MNP (Mobile Number Portability)

Mobile Number Portability lets subscribers change operator while keeping their MSISDN, mandated by regulators in most markets. It is implemented through a national number portability database that operators query during call/SMS routing. MNP processes are also a frequent attack surface for SIM-swap-style social engineering, where an attacker ports the victim's number to an operator they control.

Categories: Identity and SubscriberSecurity ControlsThreats and Attacks

MNP in context

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

Security controls span signaling firewalls (SS7/Diameter/GTP screening), transport encryption (IPsec, TLS, PRINS), identity and access on OSS/BSS, and monitoring at both packet and log level. Controls are audited against GSMA FS.11/FS.19/FS.20/FS.36.

To place MNP in the wider telecom-security picture, review Event Logging, SIM, SNMP, 2G, AAA and A5/0 — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

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Browse the full TelcoSec Glossary, the Ultimate Guide to Mobile Network Security, or the P1 Arsenal of telecom-security tools.