer, a feature vector for the ANI based upon a plurality features extracted from one or more prior calls associated with the ANI of the plurality of prior calls; and

generating, by the computer, a gateway score for the ANI based upon the feature vector for the ANI;

identifying, by the computer, at least one ANI as at least one gateway based upon the gateway score of the at least one ANI and a gateway threshold; and

adjusting, by the computer, the gateway threshold according to a contamination factor and a number of gateways identified by the computer.

2. The method according to claim 1 , wherein the contamination factor indicates a number of expected gateways within the call data of the plurality of calls associated with the plurality of ANIs.

3. The method according to claim 1 , wherein the gateway threshold is based on a relative distance of the gateway score from at least one other gateway score.

4. The method according to claim 1 , further comprising:

receiving, by the computer, inbound call data for an inbound call associated with an inbound ANI;

generating, by the computer, an inbound feature vector for the inbound ANI based upon a plurality inbound features extracted from the inbound call data; and

generating, by the computer, an inbound gateway score for the inbound ANI based upon the inbound feature vector.

5. The method according to claim 4 , further comprising identifying, by the computer, the inbound ANI as the at least one gateway based upon the inbound gateway score of the inbound ANI and the gateway threshold.

6. The method according to claim 4 , further comprising authenticating, by the computer, the inbound call associated with the inbound ANI based upon the gateway score of inbound ANI and the gateway threshold.

7. The method according to claim 1 , further comprising receiving, by the computer, the contamination factor from a client device.

8. The method according to claim 1 , further comprising:

determining, by the computer, the plurality of features from each of the prior calls, wherein the plurality of features include at least one of:

a number of calls from the ANI to one or more callees receiving a comparatively larger number of calls normalized by a calls threshold,

a number of calls from the ANI to each type of callee receiving the comparatively larger number of calls,

a lowest interarrival interval between consecutive calls, and

a network type of the ANI.

9. The method according to claim 1 , wherein the call data for each prior call of the plurality of prior calls is extracted according to a lookback window.

10. The method according to claim 1 , wherein obtaining the call data of the plurality of prior calls comprises, for each ANI:

generating, by the computer, a volume score, a spread score, and a call diversity score;

generating, by the computer, a rules-based gateway score; and

generating, by the computer, a combined gateway score based upon the gateway score generated using the feature vector and the rules-based gateway score.

11. A system comprising:

a memory storage configured to store call data for a plurality of prior calls; and

a computer configured to:

obtain the call data of the plurality of prior calls associated with a plurality of automatic number identifications (ANIs);

for each ANI of the plurality of ANIs:

generate a feature vector for the ANI based upon a plurality features extracted from one or more prior calls associated with the ANI of the plurality of prior calls; and

generate a gateway score for the ANI based upon the feature vector for the ANI;

identify at least one ANI as at least one gateway based upon the gateway score of the at least one ANI and a gateway threshold; and

adjust the gateway threshold according to a contamination factor and a number of gateways identified by the computer.

12. The system according to claim 11 , wherein the contamination factor indicates a number of expected gateways within the call data of the plurality of calls associated with the plurality of ANIs.

13. The system according to claim 11 , wherein the gateway threshold is based on a relative distance of the gateway score from at least one other gateway score.

14. The system according to claim 11 , wherein the computer is further configured to:

receive inbound call data for an inbound call associated with an inbound ANI;

generate an inbound feature vector for the inbound ANI based upon a plurality inbound features extracted from the inbound call data; and

generate an inbound gateway score for the inbound ANI based upon the inbound feature vector.

15. The system according to claim 14 , wherein the computer is further configured to identify the inbound ANI as a second gateway based upon the inbound gateway score of the inbound ANI and the gateway threshold.

16. The system according to claim 14 , wherein the computer is further configured to authenticate the inbound call associated with the inbound ANI based upon the gateway score of inbound ANI and the gateway threshold.

17. The system according to claim 11 , wherein the computer is further configured to receive the contamination factor from a client device.

18. The system according to claim 11 , wherein the computer is further configured to:

determine the plurality of features from each of the prior calls, wherein the plurality of feature include at least one of:

a number of calls from the ANI to one or more callees receiving a comparatively larger number of calls normalized by a calls threshold,

a number of calls from the ANI to each type of callee receiving the comparatively larger number of calls,

a lowest interarrival interval between consecutive calls, and

a network type of the ANI.

19. The system according to claim 11 , wherein the call data for each prior call of the plurality of prior calls is extracted according to a lookback window.

20. The system according to claim 11 , wherein the computer is further configured to, for each ANI:

generate a volume score, a spread score, and a call diversity score;

generate a rules-based gateway score; and

generate a combined gateway score based upon the gateway score generated using the feature vector and the rules-based gateway score.