Secure Password Authentication (SPA) is a proprietary
Microsoft
Microsoft Corporation is an American multinational corporation, multinational technology company, technology corporation producing Software, computer software, consumer electronics, personal computers, and related services headquartered at th ...
protocol used to authenticate Microsoft
email
Electronic mail (email or e-mail) is a method of exchanging messages ("mail") between people using electronic devices. Email was thus conceived as the electronic ( digital) version of, or counterpart to, mail, at a time when "mail" mean ...
clients with an electronic mail server when using the
Simple Mail Transfer Protocol
The Simple Mail Transfer Protocol (SMTP) is an Internet standard communication protocol for electronic mail transmission. Mail servers and other message transfer agents use SMTP to send and receive mail messages. User-level email clients typic ...
(SMTP),
Post Office Protocol
In computing, the Post Office Protocol (POP) is an application-layer Internet standard protocol used by e-mail clients to retrieve e-mail from a mail server. POP version 3 (POP3) is the version in common use, and along with IMAP the most comm ...
(POP), or
Internet Message Access Protocol
In computing, the Internet Message Access Protocol (IMAP) is an Internet standard protocol used by email clients to retrieve email messages from a mail server over a TCP/IP connection. IMAP is defined by .
IMAP was designed with the goal ...
(IMAP).
[http://www.kuro5hin.org/?op=displaystory;sid=2002/4/28/1436/66154] The protocol was based on the
Integrated Windows Authentication
Integrated Windows Authentication (IWA)
is a term associated with Microsoft products that refers to the SPNEGO, Kerberos, and NTLMSSP authentication protocols with respect to SSPI functionality introduced with Microsoft Windows 2000 and included ...
(NTLM) authentication scheme.
References
Microsoft Windows security technology
Password authentication
Email authentication
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