Internet Direct (Indy) Version 9.0.2 Beta
TIdRawBase.Protocol
Identifies the protocol option for the socket connection.

property Protocol: Integer;
Description
Protocol is an Integer property that identifies the protocol used for the socket connection. The default value for Protocol is Id_IPPROTO_RAW, as established in Create.

Binding.AllocateSocket uses the Protocol property to bind both the protocol family and protocol options for the socket handle.