According to VMware, “Micro-segmentation enables organizations to logically divide its data center into distinct security segments down to the individual workload level, and then define security controls and deliver services for each unique segment.” (Lawrence Miller, CISSP and Joshua Soto, 2015, p. 21) The benefit of micro-segmentation is that it denies an attacker the opportunity to pivot laterally within the internal network, even after the perimeter has been breached.
VMware NSX-T supports micro-segmentation as it allows for a centrally controlled, yet distributed firewall to be attached directly to workloads within an organization’s network. The distribution of the firewall for the application of security policy to protect individual workloads is effective as rules can be applied that are specific to the requirements of each workload. The additional value that NSX-T provides is that the capabilities of NSX are not limited to homogenous vSphere environments, but support the heterogeneity of platforms and infrastructure that is more commonly used with many organizations today. Figure 7 depicts micro-segmentation capabilities of NSX, where each workload is virtual secured with its own distributed firewall.
Micro-segmentation provided by NSX-T better supports a Zero Trust architecture for IT security such that it allows for perimeters to be established around each workload. The Zero Trust architecture was introduced by analyst firm Forrester Research as an alternative approach to IT security architecture. Conventional security models assume that everything on the inside of an organization’s network can be trusted, whereas the Zero Trust model assumes the opposite: that nothing can be trusted and everything should be verified. The Zero Trust model for IT security is a principle that addresses the increased sophistication of network attacks and insider threats.
Rather than simply placing firewalls at the edge of the organization’s network to prevent attacks from external networks, the Zero Trust model looks at ways to better control and manage network traffic within the organization’s network. The intent is that for each system in an organization’s network, trust of the underlying network is completely removed. To do this, organizations can define perimeters within the network to limit the possibility of lateral (east-west)movement of an attacker. Implementation of a Zero Trust model of IT security with traditional network security solutions designed primarily to protect the organization’s edge can be costly and complex.
Moreover, the lack of visibility for organization’s internal networks can slow down implementation of a Zero Trust architecture and possibly leave gaps that may only be discovered during a breach. Additionally, internal perimeters may only have granularity down to a VLAN or subnet, as is common with many traditional DMZs. However, network virtualization solutions like NSX and NSX-T can provide a more cost effective and efficient means to implement a Zero Trust network