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- Network security manager MUST be available & enabled to initialize the server insecure mode.
- If anything goes wrong while trying to connect to the server, the socket isclosed by calling NetSock_Close. Hence, all data structures are returned to their original state in case of a failure to establish the TCP connection. If the failure occurs when initiating the session, the application is responsible of the appropriate action(s) to be taken.
- If authentication is disabled (SMTPc_CFG_AUTH_EN set to DEF_ENABLED), the 'p_username' and 'p_pwd' parameters should be passed a NULL pointer.
- The server will send a 220 "Service ready" reply when the connection is completed. The SMTP protocol allows a server to formally reject a transaction while still allowing the initial connection by responding with a 554 "Transaction failed" reply.
- The Plain-text (PLAIN) authentication mechanism is implemented here. However, it takes some liberties from RFC #4964, section 4 'The AUTH Command', stating the "A server implementation MUST implement a configuration in which it does not permit any plaintext password
mechanisms, unless either the STARTTLS command has been negotiated or some other mechanism that protects the session from password snooping has been provided". Since this client does not support SSL or TLS, or any other protection against password snooping, it relies on the server NOT to fully follow RFC #4954 in order to be successful. - To resolve the SMTP server adress with it name domain, be sure that µC/DNSc has been correctly initialized.
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