A CASB is a cloud access security broker that protects cloud services. Cloud Security Alliance lists four primary services in visibility and data security and threat protection and compliance. Gartner coined the term in 2011. Early CASBs exposed shadow IT while current ones protect SaaS and IaaS data.
Employees sign up for cloud apps without telling IT so sensitive files end up in places nobody tracks. CASB products address that gap.
This guide follows articles from CSA and Microsoft.
What is a CASB?
According to the Cloud Security Alliance a CASB protects cloud services. Gartner coined the term in 2011 when most applications sat in data centers and few companies trusted the cloud. See what is a CASB.
Early CASBs gave visibility into shadow IT and limited employee access to unauthorized cloud services. Current CASBs protect cloud hosted data and apply enterprise security controls to SaaS and IaaS.
What are the Four Pillars of a CASB?
| Pillar | What it Does |
|---|---|
| Visibility | Finds sanctioned and unsanctioned cloud services including shadow IT and rates the risk of every connection |
| Data security | Enforces policies through data classification and access controls and encryption |
| Threat protection | Guards against malware and phishing and account takeover and malicious links |
| Compliance | Provides auditing and reporting and SIEM integration and automated enforcement for rules like GDPR and HIPAA |
How does Microsoft Describe CASB Functions?
Microsoft lists shadow IT discovery and visibility into cloud app usage and protection against app based threats and information protection as fundamental CASB functionality. See Microsoft cloud app security documentation.
Microsoft also describes a discovery flow of three steps. Identify finds apps used on and off the corporate network. Assess rates them against more than 90 risk indicators. Manage sets policies that monitor apps and alert on anomalies.
When does a Business Need a CASB?
- Unknown apps. Teams use cloud apps that IT never approved.
- Sensitive data. Files with regulated data sit in SaaS storage.
- Audit pressure. Rules like GDPR and HIPAA call for reports and enforcement.
For access control see cloud identity and access management. For shared files see shadow IT and cloud data protection controls.
Frequently Asked Questions
What does CASB Mean?
CASB stands for cloud access security broker. This product protects cloud services.
What are the Four Pillars of CASB?
They are visibility and data security and threat protection and compliance.
Who Defined the Term CASB?
CSA credits Gartner with the term in 2011.
What does CASB Visibility Mean?
It means finding sanctioned and unsanctioned cloud services including shadow IT and rating their risk.
Does a CASB Protect IaaS?
Yes. Current CASBs apply enterprise security controls to SaaS and IaaS.
Key Takeaways
- CASB products protect cloud services and the data inside them.
- Visibility and data security and threat protection and compliance form its four pillars.
- Gartner coined the term in 2011.
- Visibility starts with finding shadow IT.
- Current CASBs protect SaaS and IaaS.
Sources and References
This guide follows the Cloud Security Alliance and Microsoft documentation.
- What is a CASB (Cloud Security Alliance) cloudsecurityalliance.org
- Cloud app security overview (Microsoft Learn) learn.microsoft.com