access control.  A method for controlling access to a server or to folders and files on a server.

access domain.  Limits access to certain Messaging Server operations from within a specified domain. For example, an access domain can be used to limit where mail for an account can be collected.

account.  Information that defines a specific user or user group. This information includes the user or group name, valid email address or addresses, and how and where email is delivered.

action.  A component of a UBE filter; it specifies the action that is to be performed if a match occurs.

address.  Information in an email message that determines where and how the message must be sent. Addresses are found both on message headers and on message envelopes.

address handling.  The actions performed by the MTA to detect errors in addressing, to rewrite addresses if necessary, and to match addresses to recipients.

addressing protocol.  The addressing rules that make email possible. SMTP is the most widely used protocol on the Internet and the protocol supported by the Netscape Messaging Server. Other protocols include X.400 and UUCP (Unix to Unix Copy Protocol).

administrator.  A user with administrative privileges for a server or multiple servers. See also Messaging Server administrator.

Allow filter.  A Messaging Server access-control rule that identifies clients that are to be allowed access to a service such as IMAP, POP, or SMTP. Compare Deny filter.

alternate address.  A secondary address for an account, generally a variation on the primary address. In some cases it is convenient to have more than one address for a single account.

anonymous access.  An optional type of access to a server, in which the user named anonymous is granted access without need for a password.

attribute.  An item of information contained in a tag, such as an HTML tag or a Messaging Multiplexor command tag.

AUTH.  An SMTP command enabling an SMTP client to specify an authentication method to the server, perform an authentication protocol exchange, and, if necessary, negotiate a security layer for subsequent protocol interactions.

authentication.  1) The process of proving the identity of a client user to the Netscape Messaging Server. 2)The process of proving the identity of the Netscape Message Server to a client or another server.

authentication certificate.  A digital file sent from server to client or client to server to verify and authenticate the other party. The certificate ensures the authenticity of its holder (the client or server). Certificates are not transferable.

AutoReply utility.  A utility that automatically responds to messages sent to accounts with the AutoReply feature activated. Every account in the Netscape Messaging Server can be configured to automatically reply to incoming messages.

backside port.  The port that the Messaging Multiplexor uses to communicate with the servers that contain the Multiplexor's clients' mailboxes. Compare listen port.

banner.  A text string displayed by a service such as IMAP when a client first connects to it.

base DN.  A distinguished name entry in the directory from which searches will occur. Also known as a search base. For example, ou=people, o=airius.com.

bind DN.  A distinguished name used to authenticate to the Directory Server when performing an operation.

body .  The main part of an email message. Although headers and envelopes must follow a standard format, the body of the message has a content determined by the sender--the body can contain text, graphics, or even multimedia.

capability.  A string, provided to clients, that defines the functionality available in a given IMAP service.

case tag.  A tag in the Message Field component of a UBE filter that specifies that matching should be case-sensitive.

certificate-based authentication.  Identification of a user from a digital certificate submitted by the client. Compare password authentication.

certificate database.  A file that contains a server's digital certificate(s). Also called a cert file.

certificate name.  The name that identifies a certificate and its owner.

cipher.  An algorithm used in encryption.

client.  A software entity that requests services or information from a server. Compare user.

CNAME record.  A type of record stored in a DNS server. A CNAME record maps a domain name alias to a domain name.

command tag.  A tag that appears in the mailmaster commands file; it defines actions to be performed by the Mailstone program.

comment character.  A character that, when placed at the beginning of a line, turns the line into a nonexecutable comment. For Netscape configuration files, it is the pound sign (#).

config_util.  A command line utility for making changes to configuration information stored in the directory server or in the local configuration file.

counter_util.  A command line utility for displaying all counters in a counter object.

daemon.  A Unix program that runs in the background, independent of a terminal, and performs a function whenever necessary. Common examples of daemon programs are mail handlers, license servers, and print daemons. On Windows NT machines, this type of program is called a service. See also service.

default log.  A Messaging Server log file that is produced by a service or utility other than the principal services Administration, SMTP, IMAP, and POP.

