Sunday, December 5, 2010

CH A P T E R 29

Electronic Messaging
Systems
Electronic messaging has transformed commerce and our personal lives to such
a degree that it is difficult to remember when we did not have instantaneous message
and file transfer at our fingertips. E-mail is the most frequently used application
on the Internet, which is rather astounding considering the popularity of
the Web, which occupies second place. E-mail is revolutionizing the way people
communicate. No longer is it necessary to fax a document, wait for the postal service,
or even walk down the hall to another office. Information can be transferred
instantaneously between any computers that have access to an e-mail server,
either a public server or a private server attached to the office LAN.
The world has had e-mail for many years, but it needed the Internet to bring
the ease of use and near-universal connectivity that we now have. The first e-mail
systems were isolated islands. Some were host based, residing on a mainframe or
minicomputer, and useful only for internal communications. For example, IBM
provided PROFS or SNADS for users operating on an IBM mainframe and the
UNIX operating system provided e-mail as a standard feature. Communicating
outside the office network, however, was neither easy nor In expensive. Valueadded
carriers such as AT&T American Telephone and Telegraph Corporation and MCI media control interface provided e-mail as did database companies
such as AOL America On Line and CompuServe on-line information service provider. If you knew the addressing protocol, you could
usually transmit messages to someone on another network, but it was difficult to
be sure the message would arrive.
E-mail was one of the earliest applications for the Internet. Simple Mail
Transfer Protocol was devised to permit two UNIX computers connected with
IP to interact with each other’s internal mail application. SMTP Simple Mail Transport Protocol uses a text-based
dialogue between computers to transfer mail.
The ITU-T’ answer to e-mail is the X.400 Message Handling System (MHS)
protocol. Public e-mail systems such as those operated by the major IXC long-distance telephone company s and
most international carriers use X.400 and it is the common language that many proprietary systems speak. In contrast to SMTP, X.400 is not simple. It is, however,
an international standard that can operate between companies and across borders.
Before the Department of Defense turned over change direction; exchange; submit; (Slang) rob
the Internet to private operation,

X.400 was the main methodof interconnecting õîëáîãäîõ otherwise incompatible systems.
Both X.400 and Internet e-mail have similar features
The earliest versions did not
support file transfer, but today you can attach any type of information such as
voice and video clips, documents, and spreadsheets spreadsheet n. accounting program for a computer; chart with multiple columns used in such a program
to an e-mail message with
little more effort than a mouse click.
One of the major attractions attractionn. inward pull; something which excites interest and attention
of Internet e-mail is the fact that practically anyone
can get an address that is easy to use and remember , and if you are willing to
put up with
advertising, it may even be free. The other major value of e-mail is its
inherently
asynchronous nature. Messages are stored in a server until the recipient
is ready to pick them up. Internet e-mail is a client-server application. The
client software resides, on desktop computers and the servers are either internal to
a company or operated by an ISP Internet Service Provider. Internal e-mail servers receive mail for the
organization

and distribute it internally in the interior, on the inside, from the inside; mentally, usually after checking it for viruses.
To some

degree, e-mail and voice mail have similar characteristics. Both


permit information transfer without the simultaneous availability of the participants.
Both work across time zones. They can broadcast messages to defined user
groups, and with unified messaging the two are linked to enable users to choose
the device that they want to use to retrieve messages. Voice mail is more transitory
than e-mail, which retains a written record of the communication. This is a
major advantage of e-mail, except for those who later need deniability.
E-mail has transcended organizational boundaries . Individuals throughout
the world exchange e-mail messages at a cost that is practically zero. Instant messaging
(IM), once the province of teenagers, is moving into the enterprise, where
short messages can pop up on computer screens, wireless phones, or PDAs Personal Digital Assistant. This
chapter discusses some of the applications and the protocols under which e-mail
operates. We review the issues involved in implementing such applications as
electronic mail, IM, electronic data interchange (EDI) Electronic Data Interchange , and data interchange
between similar applications such as word processors special computer program that allows one to edit documents that have been entered into the computer.
MESSAGING SYSTEM OVERVIEW
The terms messaging system and e-mail are often used interchangeably, but to be
strictly

accurate , e-mail is only one of the types of information that a messaging
system can transport. For example, scheduling, calendaring, forms, workflow,
inventory , and business documents that are transported over EDI are examples of
applications that can be built on a messaging system. Some form of e-mail exists
for nearly every computer operating system in existence, and nearly every desktop
computer today runs an e-mail client.


