The Cisco Application Virtual Switch (AVS) is an alternative to the vSphere Distributed Switch (VDS) we set up earlier.
The AVS is based around the Nexus 1000v switch but customized for ACI.
The benefits of the AVS are that it allows you to create a Virtual Tunnel End Point (VTEP) on the VMWare hosts. This enhances scalability (over the VDS) as we are not bound by a one-hop limit. One of the differences between using the DVS and the AVS is that the DVS uses LLDP for VM discovery whereas the AVS uses OpFlex.