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 in telecom span signaling firewalls (SS7/Diameter/GTP screening at the network edge), transport encryption (IPsec, TLS, PRINS), identity and access on OSS/BSS, and monitoring at both the packet and log level. Controls are audited against GSMA FS.11/FS.19/FS.20/FS.36 and, in Europe, NIS2 sectoral rules.

Telecom threats range from opportunistic SMS phishing and SIM swap to nation-state grade location tracking and lawful-interception abuse. The common thread is that most attacks exploit the inherited trust model of legacy signaling. SS7 and Diameter were designed for a closed operator community that no longer exists.

To place ASN in the wider telecom-security picture, review BGP Hijacking, BGP, Egress, A5/0, CVE and IDS.

Related terms

Related topic hubs

  • Diameter Attacks S6a IDR/PUR/CLR abuse, subscriber tracking, LTE signaling attacks.

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