ASN (Autonomous System Number)

A globally unique identifier assigned by IANA to networks controlling collections of IP address prefixes. ASNs are critical for internet routing but are vulnerable to BGP hijacking attacks if not secured with RPKI.

Categories: Security ControlsThreats and AttacksInternet and Routing

ASN in context

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.

Telecom threats range from opportunistic SMS phishing and SIM swap to nation-state grade location tracking. The common thread is that most attacks exploit the inherited trust model of legacy signaling protocols.

To place ASN in the wider telecom-security picture, review BGP Hijacking, Egress, IDS, LAN, 3G 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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