Chapter 1: Introduction to GroupWise Internet Agent
Welcome to the GroupWise* Internet Agent Guide. This guide will help you understand how GroupWise Internet Agent adds complete Internet messaging services to your existing GroupWise system, and will help you install and configure the GroupWise Internet Agent software. In this first chapter you will find basic information about electronic messaging systems, the Internet, open Internet standards like SMTP, MIME, POP3, IMAP4, and LDAP, and the services of GroupWise Internet Agent that support these standards. After you have read this introductory chapter, you can move on to Chapter 2: Prepare to Install Internet Agent.
Choose from the following list of topics to learn more about Internet messaging and the capabilities of GroupWise Internet Agent.
There are many different electronic messaging systems currently available. The products range from legacy systems such as OfficeVision** and VMS Mail**, to systems tightly integrated with specific network operating systems such as UNIX Mail, to a variety of LAN-based messaging systems such as GroupWise, Lotus cc:Mail**, and Microsoft Mail**. All of these electronic messaging systems are proprietary messaging systems, meaning they do not work directly with each other.
Organizations and people need to be able to communicate with other organizations and people, regardless of the messaging system they are each using. Due to the large number of proprietary messaging systems, a tremendous need for a common interface between these various messaging systems exists. The Internet offers a solution with global connection capabilities and open standards for message transmission and message formatting. GroupWise Internet Agent lets you take advantage of the Internet's inherent messaging capabilities by offering services at both the client and server that support those open standards. Before we discuss the features of GroupWise Internet Agent, it might be helpful to learn something about the background of the Internet itself.
The Internet began in the early 1970's when the U.S. Department of Defense created a network called ARPAnet. The purpose of the ARPAnet was to build a computer network that could withstand an enemy attack without serious disruption to the flow of sensitive information. The ARPAnet network design did not include a central hub or a command center that, if disabled, would compromise the entire network. Instead, Internet communication was configured between a source and a destination computer. The network's sole function was to transport information, the path information took along the network was unimportant. If one segment of the network went down, information could simply be routed along another path.
ARPAnet eventually expanded to include universities, government agencies, and research facilities. Each organization recognized the importance of an open communication system that did not rely on identical computer platforms.
Today, as we are all aware, the Internet has evolved to become the Information Superhighway, allowing access to infinite amounts of information. Routing possibilities increase as the Internet proliferates, supplying a reliable yet decentralized flow of information around the world.
Internet
Communication Protocols
The Internet uses communication
protocols known as the Internet Protocol Suite that allows sending
computers to communicate directly with receiving computers regardless of
the path. TCP/IP is the main protocol in this protocol suite. The
Transmission Control Protocol, TCP, divides information into packets
(small pieces of data). The Internet Protocol, IP, labels each packet with
the sender's and the recipient's addresses. The Internet Protocol then
routes the packets to the correct recipient location.
Packets may take different routes and may arrive out of sequence. At the receiving end, IP collects the packets. When all packets have arrived, they are reassembled by TCP and passed to the appropriate application for delivery. If all the packets do not arrive, TCP requests the sender to resend the information.
Internet e-mail is transmitted using a communication protocol called the Simple Mail Transfer Protocol, or SMTP. SMTP utilizes a TCP/IP connection. SMTP resolves the recipient's address and delivers the e-mail message.
There are several open Internet standards or protocols used to define both the formatting of Internet messages and the sending and receiving of those messages over the Internet. SMTP (Simple Mail Transfer Protocol), RFC-822 (Request For Comment-822), and MIME (Multipurpose Internet Mail Extensions) are some of the most common standards.
SMTP is the mail transport protocol used to send both RFC-822 and MIME format messages across the Internet. RFC-822 is a limited mail format that has been used for many years. MIME is a new extension of the RFC-822 format that is backward-compatible with RFC-822. MIME is more versatile than RFC-822 and allows for more sophisticated formatting.
RFC-822
Message Format Standard
RFC-822 provides for the
transmission of US-ASCII single-part messages on the Internet. To send
anything except text, you must encode (convert binary data to ASCII data)
the files you are sending. The encoding scheme called UUencode is most
often used with RFC-822 and has variations that can hamper decoding of a
transmitted file. SMTP is often incorrectly used synonymously with
RFC-822. SMTP, which stands for Simple Mail Transport Protocol, is the
mail transport protocol while RFC-822 and MIME are mail message formats.