Figure 29-1 is a generic
diagram of an electronic messaging system. Message
transfer agents (MTAs) are the servers that move e-mail across the backbone spine; bone marrow; strength of character, determination; physical infrastructure of the Internet (Computers network.
The backbone can be a public backbone such as the Internet or a private
F I G U R E 29-1
A Generic Messaging System
network running IP or some other protocol. The user agent (UA), also known
as the client, is used at both ends of a mail system to create , send, receive, and
manage messages. Microsoft Outlook, for example, is a popular client. Many
others are available; some can be downloaded without cost . The client
software
links with one or more MTAs to transfer messages. The client has four main
functions:
_ Lists headers of all of the messages in your mailbox. The header identifies
the subject, sender, time, date, and message size.
_ Provides a method of opening and reading messages and file attachments.
_ Provides a structure

for creating and sending messages.
_ Provides a structure for attaching files.
Aclient wishing to send a message first links to a server that recognizes
it as
an authorized
user. The server identifies the client by user name and password,
and then gives the client permission
to transfer the message. If the addressee
resides on the same server, the message is moved to the addressee’s mailbox. If
the addressee is not local , the server queries DNS to find the address of the
addressee’s SMTP server. Then the message is forwarded across the backbone. All
of the MTAs in the message transfer process must be capable of supporting all of
the features the client requested or the transfer will fail. For example, if the messaging
system is capable of carrying voice clips, but one server in the chain lacks
that capability, the feature will be unavailable. If the addressee is unidentified or
unreachable, the server sends an e-mail message to the sender. In the Internet mail system, the MTA resides in ISPs’ mail servers. When
client software is set up, it contains
the name and address of the mail server, which
could be an internal server running software such as Microsoft Exchange, or it
could be an ISP’s server. Small organizations and individual users normally cannot
justify the cost and complexity of a mail server, so they use the ISP’s server
and set up their client software to check for mail periodically.
The mail server typically runs two different applications: the SMTP server
for sending outgoing mail, and the post office server for inbound mail. Post Office
Protocol 3 (POP3) is a simple protocol that transfers mail to the client without
retaining retain
a copy. Once mail is read from a POP3 Post Office Protocol
n. protocol for receiving electronic mail from a central POP server (Computers)
server, it is deleted, although the
user can save it on the client computer. An Internet Message Access Protocol
(IMAP) server retains messages on the post office server until they are deleted.
The post office server maintains a list of all clients’ user names and passwords for
Retrieving mail. Message transfer between incompatible

