Telecommunications system for blocking spoofed calls

A system of a telecommunications network, the system comprising:

• an interconnect session border controller (I-SBC) configured as a network element disposed at a border between the telecommunications network and peer telecommunications networks, the I-SBC including:
• at least one network interface;
• at least one hardware processor;
• and
• at least one non-transitory memory storing instructions, which, when executed by the at least one hardware processor, cause the I-SBC to:
• receive an inbound call over the at least one network interface;
• compare an IP address of the inbound call against a list of allowable IP addresses;
• determine that the inbound call is an illegitimate call,
• wherein an illegitimate call is one which is received by the I-SBC from an IP address that does not match any IP address on the list of allowable IP addresses;
• and
• reject the illegitimate call by not forwarding it to a telecommunications network.

A non-transitory, computer-readable storage medium comprising instructions recorded thereon, wherein the instructions, when executed by at least one data processor of a system, cause the non-transitory, computer-readable storage medium to cause a system of a telecommunications network comprising an interconnect session border controller (I-SBC) having at least one network interface to:

• receive an inbound call over the at least one network interface of the I-SBC,
• wherein a unique call attribute known to a network operator of the telecommunications network is associated with the inbound call;
• cause a Spoofed Call Identification Function (SCIF) to compare the unique call attribute of the inbound call against a list of allowable unique call attributes;
• cause the SCIF to determine that the inbound call's unique call attribute does not match any unique call attribute on the list of allowable unique call attributes,
• wherein when the unique call attribute of the inbound call does not match any unique call attribute on the allowable unique call attribute list, the SCIF identifies the inbound call as an illegitimate call;
• and
• cause the SCIF to reject the call by not forwarding it to a telecommunications network.