1.7 Versioning and Capability Negotiation

This document covers DHCP server versioning issues in the following areas:

  • Supported Transports: DHCPM uses the RPC protocol as a transport, as specified in section 2.1 and uses RPC protocol sequences as specified in [MS-RPCE].

  • Protocol Versions: This protocol has only one interface version, but that interface has been extended by adding additional methods at the end. The use of these methods is specified in section 3.1.

  • Security and Authentication Methods: Authentication and security for the methods specified by this protocol are specified in [MS-RPCE].

    The DHCP server asks for the security principal name corresponding to the authentication service RPC_C_AUTHN_GSS_NEGOTIATE (section 2.1.1). This principal name is then used to register authentication information with the RPC layer.

    Immediately after creating a binding, an RPC client using TCP attempts to negotiate authentication method using GSS_NEGOTIATE and authentication level as PKT_PRIVACY (section 3).

  • Localization: This protocol passes text strings in various methods. Localization considerations for such strings are specified in sections 2.2 and 3.1.4.

  • Capability Negotiation: DHCPM does not support negotiation of the interface version to use. Instead, this protocol uses only the interface version number ([C706], section 6.1.2), specified by the Interface Definition Language (IDL) of the DHCP_CLIENT_FILTER_STATUS_INFO_ARRAY structure in Appendix A: Full IDL, for versioning and capability negotiation.