MTAs must go through a
gateway, which translates the protocols of the systems. For example, gateways
transfer mail between the Internet and X.400.
THE X.400 MESSAGING PROTOCOL
ITU-T has adopted X.400 as its standard message-handling protocol. X.400 is more
popular in Europe than in the United States, where Internet mail over SMTP Simple Mail Transport Protocol -
became the accepted method of e-mail communications. Some international carriers
implement all or part of X.400. The protocol provides for both a UA and an
MTA, but many carriers choose to provide a proprietary user interface.
The power of X.400 is procured at a sacrifice of simplicity . It is a complex system
to set up and administer which is the reason that many host-based and proprietary
mail systems use their own protocol and use X.400 for message exchange
between systems. X.400 is an open architecture , but it is impractical
for LAN
application because of its overhead and complex addressing method of accessing network resources scheme. Each X.400
MHS is an independent
Domain and these must be connected by agreement
between the carriers. If you subscribe to mail from one carrier, you will be able to
send mail to customers of another carrier only if they have established an interconnection
agreement
and a gateway to pass messages. Many X.400-to-Internet
mail gateways are in use because Internet mail is so much more prevalent.
X.400 Addressing
X.400 uses a multilevel hierarchical address as illustrated in Figure 29-2. The character
string can be daunting until one understands its structure. At the top level is
the root, followed by country, which is a mandatory part of the address. The next
level can be A for an administrative domain or P for a private domain. An administrative
domain is usually a service provider such as AT&T Mail. Large companies
may use a private domain in lieu of a service provider. At the next level is
F I G U R E 29-2
X.400 Addressing Structure
organization unit (OU), which is a unique identifier referring to a company’s private
messaging system. Below the organization companies may identify localities
and organizational units of several levels. The lowest inferior
level is the CN (common
name), which can optionally be stated as given name (G) and surname (S).
The X.400 addressing system is flexible, but verbose. The protocol allows for
address aliasing, which can provide a shortcut address across directory levels.
Users are unlikely to understand the addressing well enough to create their own
Aliases , so expert assistance

may be needed. Most effective UAs provide shortcut
addresses.
X.500 Directory Service for X.400
ITU’s X.500 protocol contains information about X.400 addresses. The directory is
hierarchically organized along X.400 lines by country, organization, organizational
unit, and person. An entry at each level has certain attributes, some of which are
optional. Any organization can implement a directory provided it adheres to the
structure. The X.500 standard does not cover the contents of the directory, so companies can maintain any type of information desired in the database, filtering
and screening to keep parts of it private. A company could, for example, publish
certain e-mail addresses, but keep everything else including telephone numbers
and mail stops private within the company.
Directory information is stored in a directory systems agent (DSA), which can
Represent one or a group of organizations. The interface to the DSA is known as a
directory user agent (DUA). DSAs communicate with each other using the Directory
Access Protocol (DAP) and the Directory Service Protocol (DSP). DSAs use DSP to
exchange directory information and DAP to retrieve information. Users not knowing
the e-mail address of another user can access the DUA much as they might call
directory assistance to get a telephone number. After they obtain the address, they
can store it in the e-mail application or in the central directory in an enterprise
e-mail system. DAP is too complex for most small intracompany mail systems.
These systems generally use LDAP, which is discussed later.
To be X.500 compliant compliant
, a system must provide four elements:
_ A DUA for user access
_ A directory service agent that speaks the DAP and DSP protocols
_ Basic directory functions such as information storage saving of computerized information, retrieval, and
updating
_ Security including user authentication


INTERNET MAIL
As e-mail becomes mission critical in many companies, the message volume the
Typical worker must contend with grows , and handling it becomes a problem.
Hackers and other miscreants regularly use e-mail to propagate viruses , worms,
and Trojan horses through firewalls security system for protecting against illegal entry to a local area network which is connected to the Internet (Computers) and on to their victims’ computers. (A Trojan
horse is a program that performs some detrimental action while pretending to do
something else. For example, fake login programs prompt users for logins and
passwords.) Unwanted e-mail, popularly known as “spam” permeates the network,
clogging servers and wasting bandwidth with transmissions that are useless
or worse. To cope with this growing problem, e-mail systems are becoming more
intelligent, classifying mail based on information in the header head-first dive; butt, ramming; top title, title which appears at the top of every page of a document, known noxious sites, key words, and other such methods of prioritizing and discarding throwing away, getting rid of some object that is considered useless or not worth having messages.
These techniques , called rules-based messaging, enable users and administrators
to filter

messages that might otherwise inundate them. Unfortunately, some benign
messages are filtered out in the process. Many e-mail systems temporarily quarantine
messages, leaving it up to the users to decide whether to discard

