A technician is configuring a new web application to be highly available. The technician has configured multiple web servers in different availability zones at a public cloud provider. The…

A network firewall controls access and filters traffic based on rules but has no mechanism to track or enforce user-to-server session affinity.

An intrusion prevention system monitors and blocks malicious traffic but does not influence how or where user sessions are routed across servers.

While a global load balancer can distribute traffic, its primary function is to spread load across servers, and without additional sticky-session configuration it does not guarantee the same user is directed to the same server each visit.

A VPN creates a persistent, dedicated tunnel between the user and a specific network endpoint, ensuring that the user's traffic is consistently routed to the same server rather than being redistributed on each new connection, which satisfies the requirement for session-to-server affinity across availability zones.