MIME Message
Format Standard
MIME overcomes RFC-822 mail limitations by
providing standard encoding schemes, transmission of non US-ASCII text,
and accommodation of multipart messages. MIME is also backward-compatible
with RFC-822. A user who receives a MIME format message but lacks a
MIME-compliant e-mail program can still read the message. The GroupWise
Internet Agent program supports SMTP mail transfer in both RFC-822 and
MIME formats.
GroupWise Internet Agent Support for Internet Standards
GroupWise Internet Agent is a versatile Internet messaging solution that supports the open standards of the Internet. This support includes Internet message and communication protocols such as SMTP and MIME, as well as POP3, LDAP, IMAP4.
The definition of a gateway is an agent that translates packets from one kind of network protocol to another. Internet Agent performs a similar function for e-mail messaging over the Internet. Internet Agent is an agent that allows communication between GroupWise and other messaging systems via the Internet. It translates e-mail messages from the RFC-822/MIME format to the GroupWise message format, and vice-versa.
For an inbound message, Internet Agent receives the message from the foreign messaging system, converts it to GroupWise format, then passes the message to the GroupWise Message Transfer Agent for delivery to the recipient. For an outbound message, the GroupWise user sends the message which is picked up by the GroupWise Message Transfer Agent. The Message Transfer Agent passes the message to Internet Agent for conversion to the format of the foreign messaging system and passes the message to that system for delivery to the recipient.
POP3 Server
Support
GroupWise Internet Agent has the capability to
function as a POP3 server. When POP3 Services are enabled, users can
download their e-mail messages from the GroupWise Universal Mailbox to a
POP3 client application such as Netscape Mail** or Eudora Pro**.
IMAP4 Support
Internet
Agent also supports the IMAP4 messaging standard and can function as an
IMAP4 server. Using Internet Agent's IMAP4 Services, GroupWise users can
download their GroupWise messages to a third-party IMAP4-compliant client
application such as Netscape Mail.
LDAP Support
Internet
Agent can function as an LDAP server. LDAP support allows GroupWise users
the ability to perform address look-ups in LDAP-compliant directories
outside of the GroupWise Address Book system. Additionally, the GroupWise
Address Book is opened to LDAP-based searching from an LDAP-compliant
e-mail client.
SMTP Dial-up
Feature
If your organization does not require a permanent
Internet connection, you can use the SMTP Dial-up feature of Internet
Agent to conveniently connect to the Internet to send and receive e-mail
messages on-demand. After you activate and configure a periodic dialing
profile, the Internet Agent will link to your ISP and check for new
incoming and outgoing SMTP-compliant Internet messages.
GroupWise Internet Agent Features
GroupWise Internet Agent provides GroupWise users with the ability to send and receive Internet e-mail messages and attachments. Internet Agent also includes the following features:
SMTP/MIME
Service
Allows you to send and receive e-mail with standard
encoding on attachments, international character sets, and multipart
messages. Multimedia e-mail with graphics, sound, and video may also be
exchanged.
POP3 Service
Allows
you to download messages from your GroupWise 5 post office to a POP3
client application such as a web browser's e-mail program or a Telnet
application. Internet Agent acts as the POP3 server, providing a TCP
connection between the user's GroupWise 5 post office and a POP3 client.
Accessing the GroupWise 5 post office via Internet Agent' POP3 server
capability, the user can retrieve their e-mail messages and manage them
through User ID login options.
LDAP and
IMAP4 Services
GroupWise Internet Agent supports the open,
evolving standards of Internet messaging including LDAP and IMAP4.
SMTP Dial-up
Service
Internet Agent adds the functionality of an SMTP
dial-up feature. This can be useful when your system does not meet the
requirements of a dedicated Internet connection, or when you prefer not to
have a permanent Internet connection. With the SMTP-Dialup feature, you
can periodically check the message store without having to maintain a
permanent link.
Multiple
Threading
Multiple threading allows more than one send or
receive process to be running concurrently. You can configure the number
of threads to enhance the speed and performance of the Internet Agent. The
number of thread switches are set separately for the SMTP/MIME service,
and the POP3 service.
Internet
Header
On incoming Internet messages the header information
is automatically placed in an attachment.
Multiple
Foreign Names
Internet Agent may be seen as one or more
Internet host addresses if user aliases, Internet Agent aliases, or post
office aliases are used. Multiple foreign names can also be used to help
implement a firewall or central mail hub.
Flexible
Addressing
Internet Agent offers full GroupWise addressing
support includes system groups, nicknames, and individual users.
Internet
Users in Address Book
Internet users may be added to the
GroupWise Address Book so users won't have to remember long Internet
addresses.
