1.4 Relationship to Other Protocols
The NT LAN Manager (NTLM) Authentication: Network News Transfer Protocol (NNTP) Extension uses the NNTP AUTHINFO GENERIC extension mechanism, as specified in [RFC2980], and is an embedded protocol. Unlike stand-alone application protocols, such as Telnet or the Hypertext Transfer Protocol (HTTP), the packets for this protocol extension are embedded in NNTP commands and server responses.
This extension specifies only the sequence in which an NNTP server and NNTP client exchange NTLM messages in order to successfully authenticate the client to the server. It does not specify how the client obtains NTLM messages from the local NTLM software or how the NNTP server processes NTLM messages.
The NNTP client and NNTP server implementations depend on the availability of an implementation of the NTLM Authentication Protocol, as specified in [MS-NLMP], in order to obtain and process NTLM messages; and depend on the availability of the base64 encoding and decoding mechanisms, as specified in [RFC1521], to encode and decode the NTLM messages that are embedded in NNTP packets.