Security is always a headache for enterprises when moving their data and applications to the cloud. Also, with the rapid increase in cyber-threats, security concerns are rising to a peak.

In view of 66% of IT specialists, security is their prevalent concern when it emanates to employ cloud computing infrastructure.

The inevitability of cloud computing proves to be a windfall for companies increasing their workforce agility and productivity but at the same time encouragement of BYOD, access to employee’s cloud via unsanctioned means, or prevalence of shadow IT, the capability to monitor and control the cloud applications such as G Suite, or Office 365 has now become indispensable to the goal of enterprise security.

To rub out the gray cloud, Cloud Access Security Broker emerges as a rescuer addressing existing and surfacing security issues, enforcing security policies in compliance with regulations, even when cloud services are beyond their direct control.

What is Cloud Access Security Broker (CASB)


First devised by Gartner in 2011, CASB is the cutting-edge technology defined as:

A software that “sits between you” – cloud user and vendor, providing visibility and addressing security gaps in the enterprise’s use of cloud services.

Although enterprises whole-heartedly adopting CASB integrating with cloud security, it is essential to know the insight of this emerging technology to better experience its features.

Components of a CASB


  • API

A systematic API is used in CASB to observe activity, scrutinize data, and take immediate measures to rectify if necessary.

  • Gateway

A CASB gateway is integrated amid the operators and the cloud applications to deliver prompt insights and policies of the cloud network.

  • Log Data

CASB ingresses log data from the existing infrastructure such as firewalls, secure web gateways, and SIEMs to guard and examine the flow of data.

  • Agents

Agents in CASB assists in dealing with the cloud activities of employers working on BYOD policy.

Different deployment modes of a CASB

The different technologies used to build CASB architecture gives a variety of deployment options to enterprises to encompass all cloud-related issues. As more people are now relying on CASB for security, Gartner recommends businesses to consider multi-mode CASB that ensures enterprises can expand cloud security as their needs evolve.

CASBs operate in one of the following different deployment modes,

  • Proxy-based CASBs
  • Reverse proxy
  • Forward proxy
  • API-based CASBs

Proxy-based CASBs

This “inline” deployment model uses traditional network technology, by just duplicating the action done by a firewall or gateway. The proxy placed between traffic and cloud application although ensures that data always goes in the protected form to the cloud but also leads to significant network delays and only indemnify identified users.

     Reverse Proxy

In this mode, proxy resides in-front of the cloud service. This agent-less connectivity runs from the internet to the client’s application server, shrouding data that is approaching from the source.

  • Works better for Unmanaged devices

     Forward Proxy

Entailing to be deployed with agents or VPN clients, forward proxy rests in front of the user. The connectivity runs from the client’s network (i.e. firewall) to the internet with CASB proxying data traffic to multiple cloud platforms.

  • Works best for Managed devices


API-based CASBs


API-based CASBs employ the cloud applications’ innate APIs adding a new security layer to already existing stack, allowing direct integration of CASB and cloud service to secure access and activity within the cloud. Since it functions asynchronously so there is no latency in performance.

  • Secure both Managed and Unmanaged traffic

How does a CASB work?


The main idea behind the functioning of the cloud access security broker is to provide visibility and control over stored data, applications and cyber threats in the cloud.

CASB work through a three-step process:

1.    Discovery

By employing auto-discovery, CASB formulates a list of all unauthorized access to cloud services, plus who is using them.

2.    Classification 

Next CASB classifies by determining the risk level associated with residing sensitive data and running applications on cloud platforms.

3.    Remediation:

Now, by using the classified data CASB devise policy for enterprise’s data and user access to meet security requirements and automatically take immediate action when any violation ensues.

Why Business Should Use CASB


CASB is presently an essential bit of any enterprise’s cybersecurity framework. Over time, CASB proved to successfully resolve immense security issues that enterprises encounter while storing data on cloud platforms.

By using Cloud Access Security Brokers, enterprises can:

  • Detect operating Shadow IT within their systems and their risky consequences
  • Identify intruders and impending misuse of cloud services from within or outside the network
  • Better evaluate and adopt cloud services that meet security and compliant mark
  • Enforce multiple layers of advanced security on existing cloud security stack
  • Protect mission-critical data by taking preventive measures like encryption or tokenization
  • Gain visibility into the cloud system
  • Monitor applications and take immediate measures for countering any threat
  • Benefitted by DLP (Data Loss Prevention), Adaptive Access Control (AAC) and User and Entity Behavior Analytics (UEBA) by integrating APIs (Application Program Interface)

Various Security Policies of CASBs


CASB offers multiple advanced types of security policy enforcement that includes:

  • Authentication Access
  • Single Sign-on
  • IP Restriction
  • Device Restriction
  • Device Profiling
  • Geographical Restriction
  • Time Zone Restriction
  • Data Loss Prevention
  • Encryption
  • Tokenization
  • Early Malware Detection and Prevention
  • SSO and IAM integration
  • Logging
  • Credential Mapping
  • Configuration Auditing

Final Word


The next-generation technology Cloud Access Security Broker (CASB), is now gradually making its way to the business world walking along with cloud computing. To experience the countless benefits of CASB it is advised to choose the experienced vendor and first “test-drive” it to ensure you’ve made the right choice and then expand it on a wider platform.

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