A: Both vShield Edge and vShield App are part of the VMware vShield suite, and both provide network security services that are similar to network firewalls, but each plays a very different role.
vShield App serves as a firewall within each virtual NIC. That firewall monitors traffic and provides firewall services for each VM by way of their associated virtual NIC(s). This is similar in function to the host-based firewall available in the Microsoft Windows platform; however, vShield App is different in that policies are created and deployed outside the OS.
vShield Edge provides network gateway and security services for edge networks. These edge networks can be DMZs, VPN extranets, or perimeter security for Public Cloud (and, by extension, Hybrid Cloud) computing architectures.