them.
Many application programs such as word processing and spreadsheets are
messaging system enabled. A mail-aware program knows that a messaging
system exists, and how to send data over it. It does not know how to process the
data. Amail-enabled application generates e-mail messages and uses the message transfer system to transfer information through the network. A mail-enabled
application can do everything that a mail-aware program can, plus it can route,
receive, and authenticate messages.
Simple Mail Transfer Protocol
Although comparative
statistics are not available, there is little question that the
quantity of messages sent on Internet e-mail far exceed those on X.400 networks,
even in European countries. SMTP is an easy and unsophisticated
mail system
that was first set up between UNIX computers. Figure 29-3 shows how UNIX
computers transfer mail between each other. To send a message, the sender types
the message into the UA, which passes the message to the MTA. Each computer
can reach a DNS, which contains the IP address for every user on the network. The
MTA transfers the message to the other computer via a TCP/IP link, locally over
Ethernet or to a distant network over the Internet. The two MTAs carry on a
simple dialog to establish communication. The message transfers to the receiving
MTA, which stores it in the user’s mailbox. If the addressee is unknown, the
receiving MTA returns a message to that effect.
By itself, SMTP can handle only seven-bit ASCII text, which means that
additional software is needed to enable a message to carry a binary file. The IETF
developed a protocol known as Multipurpose Internet Mail Extensions (MIME),
which converts files into a format that SMTP can handle. All mail servers that
enable users to attach files to messages implement MIME.
F I G U R E 29-3
Simple Mail Transfer Protocol
A major difference between SMTP and X.400 is in the language used. X.400
communicates using ASN.1, which is a formal language for describing messages
to be exchanged between network devices. It communicates in binary, in contrast to SMTP, which communicates in text form. For example, a communication between
an e-mail client and a POP3 server uses simple commands such as USER, PASS,
and LIST to log in and retrieve messages. With a little practice, anyone can look at
the details of SMTP message exchanges and see what is going on.
Lightweight Directory Access Protocol (LDAP) set of protocols which enable computers to access X 500 information directories
The X.500 protocol is too cumbersome for many organizations to use, but some
method of maintaining directories is required. Every organization has its internal
directory, often printed on paper, and usually obsolete

before it can be distributed.
On-line connected to the Internet directories subdivision of a disk in which files are stored are the preferred method because they can be updated daily
if necessary. An on-line directory is easy for people to use, but it needs structure
to be used in machine communications. Applications must be able to find someone
regardless of location to send an e-mail, instant message, or voice call. This usually
depends on multiple interacting directories. Most enterprises have multiple directories
to manage the various applications that define their employees’ telecommunications
resources. Even products from the same manufacturer
such as a PBX PBX (Private Branch Exchange)
telephone system that is owned by an organization
and its
voice mail have separate databases that must be separately updated. By the time a
new employee is equipped with logins, passwords, authentication and authorization for devices such as telephone, voice mail, e-mail, an ID badge, a user account on one
or more servers, a door access code, pager, cell phone, and a company credit card, the
