PEI (Permanent Equipment Identifier)

In telecommunications, the PEI is the 5G equivalent of the IMEI, identifying the mobile equipment itself rather than the subscriber. It is checked by the network (potentially against an EIR) to detect stolen or non-compliant devices.

Categories: Identity and SubscriberInternet and RoutingIoT

PEI in context

Subscriber identifiers (IMSI, SUPI, MSISDN, IMEI) are the anchor for authentication, charging, lawful interception and fraud analytics. Any protocol or interface that leaks a permanent identifier is treated as a serious privacy defect, which is why 5G introduced SUCI concealment on the air interface.

Telecom networks depend on Internet-style routing (BGP, DNS, MPLS) for interconnect, transport and application delivery. Route hijacks and DNS abuse can degrade or intercept signaling as easily as any application-layer attack, which is why RPKI and DNSSEC are now standard hardening for carrier networks.

To place PEI in the wider telecom-security picture, review Demarcation Point (Demarc), Endpoint, IMEI, TAC, SIM Box and IP Address.

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