Network Solution for Windows – Windows system, Linux system, Ubuntu server configuration tip

If you enable the IMAP service, you can specify the port number that the server is to use for IMAP connections. The default is 143.
Likewise, if you enable the POP service, you can specify the port number that the server is to use for POP connections. The default is 110.

You might need to specify a port number other than the default if you have, for example, two or more IMAP server instances on a single host machine, or if you are using the same host machine as both an IMAP server and a Messaging Multiplexor server. (See the document Netscape Messaging Multiplexor for information about the Multiplexor.)

Keep the following in mind when you specify a port:

1. Port numbers can be any number from 1 to 65.535.
2. Make sure the port you choose isn’t already in use or reserved for another service.

Port for IMAP over SSL:

• Messaging Server supports encrypted communications with IMAP and POP clients by using the Secure Sockets Layer (SSL) protocol. See Configuring SSL Encryption and Authentication for general information on support for SSL in Messaging Server.
• You can accept the default IMAP over SSL port number (993) or you can specify a separate port for IMAP over SSL.Messaging Server provides the option of using separate ports for IMAP and IMAP over SSL because most current IMAP clients require separate ports for them. Same-port communication with both IMAP and IMAP over SSL is an emerging standard; as long as your Messaging Server has an installed SSL certificate (see Obtaining Certificates), it can support same-port IMAP over SSL.

Note: Messaging Server 4.0 supports POP over SSL, but not through a separate port from POP. In any case, some client software (such as the current release of Netscape Messenger, the Netscape mail client) does not support POP over SSL.

Service Banner:

• When a client first connects to the Messaging Server IMAP or POP port, the server sends an identifying text string to the client. This service banner (not normally displayed to the client’s user) identifies the server as Netscape Messaging Server, gives the server’s version number, and notes the time of connection. The banner is most typically used for client debugging or problem-isolation purposes.
• You can replace the default banner for the IMAP or POP service if you want a different message sent to connecting clients.