A Cloud Access Security Broker (CASB) is a security policy enforcement point positioned between cloud service consumers and cloud service providers that provides visibility, compliance, data security, and threat protection as organizations access cloud-based resources and SaaS applications.
Context for Technology Leaders
For CIOs managing expanding SaaS portfolios and cloud adoption, CASBs address the visibility and control gap that emerges when data and applications move outside the traditional network perimeter. Enterprise architects leverage CASBs to enforce security policies across sanctioned and unsanctioned (shadow IT) cloud services, ensuring data protection, regulatory compliance, and threat prevention. CASBs have become essential components of cloud security architectures, particularly for organizations in regulated industries.
Key Principles
- 1Visibility and Discovery: CASBs discover and catalog all cloud services in use (including shadow IT), providing risk assessments and usage analytics that inform cloud governance decisions.
- 2Data Security: CASBs enforce data loss prevention (DLP) policies, encryption, tokenization, and access controls to protect sensitive data across cloud services.
- 3Compliance Enforcement: CASBs help organizations enforce regulatory and internal compliance policies across cloud environments, providing audit trails and compliance reporting.
- 4Threat Protection: Advanced CASBs detect and prevent threats including account compromise, malware distribution, and anomalous user behavior across cloud services.
Strategic Implications for CIOs
CASB adoption is critical for CIOs managing regulatory compliance across cloud environments. The CASB market is converging with SASE and SSE (Security Service Edge) platforms, and CIOs should evaluate CASBs as part of integrated security architectures rather than standalone point solutions. Enterprise architects should design CASB deployment models (API, proxy, or log-based) based on security requirements and user experience considerations. Key vendors include Netskope, Zscaler, Microsoft Defender for Cloud Apps, and Palo Alto.
Common Misconception
A common misconception is that CASBs are only needed for shadow IT discovery. While shadow IT visibility is a key CASB capability, modern CASBs provide comprehensive data protection, compliance enforcement, and threat prevention across all cloud services, including sanctioned enterprise applications.