Deny filter.  A Messaging Server access-control rule that identifies clients that are to be denied access to a service such as IMAP, POP, or SMTP. Compare Allow filter.

deliver.  A command line utility for delivering mail to POP or IMAP folders.

directive.  An instruction between the opening and closing tags of a pair, such as a pair of HTML tags or a pair of command tags in the Mailstone utility's commands file.

directory lookup.  The process of searching the directory for information on a given user or resource, based on that user or resource's name or other characteristic.

directory service.  An application designed to manage information about people and resources within an organization. See also Lightweight Directory Access Protocol.

DNS.  See Domain Name System.

DNS alias.  A host name that the DNS server recognizes as pointing to a different host--specifically a DNS CNAME record. Machines always have one real name, but they can have one or more aliases. For example, www.airius.domain might be an alias that points to a real machine called realthing.airius.domain where the server currently exists.

DNS spoofing.  A form of network attack in which a client attempting to access or send a message to a server misrepresents its host name.

domain name.  A unique name that defines an administrative organization. Domains can contain other domains. Domain names are interpreted from right to left. For example, airius.com is both the domain name of the Airius Company and a subdomain of the top-level com domain. The airius.com domain can be further divided into subdomains such as corp.airius.com, and so on. See also host name and fully-qualified domain name.

Domain Name System (DNS).  The system used by machines on a network to associate standard IP addresses (such as 198.93.93.10) with host names (such as www.airius.com). Machines normally get this information from a DNS server. See also A record and MX record.

domain part.  The part of an email address that identifies the administrative authority responsible for the recipient.

encryption.  The process of disguising information so that it cannot be deciphered (decrypted) by anyone but the intended recipient.

enterprise network.  A network that consists of collections of networks connected to each other over a geographically dispersed area. The enterprise network serves the needs of a widely distributed company and is used by the company's mission-critical applications.

entry.  (1) In a directory, the collected information about a single person to resource. (2) In a log file, a line that represents one logged event.

envelope .  A container for information about the sender and the recipient of an email message. This information is not part of the message header. Envelopes are used by various email programs as messages are moved from place to place. Users see only the header and body of a message.

envelope field.  A named item of information, such as RCPT TO, in a message envelope.

envonly tag.  A tag in the Message Field component of a UBE filter that restricts the filter processing to the message envelope alone.

error handler .  A program that handles errors. In the Messaging Server, issues error messages and processes error action forms after the postmaster fills them out.

Error-Handler Action form.  A form sent to the postmaster account that accompanies a received message that the Messaging Server cannot handle. The postmaster fills out the form to instruct the server how to process the message.

error message.  A message reporting an error or other situation. Netscape Messaging Server generates messages in a number of situations, notably when it gets an email message that it can't handle. Others messages, called notification errors, are for informational purposes only.

ETRN.  An SMTP command enabling a client to request that the server start the processing of its mail queues for messages that are waiting at the server for the client machine. Defined in RFC 1985.

EXPN.  An SMTP command for expanding a mailing list. Defined in RFC 821.

extension library.  A shared library used to extend or override the capabilities of a plugin such as the UBE plugin.

extranet.  The part of a company intranet that customers and suppliers can access. See also intranet.

facility.  In a Messaging Server log-file entry, a designation of the software subsystem (such as Network or Account) that generated the log entry.

filter.  See UBE filter, Allow filter, Deny filter.

filter.cfg.  The file that holds all the UBE filter rules; used by the UBE plugin.

filter.opt.  A file that controls certain aspects of the behavior of the UBE plugin.

firewall.  A network configuration, usually both hardware and software, that forms a barrier between networked computers within an organization and those outside the organization. A firewall is commonly used to protect information such as a network's email, discussion groups, and data files within a physical building or organization site.

folder.  A named collection of messages. Folders can contain other folders. See also personal folder and shared folder.

forwarding.  The act that occurs when an MTA sends a message delivered to a particular account to one or more new destinations as specified by the account's attributes. Forwarding may be configurable by the user. See also routing.

