Microsoft Azure Solutions Architect Expert AZ-305 Practice Question

Global virtual network peering links the two VNets directly across Microsoft's private backbone, so traffic never leaves Azure, incurs no encryption or tunnelling overhead, and can reach line-rate bandwidth limited only by the virtual machine NICs (up to 50 Gbps per VM). No gateways, route tables, or additional appliances are required, keeping operational complexity low.

Site-to-Site VPN or VNet-to-VNet connections send packets over IPSec tunnels that cross the public internet, adding latency and reducing throughput. A hub-and-spoke design that forces traffic through an Azure Firewall adds extra hops and performance overhead. ExpressRoute Global Reach can connect two circuits, but each VNet would need a dedicated ExpressRoute circuit, greatly increasing cost and management effort for performance similar to peering. Therefore, global VNet peering best meets the performance and simplicity requirements.