number of accounts that must be established is overwhelming The answer, increasingly is LDAP. With a properly configured directory, an HR person could add a new
employee, update the directory subdivision of a disk in which files, and automatically populate other directories.
LDAP defines:
_ A protocol for accessing directory information
_ Amodel defining the format and character of the information
_ A namespace defining how information is referenced and organized
_ A model defining the operations one can perform such a search, add,
delete, etc.
_ Amodel of defining how data may be distributed and referenced LDAP is now in Version which supports non-ASCII American Standard Code for Information Interchange and non-English
characters for international operation. LDAP enables users to look up information
from an online directory or e-mail contact list by entering the name or other
request. From a single request, LDAP can search multiple directories and return
various ways that the same person or information could be located. LDAP also
plays a key role in directory-enabled networks (DEN), which is a multivendor
initiative to simplify the management of complex networks through directories. LDAP directories are arranged in a hierarchy starting with a global name
and working downward in more detail such as department, division employee
name, and so on. It can also link a person’s name to other information such as
preference for being located. The LDAP hierarchy starts with the distinguished
name (DN). The DN is divided into separate or sever into parts domain components (DC), organizational unit
(OU), and common name (CN), ending with an attribute type and value. Here is
an example of how an LDAP directory might appear DN McGraw-Hill Corporation
DC Book Division
OU Professional Trade
CN Mary Smith
Address: 1333 Burr Ridge Parkway Burr Ridge, IL 60527
Phone: 630-555-1234
Fax: 630-555-4321
e-mail: marysmith@mcgraw-hill.com
The directory could be further enlarged to include such information as cell
phone number, supervisor, emergency contact information, preferred method of
being contacted, normal work schedule, deviations from the schedule, etc. Some
information can be kept private, while opening the rest to public view. The directory
information resides on a local server, which can be configured to pass information
to other servers such as one at corporate headquarters. LDAP can search
multiple directories or use URLs for directory look up. Accessible information
might reside in a Web page, a catalog, a human resource directory, or other such
servers, and LDAP can check them all. LDAP can reside on some endpoints. SIP
telephones, for example, can have LDAP capability. SIP for Instant Messaging and
Presence Leveraging Extensions (SIMPLE), a protocol for notifying IM users of
status changes, can also be implemented from SIP devices. Calendar and scheduling
information can be kept in the directory or accessed from other applications
such as an electronic calendar. Companies can keep records on customer purchases
and buying habits and associate them with entries in their LDAP directory.
Every e-mail program has a personal address book, but the question is how
you reach someone whom you have never communicated with before. LDAP
servers index data in trees and you can use a variety of filters to select a person or
group you want. Users can set permissions to allow only certain people to access
the database and to keep some information private. Servers also have an authentication
service to identify the person requesting information from a directory.
Instant Messaging
IM, once the province of teenagers, friends, and family members, is finding a place
in the enterprise as products gain business features. IM is an IP-based application LDAP directories are arranged