Connect to
Other GroupWise Systems Through the Internet
Using
passthrough addressing you can connect to other GroupWise systems anywhere
on the Internet and have access to all of the GroupWise features. The
Internet simply becomes a mail transport medium for GroupWise.
Merge With
Other GroupWise Systems Through the Internet
Using
passthrough addressing you can merge and administer other GroupWise
systems anywhere on the Internet.
Access
Control
The Internet Agent program includes security
capabilities called Access Control that let administrators control inbound
and outbound messages. Access Control can help you reduce costs and
provide added security.
Accounting
The
accounting feature provides inbound and outbound tracking of messages
passing through Internet Agent. This lets administrators track how
Internet Agent is being used.
Mail
Hub/Smart Host Server
Internet Agent can function as an
SMTP mail hub, or smart-host, to resend messages it receives that should
go to another host.
SNMP-compliant
(NLM Version)
The NLM version of Internet Agent can be
managed by any SNMP-compliant network manager, such as Novell's
ManageWise* network management suite.
SMP Support
(NLM Version)
SMP, or Symmetric Multi-Processor, support
lets Internet Agent take advantage of a server machine with multiple
processors.
DNS Name
Resolution and MX Record Aware
Internet Agent does not
require a smart host. It can perform IP address resolution directly with a
Domain Name System and is MX record aware.
Ways to Use GroupWise Internet Agent
You can use GroupWise Internet Agent in the following ways.
Changes from Previous Versions
The following items have been changed or added to GroupWise Internet Agent from previous versions of the SMTP/MIME Gateway.
MIME Support
Internet Agent now supports Multipurpose Internet Mail Extensions, or MIME. MIME provides a means of sending multimedia e-mail and international character sets. Internet Agent defaults to MIME format.
POP3 Server Support
Internet Agent lets you download messages from your GroupWise 5 system to a POP3 Client such as a web browser's e-mail program or a Telnet application. GroupWise Internet Agent acts as the POP3 Server host which provides a TCP connection between the user's GroupWise 5 post office and a POP3 Client allowing the user to retrieve and, through User ID login options or POP3 commands, manage their e-mail.
Multiple Threading
This is a new feature in GroupWise Internet Agent, a GroupWise 5 level program. Multiple threading allows for more than one send or receive process to be running concurrently. You can configure the number of threads to enhance the speed and performance of Internet Agent. However, increasing the number of threads also uses more computer resources like memory and CPU time.
Access Control
The GroupWise administrator can now control message sizes as well as who can receive and send e-mail messages through Internet Agent. By creating a Class of Service, which defines access to the various services of Internet Agent, and assigning users to a Membership List, the system administrator can customize access privileges to fit the needs of the organization.
Undeliverable Messages Are Now Returned
If a message sent through Internet Agent to an Internet address is undeliverable, then the whole message will be returned to the sender as part of the undeliverable message. If the message becomes undeliverable within the GroupWise system, only the subject line will be returned.
Preamble Files
An administrator-configurable ASCII preamble file called PREAMBLE.TXT is installed in the Internet Agent root directory. It will be included with any MIME multi-part message prior to the boundaries. This file will display for any recipient who lacks a MIME-compliant mail reader. The PREAMBLE.ALL file is also installed. It contains the PREAMBLE.TXT text in various languages.
MIME and RFC-822 Switches Added
These switches tell Internet Agent to send messages to a domain in MIME or RFC-822 format. This allows users to choose which encoding scheme to use.
Multinational Character Set Support
As part of the MIME specifications, multinational character sets may be used in the creation or interpretation of MIME mail messages. ISO-8859-1-9 are supported. For example, if you compose a message using characters from the WordPerfect Cyrillic character set, Internet Agent will utilize the MIME Content-type charset parameter ISO-8859-5 (Latin/Cyrillic alphabet) in describing the message. When received by a MIME-compliant mail program (or another GroupWise Internet Agent system), the message will be displayed in the proper character set. Internet Agent also supports ISO-2022-JP, KR, and CH multi-byte character sets for use with Japanese, Korean and Chinese systems.
Smart Host Ability
Internet Agent can function as a smart host that can perform mail routing. It will route messages it receives that are supposed to be delivered to another destination host.
Automatic Shutdown
The administrator can automatically shut down the Internet Agent program without having to use the exit keys on the Operation Screen. Automatic shutdown can be accomplished by sending a special e-mail message to Internet Agent or by using a SHUTDOWN file.
Language Support in Configuration Files
Many of the configuration files have been translated into languages other than English. You can delete any language portion that is not needed for your configuration without affecting Internet Agent.
* Novell trademark. ** Third-party trademark. See Trademarks for more information.