2.1 Transport

[C706] specifies two protocol variants within connection-oriented RPC and connectionless RPC. This specification maintains, as specified in [C706], categorization for the descriptions of the RPC protocol variants.

These extensions update the protocol identifiers that are specified in [C706] Appendix I. [C706] specifies that the protocol identifier can be one of three types:

  1. An octet string derived from an interface UUID combined with a version number.

  2. An octet string derived from OSI object identifiers (OIDs).

  3. Single octet identifiers that are registered by the Open Software Foundation for commonly used protocols.

The extensions specified in this document mandate that the third type MUST be used for all communications.

Unless explicitly stated otherwise, the protocol identifier (used by each protocol sequence as specified in sections 2.1.1 and 2.1.2) is as specified in the table in [C706] Appendix I.

The RPC protocol sequence strings for the RPC transports defined by these extensions are specified in the following table.<1>

 RPC transport

 RPC protocol sequence string

SMB

ncacn_np (see section 2.1.1.2)

TCP/IP (both IPv4 and IPv6)

ncacn_ip_tcp (see section 2.1.1.1)

UDP

ncadg_ip_udp (see section 2.1.2.1)

SPX

ncacn_spx (see section 2.1.1.3)

IPX

ncadg_ipx (see section 2.1.2.2)

NetBIOS over IPX

ncacn_nb_ipx (see section 2.1.1.4)

NetBIOS over TCP

ncacn_nb_tcp (see section 2.1.1.5)

NetBIOS over NetBEUI

ncacn_nb_nb (see section 2.1.1.6)

AppleTalk

ncacn_at_dsp (see section 2.1.1.7)

RPC over HTTP

ncacn_http (see section 2.1.1.8)