FQDN.  See fully-qualified domain name.

fully-qualified domain name (FQDN).  The unique name that identifies a specific Internet location. See also domain name.

greeting form.  A message usually sent to users when an account is created for them. This form acts as confirmation of the new account and verification of its contents. The greeting form also instructs users on how to change information related to their mail account. During installation, system administrators have the option of deciding whether to send greeting forms to users.

hashdir.  A command line utility for determining which directory contains the message store for a particular user.

header.  The portion of an email message that precedes the body of the message. Headers contain information useful to email programs and to users trying to make sense of the message: they tell whom the message is for, who sent it, when it was sent, and what it is about. Headers must be written according to the SMTP protocol so that email programs can read them.

header field.  A named item of information, such as From: or To:, in a message header.

hop.  A transmission between two computers.

host.  The machine on which one or more servers reside.

host name.  The name of a particular machine within a domain. The fully qualified host name consists of two parts: the host name and the domain name. For example, mail.airius.com is the machine mail in the domain airius.com. Host names must be unique within their domains. Your organization can have multiple machines named mail, as long as the machines reside in different subdomains; for example, mail.corp.airius.com and mail.field.airius.com. Host names always map to a specific IP address. See also domain name, fully-qualified domain name, and IP address.

host name hiding.  The practice of having domain-based email addresses that don't contain the name of a particular host.

hub.  A host that acts as the single point of contact for the system. When two networks are separated by a firewall, for example, the firewall computer often acts as a mail hub.

IMAP4.  See Internet Message Access Protocol Version 4.

ImapMMP.config.  A configuration file that defines an IMAP4 instance of the Messaging Multiplexor.

ImapMMP.sh.  A Unix shell script that sets configuration parameters and executes the IMAP Messaging Multiplexor.

ImapProxy.  The executable file for the IMAP Messaging Multiplexor.

imscripter.  A command line utility that talks to an IMAP server. You can use this utility to execute a command or batch of commands on IMAP folders.

installation directory.  The directory into which the binary (executable) files of a server are installed. For the Messaging Server, it is a subdirectory of the server root: serverRoot/bin/msg/. Compare instance directory, server root.

instance.  A separately executable configuration of a server or other software entity on a given host. With a single installed set of binary files, it is possible to create multiple instances of Netscape servers that can be run and accessed independently of each other.

instance directory.  The directory that contains the files that define a specific instance of a server. For the Messaging Server, it is a subdirectory of the server root: serverRoot/msg-instanceName/, where instanceName is the name of the server as specified at installation. Compare installation directory, server root.

Internet.  The name given to the worldwide network of networks that uses TCP/IP protocols.

Internet Message Access Protocol Version 4 (IMAP4).  A standard protocol that allows users to be disconnected from the main messaging system and still be able to process their mail. The IMAP specification allows for administrative control for these disconnected users and for the resynchronization of the users' message store once they reconnect to the messaging system.

Internet Protocol (IP).  The basic network-layer protocol on which the Internet and intranets are based.

intranet.  A network of TCP/IP networks within a company or organization. Intranets enable companies to employ the same types of servers and client software used for the World Wide Web for internal applications distributed over the corporate LAN. Sensitive information on an intranet that communicates with the Internet is usually protected by a firewall. See also firewall and extranet.

IP.  See Internet Protocol.

IP address.  A set of numbers, separated by dots, such as 198.93.93.10, that specifies the actual location of a machine on an intranet or the Internet.

key database.  A file that contains the key pair(s) for a server's certificate(s). Also called a key file.

label.  A component of a UBE filter; it provides a named destination for the actions of other filters.

LDAP.  See Lightweight Directory Access Protocol.

LDAP Data Interchange Format (LDIF).  The format used to represent Directory Server entries in text form.

LDAP search string.  A string with replaceable parameters that defines the attributes used for directory searches. For example, an LDAP search string of "uid=%s" means that searches are based on the user ID attribute.