in a hierarchy starting with a global name
and working downward in more detail such as department division, employee
name, and so on. It can also link a person’s name to other information such as
preference for being located. The LDAP hierarchy starts with the distinguished
name (DN). The DN is divided into separate or sever into parts domain components (DC), organizational unit
(OU), and common name (CN), ending with an attribute type and value. Here is
an example of how an LDAP directory might appear:
DN McGraw-Hill Corporation
DC Book Division
OU Professional Trade
CN Mary Smith
Address: 1333 Burr Ridge Parkway Burr Ridge, IL 60527
Phone: 630-555-1234
Fax: 630-555-4321
e-mail: marysmith@mcgraw-hill.com
The directory could be enlarged to include such information as cell
phone number, supervisor, emergency contact information, preferred method of
being contacted, normal work schedule, deviations from the schedule, etc. Some
information can be kept private, while opening the rest to public view. The directory
information resides on a local server, which can be configured to pass information
to other servers such as one at corporate headquarters. LDAP can search
multiple directories or use URLs for directory look up. Accessible

information
might reside in a Web page, a catalog, a human resource directory, or other such
servers, and LDAP can check them all. LDAP can reside on some endpoints. SIP
telephones, for example, can have LDAP capability. SIP for Instant Messaging and
Presence Leveraging Extensions (SIMPLE), a protocol for notifying IM users of
status changes, can also be implemented from SIP devices. Calendar and scheduling
information can be kept in the directory or accessed from other applications
such as an electronic calendar. Companies can keep records on customer purchases
and buying habits and associate, them with entries in their LDAP directory.
Every e-mail program has a personal address book, but the question is how
you reach someone whom you have never communicated with before. LDAP
servers index data in trees and you can use a variety of filters to select a person or
group you want. Users can set permissions to allow only certain people to access
the database and to keep some information private. Servers also have an authentication
service to identify the person requesting information from a directory.
Instant Messaging
IM, once the province of teenagers, friends, and family members, is finding a place
in the enterprise as products gain business features. IM is an IP-based application users’ presence can be indicated by status messages such as stating that they are
out of the office or on vacation. The directory provides a way for users to communicate
their reachability state of being reachable; attainability and communication profile as a means of controlling
how others communicate with them. Users can receive messages even while off
line/pending messages are delivered when they log in. Most messaging systems
have a presence -awareness feature. The basic level indicates whether the user is
online and willing to accept messages. Users can elaborate on the basic level with
additional status messages. This brings up a privacy issue since users must be
assured that their personal information is available only to trusted users. The fact
that a person is on vacation or out of town, for example, would be provided to
business colleagues and the family, but not to strangers.
Besides the ability to pop messages on other users’ screens, chat rooms are
the most valuable feature of IM products. With these, users can set up online meetings
either informal or with a moderator. Chat rooms can be restricted to a limited
group of users that are screened and approved, or they can be set up as public so
anyone can browse. Users can click a button to “raise their hand” to be recognized. Sessions can be browsed and searched and replayed in real time or users
can fast forward and rewind through the meeting. If it is a public meeting, all
users can see it, but the moderator can password protect the chat room.
In addition to chat rooms, enterprise IM products have a variety of features such
as the following that are among the most valuable:
_ News board: This feature lets users post announcements for general
consumption
_ Content filtering: Inappropriate language can be filtered out of chat
sessions and online news boards.
_ File and screen sharing: IM provides an easy way of sending spreadsheets
and other documents as file attachments.
_ Whiteboard and screen sharing: Participants in a meeting can all share a
whiteboard or information on other users’ screens.
_ Management and reporting tools: Tools show information such as who is
logged in, how many active meetings are in progress, and who is using
tools such as whiteboarding and videoconferencing.
_ Polling: IM can distribute polling screens requesting users to respond to
multiple-choice polls. For example, several alternatives could be
displayed for the company picnic and the system could collect and
summarize the results.
_ LDAP integration: The user directory can run under LDAP, which brings
numerous benefits over and above IM. Some products have proprietary
directories or run under a directory such as Netware/NDS.
_ Message encryption: Most products support encryption to keep confidential
messages out of unauthorized hands. _ IM platform integration: Some products can integrate with other IM
platforms or servers that may be applied by business partners or other
outside organizations. Some products can interface with public IM
networks.
_ Scheduling calendar: Some products provide an online scheduling calendar
that can be used to reserve chat rooms and show who is using the
space.
Unlike the IP protocol on which it runs, IM is proprietary. Products can be
designed for interoperability, but in most cases some features will not operate
between platforms. The IETF is working on Instant Messaging and Presence
Protocol (IMPP), which is an architecture for simple presence and awareness notification.
It specifies how authentication

, messaging integrity, encryption, and
access control are integrated. Message formats may also be proprietary. Extensible
Messaging and Presence Protocol (XMPP) is an XML-based protocol for near realtime
extensible messaging and presence that the IETF is working on to standardize
message formats.

