Mail/MMDF glossary

alias -- A name that MMDF translates into a corresponding mail address or a list of mail addresses. Using an alias, you can specify a single name to represent a group of mail users. For example, using an alias called sales that includes mike, tom, sally, and sue (members of the sales department), you can address mail to ``sales'' and mike, tom, sally, and sue will each get a copy.

alias loop -- A state that occurs when an alias includes a member alias of which the original alias is a member (for example, alias B is a member of alias A, and alias A is a member of alias B).

attachment -- A special mail item that is associated with a multipart mail message. One or more attachments may be included in a single mail message. An attachment may contain ASCII text, data from a spreadsheet or a word processor, a graphical image, or audio or video information.

badhost -- A mail channel through which all mail addressed to unrecognized hosts is routed. The mail is then directed to the smart host.

baduser -- A mail channel through which all mail addressed to unrecognized users is routed. The mail is then directed to the smart host.

bounced mail -- Mail that is returned to the sender as undeliverable.

channel -- A method that permits a machine to exchange data using a single type of network communications protocol. It handles the mail transport protocol so that neither the operating system nor the rest of the MMDF system has to know about the intricacies of a particular mail transport protocol. Channels act not only as protocol handlers, but in some cases actually initiate the communications to the network or to another machine as needed. They also may convert address or message formats as necessary.

channel input program -- The program used by a channel to monitor and manage incoming mail. For example, /usr/bin/rmail is used by the UUCP channel.

channel output program -- The program used by a channel to process outgoing mail. For example, /usr/mmdf/chans/uucp is used by the UUCP channel.

channel queue -- The holding space used by a channel for incoming or outgoing mail that is waiting to be delivered.

domain name -- A name used for mail delivery that describes the site where a computer is located and generally includes the machine (host) name, a department (optionally), and the site's organization or country.

domain name server -- A computer that maintains a database that can provide information about host names and addresses within a domain. See name server.

domain tables -- Tables that are used to match a short host name to its fully qualified host name. Domain tables can be used to convey information to MMDF about how machines are connected and about any special domain routing considerations.

fully qualified domain name -- The full name of a host, by which it can be uniquely identified. The name includes the machine name and the full name for the domain to which it belongs. Also called the fully qualified host name.

fully qualified host name -- Same as a fully qualified domain name.

hashed database -- MMDF configuration information built by dbmbuild(ADM) and maintained for quick verification of addresses and efficiency in assigning channels to submitted messages. The hashed database must be rebuilt after manual modification of MMDF configuration files.

headers -- Information included at the top of every MMDF mail message. Headers minimally identify the message sender, recipient, and the date it was sent, and can optionally provide other information such as carbon copy recipients, message ID information, and message priority.

host -- Any computer that supports exchange of mail over MMDF. See local host.

Host name -- Sometimes called a system name or machine name. The name of the machine on which you are configuring MMDF. To determine the local host name, enter uname -n at the UNIX system prompt. An example of a host name is scribe.

MMDF allows host names to contain underscore characters; this is an extension of internet standards. To ensure interoperability with hosts that strictly conform to internet standards, we recommend that you do not use the underscore character when internetworking is a primary goal.

local host -- The machine on which you are currently managing MMDF.

mailing list -- A special type of alias. Each mailing list has an ``owner'' who handles list administration and receives any error messages about bounced messages or other problems with list mail. Mailing list addresses are not validated at the time each message is sent, which can save a significant amount of processing time with a large list of recipients.

Mail Transfer Agent (MTA) -- A facility that accepts messages generated by an Mail User Agent, determines a route for delivery, edits the message header as required by the destination and delivery program, and calls the appropriate delivery program to deliver the mail. SCO OpenServer systems provide two MTAs: MMDF and sendmail(ADMN).

Mail User Agent (MUA) -- A program that provides a user interface for mail message processing, including mail composition and reading. SCO OpenServer systems provide three MUAs: mail(C), scomail(XC), and SCO Shell Mail.

MIME -- Multipurpose Internet Mail Extensions. A standard for mail exchange that supports graphical, audio, video, and multimedia messages. MMDF is MIME compliant.

MMDF -- Multichannel Memorandum Distribution Facility. One of the two Mail Transfer Agents used on SCO OpenServer systems. The other is sendmail. MMDF provides transparent access to the different networks and mail transport protocols, regardless of the Mail User Agent employed (one or more MUAs may be used on a single system).

MMDF Alias Administration Manager -- A program that provides an interactive interface for accomplishing daily administration of your mail aliases.

Start the Alias Administration Manager by selecting Toolsheds from the Desktop Tools menu, double-clicking on the System_Administration Tools icon, double-clicking on the Mail icon, and double-clicking on the MMDF Alias Admin icon.

MMDF Channel Administration manager -- A program that provides an interactive interface for accomplishing advanced administration of your mail channels.

Start the Channel Administration Manager by selecting Toolsheds from the Desktop Tools menu, double-clicking on the System_Administration Tools icon, double-clicking on the Mail icon, double-clicking on the MMDF_Advanced_Admin icon, and double-clicking on the MMDF Channel Admin icon.

MMDF Configuration manager -- A program used for configuring MMDF on the local host. This program may be run at installation time and any time after that when the system undergoes a major change, such as when you connect your machine to a new network or remove it from an existing one.

Start the MMDF Configuration Manager by selecting Toolsheds from the Desktop Tools menu, double-clicking on the System_Administration Tools icon, double-clicking on the Mail icon, and double-clicking on the MMDF Configuration icon. Alternatively, enter mkdev mmdf at a command line.

MMDF Domain Administration manager -- A program that provides an interactive interface for accomplishing advanced administration of your mail domains.

Start the Domain Administration Manager by selecting Toolsheds from the Desktop Tools menu, double-clicking on the System_Administration Tools icon, double-clicking on the Mail icon, double-clicking on the MMDF_Advanced_Admin icon, and double-clicking on the MMDF Domain Admin icon.

MMDF Host Administration manager -- A program that provides an interactive interface for accomplishing daily administration of your mail hosts.

Start the Host Administration Manager by selecting Toolsheds from the Desktop Tools menu, double-clicking on the System_Administration Tools icon, double-clicking on the Mail icon, and double-clicking on the MMDF Host Admin icon.

MMDF Table Administration manager -- A program that provides an interactive interface for accomplishing advanced administration of your mail tables.

Start the Table Administration Manager by selecting Toolsheds from the Desktop Tools menu, double-clicking on the System_Administration Tools icon, double-clicking on the Mail icon, double-clicking on the MMDF_Advanced_Admin icon, and double-clicking on the MMDF Table Admin icon.

name server -- A program running on a network that provides a central database of information, such as Internet addresses and the names of hosts on which people receive mail.

postmaster -- An address that is required for every domain on the Internet by RFC 821/822. People send inquiries about user and host names to the postmaster address in that domain.

RFC 822 -- Internet Technical Bulletin, available from the InterNIC Registration Services, or InterNIC. See ``Registering domain names'' for more information.

smart host -- A computer that has more complete information about the entire mail network than do local hosts. Mail addressed to hosts or users unknown to a local host can be forwarded to the smart host over the badhosts or badusers channels.

SMTP -- Simple Mail Transfer Protocol. The mail transfer protocol used over TCP/IP and the Internet.

smtp -- An MMDF channel used to exchange messages over TCP/IP using the Simple Mail Transfer Protocol.

subdomain -- A registered name that describes a company, department, or any subgroup under a top-level domain name. company_name is an example of a subdomain in the domain COM.