LDIF.  See LDAP Data Interchange Format.

level.  A designation of logging verbosity, meaning the relative number of types of events that are recorded in log files. At a level of Emergency, for example, very few events are logged; at a level of Informational, on the other hand, very many events are logged.

Lightweight Directory Access Protocol (LDAP).  Directory service protocol designed to run over TCP/IP and across multiple platforms. A simplification of the X.500 Directory Access Protocol (DAP) that allows a single point of user and group account management across Netscape servers. The Netscape Directory Server uses the LDAP protocol.

listen port.  The port that a server uses to communicate with clients and other servers. The Messaging Multiplexor can use both a listen port and a separate backside port.

local part.  The part of an email address that identifies the recipient. See also domain part.

log directory.  The directory in which all of a service's log files are kept.

log expiration.  Deletion of a log file from the log directory after it has reached its maximum permitted age.

log rotation.  Creation of a new log file to be the current log file. All subsequent logged events are to be written to the new current file. The log file that was the previous current file is no longer written to, but remains in the log directory.

mailbox .  See folder.

mail client.  The programs that help users send and receive email. This is the part of the various networks and mail programs that users have the most contact with. Mail clients create and submit messages for delivery, check for new incoming mail, and accept and organize incoming mail.

mailclient.  The main program used by the Mailstone utility.

mailclient commands file.  A configuration file that defines the commands to be executed by the Mailstone utility.

mail exchange record .  See MX record.

mailmaster.  A Perl script used by the Mailstone utility to control execution of the mailclient program on multiple client hosts.

mailmaster client.  The client machine on which the mailmaster script executes in a Mailstone test configuration.

mailmaster configuration file.  A file that defines test parameters for the Mailstone utility.

Mailstone.  A utility for performing stress tests. The Mailstone utility enables you to perform capacity planning by testing the ability of your mail server to function properly under maximum loads.

Management Information Base (MIB).  A database containing data about managed network objects.

master agent.  The SNMP agent that exchanges information between the Network Management station (NMS) and its subagents. See also subagent.

match criterion.  A component of a UBE filter; it is a string or expression that represents an envelope or header phrase (such as "Easy Money") to be matched against incoming messages.

mboxutil.  A command line utility for managing mail folders.

MD5.  A message digest algorithm by RSA Data Security. MD5 can be used to produce a short digest of data that is unique with high probability. It is mathematically extremely hard to produce a piece of data that produces the same message digest email.

message .  The fundamental unit of email, a message consists of a header and a body and is often contained in an envelope while it is in transit from the sender to the recipient.

message delivery.  When the MTA delivers a message to a local recipient (a mail folder or a program).

message field.  A component of a UBE filter; it specifies the specific envelope or header item (such as Subject:) whose contents are to be matched against incoming messages.

Message Handling System (MHS).  A group of connected MTAs, their user agents, and message stores.

message queue.  The directory where messages accepted from clients and other mail servers are queued for delivery (immediate or deferred).

message quota.  A limit defining how much disk space a particular folder can consume.

message store.  The database of all locally delivered messages for a Messaging server instance. Messages can be stored on a single physical disk or stored across multiple physical disks.

message store partition.  A message store or subset of a message store residing on a single physical file system partition.

Message Transfer Agent (MTA).  A specialized program for routing and delivering messages. MTAs work together to transfer messages and deliver them to the intended recipient. The MTA determines whether a message is delivered to the local message store or routed to another MTA for remote delivery.

Messaging Multiplexor.  A specialized Netscape Messaging Server that acts as a single point of connection to multiple mail servers, facilitating the distribution of a large user base across multiple mailbox hosts.

Messaging Server administrator.  The administrator whose privileges include installation and administration of a Netscape Messaging Server instance.

MHS.  See Message Handling System.

MIB.  See Management Information Base.

MIME.  See Multipurpose Internet Mail Extension.

mmp-setup.  The Unix filename for the Messaging Multiplexor installer.

MoveUser.  A command line utility for moving messages in a user's mail folder from one Messaging Server to another.

msgalarmproc.  A command line utility for monitoring disk usage and server response time.

