Other Protocols

The Protocols page lets system administrators configure settings for all mail server protocols: POP, IMAP, LDAP, and XMPP, as well as related security options such as allowed TLS/SSL versions. These settings determine how SmarterMail processes messages sent and received through each protocol.

• POP
• IMAP
• EWS
• LDAP (Enterprise Only)
• XMPP (Enterprise Only)
• Security Protocols

POP

Use this card to specify the following POP settings:

• POP Banner** - The text that is displayed when initially connecting to the port.
• Command Timeout (Minutes)** - If the server receives a command that sends large amounts of data but the data stops coming in for this number of minutes, the command will be aborted. By default, the command times out after 5 minutes. (Managed on the hub in SmarterMail HA.)
• Max Bad Commands** - After this many unrecognized or improper commands, a connection will be automatically terminated. By default, the maximum number of bad commands is 8.
• Max Connections (0 = Unlimited)** - Some protocols in SmarterMail allow you to specify the maximum number of connections. Increasing this value allows SmarterMail to handle more connections of that type at once, but results in higher CPU and memory utilization. By default, the maximum number of connections is 500.
• Max POP Retrieval Threads - SmarterMail is multithreaded, meaning it can do more than one thing at a time. This setting is for the maximum number of threads you want SmarterMail to work on concurrently for retrieving mail using the POP protocol. By default, the maximum number of POP retrieval threads is 10.
• POP Retrieval Interval (Minutes) - The frequency by which SmarterMail checks for new POP messages. By default, the POP retrieval interval is 1 minute.
• Disable insecure auth methods for non-SSL authentication** - Enabling this will block any insecure authentication types over non-SSL connections.

IMAP

Use this card to specify the following IMAP settings:

• IMAP Banner** - The text that is displayed when initially connecting to the port. The banner supports the use of the following variables, which will be replaced with their corresponding values:
• #HostName#: The hostname grabbed from the URL connected to by the client.
• #ConnectedIP#: The IP address of the client connecting to the mail account.
• #Time#: The current time in the server's timezone. (E.g., Thu, 06 Jan 2022 10:07:54 -07:00)
• #UnixTime#: The current server time translated to a Unix timestamp. (E.g., 1641488874)
• #TimeUTC#: The current server time translated to UTC. (E.g., Thu 06 Jan 2022 17:07:54 +0000)
• Command Timeout (Minutes)** - If the server receives a command that sends large amounts of data but the data stops coming in for this number of minutes, the command will be aborted. By default, the command times out after 15 minutes.
• Max Bad Commands** - After this many unrecognized or improper commands, a connection will be automatically terminated. By default, the maximum number of bad commands is 8.
• < style="color:orangered;">Max Connections (0 = Unlimited)** - Some protocols in SmarterMail allow you to specify the maximum number of connections. Increasing this value allows SmarterMail to handle more connections of that type at once, but results in higher CPU and memory utilization. By default, the maximum number of connections is 1000.
• Max IMAP Retrieval Threads - The maximum number of threads you want SmarterMail to work on concurrently. By default, the maximum number of POP retrieval threads is 10.
• IMAP Retrieval Interval (Minutes) - The frequency by which SmarterMail checks for new IMAP messages. By default, the IMAP retrieval interval is 10 minutes.
• < style="color:orangered;">Enable IDLE Command** - IMAP idle is an extension of the IMAP protocol that allows a mail server to send status updates in real time. Through IMAP IDLE, users can maintain a connection with the mail server via any mail client that supports IMAP IDLE, allowing them to be instantly aware of any changes or updates. When enabled, SmarterMail will inform any connecting IMAP client that it accepts the IDLE command.
Note: IMAP clients that do not fully support IMAP IDLE, like Microsoft Outlook, may use the command in such a way that it actually hinders performance.
• Disable insecure auth methods for non-SSL authentication** - Enabling this will block any insecure authentication types over non-SSL connections.

EWS

Use this card to specify the following EWS settings:

• Max EWS Retrieval Threads - The total number of threads used to process EWS requests.
• EWS Retrieval Interval (Minutes) - How often EWS requests are processed by SmarterMail.

LDAP (Enterprise Only)

Use this card to specify the following LDAP settings:

• Session Timeout (Seconds)** - After a connection fails to respond or issue new commands for this number of seconds, the connection will be closed. By default, the session times out after 300 seconds.
• Command Timeout (Seconds)** - If the server receives a command that sends large amounts of data and the data stops coming in for this number of seconds, the command will be aborted. By default, the command times out after 120 seconds.

XMPP (Enterprise Only)

Use this card to specify the following XMPP settings:

• Max Connections (0 = Unlimited)** - Some protocols in SmarterMail allow you to specify the maximum number of connections. Increasing this value allows SmarterMail to handle more connections of that type at once, but results in higher CPU and memory utilization. By default, the maximum number of connections is 1000.

Security Protocols

SSL and TLS are security protocols that encrypt the transmission of data, allowing users to access their email without the fear that someone has intercepted their data during transit. Use this card to modify the security protocols that are allowed to connect to your mail server.

• System Defaults** - Use System Defaults to allow the operating system to choose the best protocol to use, and to block protocols that are not secure.
• SSL 3.0** - Enable this setting to allow inbound and outbound connections to your mail server over SSL 3.0.
Note: Allowing connections over SSL 3.0 is not recommended. This protocol has been deprecated by the IETF and is considered to be highly insecure.
• TLS 1.0** - Enable this setting to allow inbound and outbound connections to your mail server over TLS 1.0.
Note: Allowing connections over TLS 1.0 is not recommended. This protocol has been deprecated by the IETF and is considered to be highly insecure.
• TLS 1.1** - Enable this setting to allow inbound and outbound connections to your mail server over TLS 1.1.
• TLS 1.2** - Enable this setting to allow inbound and outbound connections to your mail server over TLS 1.2. It is recommended that TLS 1.2, at the very least, is enabled.
• TLS 1.3** - Enable this setting to allow inbound and outbound connections to your mail server over TLS 1.3. Allowing connections via TLS 1.3 ONLY is strongly encouraged.