GNO Mail Connection Information

Purpose

This document is intended for GNO mail system users. It is provided as a description of services so as to give users sufficient information so that they can configure standalone mail clients for use with this system.

The Information in Brief

Here, in brief, is the information you need in order to connect to our mail server:

    MDA:
        hostname:               mail.gno.org
        protocols:              IMAPS, POP3S
                                (avoid POP3S if you also want to use webmail)
        security:               SSLv3
        authentication method:  plain

    MTA (optional):
        hostname:               smtp.gno.org
        protocols:              SMTP
        security:               TLSv1 or TLSv3
        authentication method:  plain

Do note that the authentication method is plaintext over SSL. If you select options in your client like "CRAM/MD5" or "secure password" then you will not be able to properly authenticate.

Terminology

Almost all modern mail systems have three main components. They are:

1. The MUA or Mail User Agent. This is your mail reader, such as Netscape Communicator, Eudora, Pine, or Mulberry.
2. The MDA or Mail Delivery Agent. This is the server to which you connect to retrieve your mail. Two types commonly-known MDA protocols are POP and IMAP.
3. The MTA or Mail Transport Agent. This is the server to which you connect in order to send new mail. The most common MTA software is sendmail, but there are other types. Most MTAs use the SMTP protocol.

General Information

This server provides access to two MDA protocols, which we summarize here:

1. IMAP over SSL With IMAP, your mail is always kept on the server (until you delete it and expunge the deleted messages from your mailbox, or move your mail to another mailbox). Your client may keep a cached copy of your mail so as to minimize network traffic. If your client supports disconnected-mode IMAP, then you can read your mail while disconnected from the server (which is a good idea for dialup accounts). IMAP accounts support multiple sub-mailboxes under your primary mailbox, thus making sorting of mail easier.
2. POP3 over SSL POP clients usually have two modes, "download and keep mail on server", and "download and delete mail from server". The former is similar to IMAP, but without the benefit of multiple mailboxes on a given server, and thus no sorting. With the latter, the server has no record of your mail after it is downloaded. This can be good if you're worried about exceeding your mail quota, but bad if your client crashes and loses all of your email.

Note that the download-and-delete mode of POP clients is not compatible with using the webmail interface. If you want to use both your stand-alone email client and the webmail system, then stick to IMAP with the former.

Since we don't provide technical support for your mail client, you're of course welcome to use whatever mail client you want. A generally good client that runs on MacOS, Windows, and a few UNIX variants including Linux and Solaris is Mulberry. Mulberry used to be a commercial product, but is now freely available.

The MTA, in the interests of spam (UCE/UBE) control, has restrictions on the type of mail it will handle. Inbound mail will, in general, be allowed only if it is addressed to gno.org or other domains hosted by this site. Various other types of anti-spam measures are also in place in order to cut down on the crud being delivered to our users. It's not perfect, but it gets rid of most of the junk mail.

In the interest of supporting mobile computing, the MTA will accept arbitrary mail from clients which have logged in. The supported authentication method is plaintext username/password over TLSv1 or TLSv3 (which are like SSL except that encryption is negotiated after the SMTP connection has been initiated).