MTA.  See Message Transfer Agent.

MTA hop.  The act of routing a message from one MTA to another.

Multiplexor.  See Messaging Multiplexor.

Multipurpose Internet Mail Extension (MIME).  A protocol you can use to include multimedia in email messages by appending the multimedia file in the message. Because not all mail clients support MIME, you should make sure that the message recipient has a MIME-enabled mail client.

MX record.  A type of record stored in a DNS server that maps a domain name to a host name.

net mask.  A 32-bit value used in conjunction with an IP address to separate the network and subnet IDs from the host ID.

Netscape administrator.  The administrator whose privileges include installation and administration of all Netscape servers, including the Netscape Directory Server.

Netscape Console.  The administrator interface from which you administer all Netscape servers.

Netscape Setup.  The installation program for all Netscape servers and for Netscape Console.

next-hop list.  A list of adjacent systems a mail route uses to determine where to transfer a message. The order of the systems in the next-hop list determines the order in which the mail route transfers messages to those systems.

notification message.  A type of message, sent to the postmaster account by the Messaging Server, that is for information al purposes and requires no action from the postmaster. Compare error message.

NscpMsg (Unix only).  A command line utility for starting and stopping the Netscape Messaging Server and for running recovery utilities.

nsfilter.  The shared library file that contains the UBE plugin.

partition.  See message store partition.

password authentication.  Identification of a user through user name and password. Compare certificate-based authentication.

pattern.  A string expression used for matching purposes, such as in Allow and Deny filters.

personal folder.  A folder that can be read only by the owner. See also shared folder.

plain text authentication.  See password authentication.

plugin.  A server extension program, implemented on the Messaging Server as a shared library that uses the Messaging Server Plugin API.

POP3.  See Post Office Protocol Version 3.

PopMMP.config.  A configuration file that defines a POP3 instance of the Messaging Multiplexor.

PopMMP.sh.  A Unix shell script that sets configuration parameters and executes the POP3 Messaging Multiplexor.

PopProxy.  The executable file for the POP Messaging Multiplexor.

port number.  A number that specifies an individual TCP/IP application on a host machine, providing a destination for transmitted data.

postmaster.  By convention, an account used to communicate with the person (or people) responsible for maintaining a messaging server.

Post Office Protocol Version 3 (POP3).  A protocol that provides a standard delivery method and that does not require the message transfer agent to have access to the user's mail folders. Not requiring access is an advantage in a networked environment, where often the mail client and the message transfer agent are on different computers.

process.  A self-contained, fully functional execution environment set up by an operating system. Each instance of an application typically runs in a separate process. Compare thread.

qconvert.  A command line utility for converting the Netscape Messaging Server 3.x message queue to the 4.0 MTA format.

quota.  A command line utility for viewing reports about and fixing message quota usage. See also message quota.

RC2.  A variable key-size block cipher by RSA Data Security.

RC4.  A stream cipher by RSA Data Security. Faster than RC2.

readership.  A command line utility for collecting readership information on mail folders.

reconstruct.  A command line utility for reconstructing mail folders.

regular expression.  A text string that uses special characters to represent ranges or classes of characters for the purpose of pattern matching.

routing.  The act of transferring a message from one MTA to another when the first MTA determines that the recipient is not a local account, but might exist elsewhere. Routing is normally configurable only by a network administrator. See also forwarding.

routing tables.  The internal databases that hold the information about message originators and recipients. See also SMTP mail routing table.

RUN action.  A special action of the UBE plugin; it calls external programs that extend the plugin.

schema.  Definitions of the types of information that can be stored as entries in the Netscape Directory Server. When information that does not match the schema is stored in the directory, clients attempting to access the directory might be unable to display the proper results.

search base.  See base DN.

