You can control whether the Messaging Server supports authentication to the SMTP server using SASL (Simple Authentication and Security Layer). SASL is defined in RFC 2222 and or more information about SASL, SMTP authentication, and security is in Chapter 23, Configuring Security and Access Control.
The maysaslserver, mustsaslserver, nosasl, nosaslserver, switchchannel, and saslswitchchannel channel keywords are used to configure SASL (SMTP AUTH) use during the SMTP protocol by SMTP channels such as TCP/IP channels.
nosasl is the default and means that SASL authentication is not permitted or attempted. It subsumes nosaslserver, which means that SASL authentication is not permitted. Specifying maysaslserver causes the SMTP server to permit clients to attempt to use SASL authentication. Specifying mustsaslserver causes the SMTP server to insist that clients use SASL authentication; the SMTP server does not accept messages unless the remote client successfully authenticates.
Use saslswitchchannel to cause incoming connections to be switched to a specified channel upon a client’s successful use of SASL. It takes a required value, specifying the channel to which to switch.