Accelerated networking enables single root I/O virtualization (SR-IOV) to a VM, greatly improving its networking performance. This high-performance path bypasses the host from the datapath, reducing latency, jitter, and CPU utilization, for use with the most demanding network workloads on supported VM types.
Reference:
https://docs.microsoft.com/en-us/azure/virtual-network/create-vm-accelerated-networking-cli