Secure Sockets Layer (SSL).  A software library establishing a secure connection between two parties (client and server) used to implement HTTPS, the secure version of HTTP.

security-module database.  A file that contains information describing hardware accelerators for SSL ciphers. Also called secmod.

sendmail.  A common MTA used on Unix machines. In most applications, the Netscape Messaging Server can be used as a dropin replacement for sendmail. Netscape provides a set of sendmail migrations tools.

server instance.  The directories, programs, and utilities representing a specific server installation.

server root.  The directory into which all Netscape servers associated with a given Administration Server on a given host are installed. Typically designated serverRoot. Compare installation directory, instance directory.

service.  (1) A background process on Windows NT that does not have a user interface. Netscape servers on Windows NT platforms run as services. Equivalent to daemon. (2) A function provided by a server. For example, the Netscape Messaging Server provides IMAP, POP, and SMTP services.

session.  An instance of a client-server connection.

shared folder.  A folder that can be read by more than one person. Compare personal folder.

Simple Mail Transfer Protocol (SMTP).  The email protocol most commonly used by the Internet and the protocol supported by the Netscape Messaging Server.

Simple Network Management Protocol (SNMP).  A network protocol that allows administrators to monitor server processes remotely on SNMP-compatible servers through the use of SNMP station software.

SIZE.  An SMTP command enabling a client to declare the size of a particular message to a server. The server may indicate to the client that it is or is not willing to accept the message based on the declared message size; the server can declare the maximum message size it is willing to accept to a client. Defined in RFC 1870.

SMTP.  See Simple Mail Transfer Protocol.

smtpAccept.  The stage of SMTP message processing that involves accepting messages sent from clients or other servers.

smtpDeliver.  The stage of SMTP message processing that involves transferring messages to other servers.

SMTP mail routing table.  Provides a way to redirect mail based on the domain to which it is being sent. Each entry in the SMTP Mail Routing table consists of a pattern and a domain. Before sending a message, the destination domain is compared to the patterns in the table. If a match is found, the destination host is replaced by the domain corresponding to the pattern that matched.

SNMP.  See Simple Network Management Protocol.

spoof message.  A message that the Messaging Multiplexor can send to a user when the Multiplexor cannot connect to the user's mailbox server.

spoofing.  Misrepresentation of its host name, domain name, or IP address by a client attempting to gain access to or send a message to a server.

SSL.  See Secure Sockets Layer.

subagent.  An SNMP agent that gathers information regarding network activity of a particular device, such as the Netscape Messaging Server.

subdomain.  A portion of a domain. For example, in the domain name corp.airius.com, corp is a subdomain of the domain airius.com. See also host name and fully-qualified domain name.

subnet.  The portion of an IP address that identifies a block of host IDs.

TCP.  See Transmission Control Protocol.

TCP/IP.  See Transmission Control Protocol/Internet Protocol.

thread.  A lightweight execution instance within a process.

Transmission Control Protocol (TCP).  The basic transport protocol in the Internet protocol suite that provides reliable, connection-oriented stream service between two hosts.

Transmission Control Protocol/Internet Protocol (TCP/IP).  The name given to the collection of network protocols used by the Internet protocol suite. The name refers to the two primary network protocols of the suite: TCP (Transmission Control Protocol), the transport layer protocol, and IP (Internet Protocol), the network layer protocol.

UA.  See user agent.

UBE.  See Unsolicited Bulk Email.

UBE filter.  A rule that defines how messages that fit a certain match criterion are to be handled. See also Unsolicited Bulk Email (UBE).

UBE plugin.  An SMTP plugin that applies UBE filters to incoming messages.

Unsolicited Bulk Email (UBE).  Unrequested and unwanted email, sent from bulk distributors, usually for commercial purposes.

user.  (1) A person that makes use of computer software. (2) An account for accessing a server, maintained as an entry on a directory server.

user agent (UA).  The client component, such as Netscape Communicator, that allows users to create, send, and receive mail messages.

virtual domain.  A domain name added by the Messaging Multiplexor to a client's user ID for LDAP searching and for logging into a mailbox server.

VRFY.  SMTP command for verifying a user name. Defined in RFC 821.

wildcard.  A special character in a search string that can represent one or more other characters or ranges of characters.