As mentioned previously, application programmers use the standard Windows Sockets 2 protocol enumeration method to discover SSL-enabled transports. Invoking WSAEnumProtocols returns a buffer filled with WSAPROTOCOL_INFO structs, with one such struct for each available transport protocol. Transports which have been enhanced with SSL capabilities have this indicated in the iSecurityScheme field of their WSAPROTOCOL_INFO struct. This field will contain the value:
SECURITY_PROTOCOL_SSL