E911 (Enhanced 911)

Enhanced 911 is the US emergency-services capability that automatically delivers the caller's location and callback number to the dispatcher answering a 911 call. E911 imposes specific obligations on wireless and VoIP carriers (Phase I and Phase II location accuracy, handling of nomadic VoIP) enforced by the FCC, and is the model for similar services worldwide such as E112 in the EU.

Categories: Radio Access NetworkSignalingIdentity and Subscriber

E911 in context

The radio access network is where mobile devices attach to the operator's infrastructure. Attacks in this layer include IMSI catching, rogue base stations and downgrade attacks; defenses rest on mutual authentication, integrity-protected signaling and Open RAN supply-chain hygiene.

Signaling protocols carry the control-plane messages that set up calls, register subscribers and route SMS. SS7, Diameter, GTP-C and SIP are the four dominant families, and interconnect exposure of any of them is treated by GSMA as top-tier telecom risk.

To place E911 in the wider telecom-security picture, review BTS Impersonation (Fake BTS), Cleartext (Plain Text), OFCS, Rogue Base Station (Fake BTS), SMS Pumping and UMTS — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

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