Since the beginning of the COVID-19 pandemic, the focus on zero-trust network access has been on securing remote access to enterprise resources, in order to prevent unauthorized network access by devices and users outside the network. However, zero-trust network access (ZTNA) has evolved into more than just a defense mechanism against external threats.
ZTNA now mandates the authentication of every device that attempts to access network resources, whether they are inside or outside the network. Instead of simply focusing on securing remote access, ZTNA functions as a verification-first framework enabled by security tools, access policies, and more, making it a viable tool to strengthen internal network security.
At its core, zero trust means zero implicit trust — a node in a zero-trust environment doesn’t automatically trust anything that tries to contact it on the network. It always authenticates the other party in a connection and checks that communication remains authorized. Hackers can compromise nodes inside a network and use them to launch lateral attacks, defining what it means to be inside a network, creating issues in a modern, cloud-enabled, remote access enterprise.
ZTNA’s remote access capability operates as always-on, consistently authenticating devices on a network, providing a consistent user experience regardless of whether users work remotely or in a company office. However, expanding ZTNA to data center networks and company LANs is more challenging, as implicit trust doesn’t extend to any network segment or system, requiring identity authentication and verification for every connection request.
Properly implemented ZTNA must be able to identify users and devices in a network, utilizing proper identity and access management (IAM) for users and systems. Security certificates and requesting hosts are used to verify something on a network, and receiving hosts look to an authoritative system for confirmation that the requesting system has proven its identity.
Once ZTNA establishes a node’s identity, the controller checks if current security policies should allow communication between the devices. The controller might also verify that users log in through the requesting system authorized to communicate with the receiving system. Negative entity behaviors in the network can drive the system to update its policy to quarantine or disable access for devices that aren’t behaving properly.
While ZTNA helps organizations protect their internal networks, it also creates difficulties that complicate how enterprises defend against potential internal threats. Access policy configuration and the need for a change in mindset are among the significant challenges of ZTNA, requiring network professionals to shift their perspectives to adopt the zero-trust framework.
Network professionals can use various systems to implement ZTNA in an enterprise network, including SDP, software-defined WAN, microsegmentation services, or a combination of methods. As long as the method of choice provides a way to fully verify every connection, with respect to the identity of the participants and their permission to communicate at that moment, ZTNA can be a reality within a network.
In conclusion, ZTNA is not just a tool to secure remote access, but a comprehensive framework that is designed to ensure the security and integrity of an organization’s entire network, both internal and external. As organizations continue to navigate the challenges of securing their networks in an increasingly digital and remote work environment, ZTNA provides a promising approach to bolstering network security.