Analyzing the technical architecture of SS7/Diameter interception tools and designing hardware-enforced signaling firewalls.
Surveillance vendors and state actors lease global title addresses on international SS7 networks. By sending SendRoutingInfoForSM (SRI-SM) queries, they obtain the target's current serving MSC/VLR address and IMSI. Subsequent requests allow them to redirect SMS authentication codes or listen to audio streams. TeleHSM provides an un-bypassable hardware barrier that inspects incoming signaling messages at line rate.
TeleHSM inspects the entire protocol stack—MTP3, SCCP, TCAP, and MAP—filtering out spoofed source addresses and verifying that incoming queries correlate with legitimate roaming events. Unauthorized queries are dropped within 500 microseconds before reaching internal subscriber databases (HLR/HSS).
In 4G networks, Diameter replaced SS7 but retained similar trust model assumptions. TeleHSM enforces GSMA FS.19 guidelines, validating cryptographic message origin authentications and preventing malicious Diameter redirect attacks across international interconnects.