Network protocol support requirements
You must be aware of the network protocol requirements for implementing ONTAP BranchCache.
You can implement the ONTAP BranchCache feature over IPv4 and IPv6 networks using SMB 2.1 or later.
All CIFS servers and branch office machines participating in the BranchCache implementation must have the SMB 2.1 or later protocol enabled. SMB 2.1 has protocol extensions that allow a client to participate in a BranchCache environment. This is the minimum SMB protocol version that offers BranchCache support. SMB 2.1 supports version BranchCache version 1.
If you want to use BranchCache version 2, SMB 3.0 is the minimum supported version. All CIFS servers and branch office machines participating in a BranchCache 2 implementation must have SMB 3.0 or later enabled.
If you have remote offices where some of the clients support only SMB 2.1 and some of the clients support SMB 3.0, you can implement a BranchCache configuration on the CIFS server that provides caching support over both BranchCache 1 and BranchCache 2.
Even though the Microsoft BranchCache feature supports using both the HTTP/HTTPS and SMB protocols as file access protocols, ONTAP BranchCache only supports the use of SMB.