CASB (Cloud Access Security Broker)

A Cloud Access Security Broker is a security control point, usually deployed inline or via API, between users and cloud services, providing visibility, access control, threat protection, and DLP for SaaS and IaaS usage. As operators adopt cloud-hosted OSS/BSS and 5G workloads, CASBs become part of the wider Zero Trust and exposure-management toolkit.

Categories: Security ControlsThreats and AttacksCloud and Virtualization

CASB 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 CASB in the wider telecom-security picture, review A5/0, ASN, BGP Hijacking, Cipher Downgrade Attack, CLI Spoofing and DNS — 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.