3.1.4.2.1.1 Extended Buffer Format

The client or server can choose not to compress the payload if the payload is small enough that compression would not yield much benefit. The client or server can also choose to not obfuscate the payload if the payload has already been compressed or if the client is connected using RPC layer encryption. These options are specified in the Flags field of the RPC_HEADER_EXT structure in section 2.2.2.1.

The extended buffer is used in the EcDoRpcExt2 method, as specified in section 3.1.4.2, for a variety of different fields. The information in section 3.1.4.2.1.1.1 through section 3.1.4.2.1.1.4 describes how the extended buffer is used for the different parameters in this method.