2.1.1 Protocol Sequences
The MSDTC Connection Manager: OleTx Transports Protocol uses several different RPC protocol sequences; it SHOULD use the "ncacn_ip_tcp" RPC protocol sequence.
Also, the MSDTC Connection Manager: OleTx Transports Protocol MAY use either or both of the "ncacn_nb_nb" and "ncacn_spx" RPC protocol sequences. Very few implementations use these protocols, and so they SHOULD NOT be the only protocols supported by a partner.<3>