ELECTRONIC DATA INTERCHANGE transmission of standard electronic documents between computer systems of companies or business organizations
Global markets are changing the way we do business. To remain businesses must know their customers and respond to their needs. In international
trade it takes an average of 46 documents to move products across boundaries.
Traditional mail is too slow, and facsimile is impracticall to authenticate
for some
applications, which raises the need for electronic document interchange. EDI is the
intercompany exchange of legally binding trade documents. EDI enables companies
to exchange a variety of business documents such as invoices, requests for
proposals, and shipping and purchase orders over an electronic network.
EDI offers both cost savings and strategic benefits to the trading partners.
Cost savings come from reduced labor costs, reduced stock levels that result from
shorter document turnaround, and savings in telephone and postage costs.
Improved response time is a major advantage,. Companies can respond quickly to
purchase orders, requests for quotes, and other such documents. In the past, trading
partners developed document formats they could use between themselves,
but it was impractical to make these arrangements with multiple trading partners.
An international standard set of forms was needed. EDI was conceived in the
1970s, but its acceptance has been slow. Part of the reason has been that expensive,
often mainframe-based software was required. Now EDI can be implemented on
PCs at a much lower cost than mainframe or minicomputer systems. PC-based
EDI can be integrated with e-mail and documents can be transferred across the
Internet by taking appropriate security precautions.
EDI software performs two main functions. It maps the fields on EDI documents
with fields in the application software, and translates the data to and from
the EDI documents. EDI applications receive and prepare documents on the screen, allowing the user to fill in the fields from the keyboard. Mapping data between
fields is one of the most difficult parts of implementing EDI. It may be possible to
use a translation program to remap the fields from one document to another. In
the worst case it may be necessary , to print out the EDI document and rekey the
information into the application, which defeats much of the purpose.
Documents can be transferred by a variety of methods. Many large organizations
Maintain
\ EDI sites where documents can be transferred to a secure site by
FTP/s or HTTP/s. EDI transmission of standard electronic documents between computer systemscan be implemented through store-and-forward messaging
over value-added networks or sent over the Internet as e-mail attachments Portable document format (PDF) files are a convenient way of locking the content
of file attachments to ensure that they cannot be altered. Value-added networks
also offer document validation, security functions, and special reports. VANs may
also convert protocols between the trading partners if they are incompatible.
EDI Standards
Four types of EDI standards are used:
_ Proprietary
_ Noncompliant and industry specific _ National, such as ANSI X.12
_ International, such as EDIFACT (EDI for Administration, Commerce,
and Transport)õóäàëäàà òýýâðèéí
EDIFACT is a complex set of EDI standards and rules developed under the
Auspices of the United Nations. Between ANSI X.12 and EDIFACT, standards have
been developed for most documents used in electronic commerce.
ELECTRONIC MESSAGING APPLICATION ISSUES
The Internet has revolutionized e-mail, evolving into a wide-open worldwide
backbone for fast and easy document delivery. It is also vulnerable as evidenced
by the attacks that have infected millions of computers with worms and viruses
and cost billions of dollars. Nevertheless, there is no turning back to the days
when creating and sending e-mail was hardly worth the effort
E-mail Evaluation
In selecting an e-mail system, the following are some issues that should be evaluated:
_ Adherence to standards: All e-mail systems support SMTP, MIME, POP-3,
and IMAP-4. Many systems also support LDAP. A messaging system may
need to connect to an X.400 system for some types of communication.
_ Ease of setup: E-mail server setup is not a trivial task with most systems. In
large organizations with thousands of users, some method of generating the accounts automatically should be provided Some systems provide
or ASCII files.
_ Security: Determine whether the system supports authentication and
Encryption conversion of data into cipher methods such as Secure Sockets Layer (SSL), which enables
Web clients and servers to pass confidential information securely by
encrypting it. The system should provide logs that the administrator can
view to detect such matters as repeated ineffective attempts to log in.
The system should provide an effective way of rejecting viruses and
filtering spam.
_ Choice of client: The using organization may standardize on client
software because it is part of a groupware application. The client and
the server may therefore be from different manufacturers. Determine
whether they support the necessary protocols to interoperate.
_ Disk management: Users are often careless about purging messages,
which may consume disk space rapidly, particularly when large files are
attached. The e-mail system should have tools for limiting message
storage space and for notifying users to purge old messages.
_ Additional applications: Many mail systems provide for other applications
besides mail receipt and delivery. For example, a corporate bulletin
board is one popular feature. Other common features of the client are
document control, calendar, and contact manager.
_ Usage information: Determine whether an audit trail through the system is
needed. Is message receipting necessary? Should the system provide usage
statistics for charging back to users or determining which departments
are the high users?
_ User interface: The user interface must be easy to use for composing,
sending, receiving, and managing messages. Users should be able to cut
and paste to and from word processors, attach files, easily, and move
them seamlessly across the network.
Instant Messaging Evaluation
Although IM is similar to e-mail, it has advantages that warrant its application in
many organizations. Although e-mail is supposed to be practically instantaneous,
sometimes it is not. IM is immediate and works in a conversational mode. It can
provide presence detection, and IM messages jump to the top of the priority list,
which can be a disadvantage. The following are considerations in selecting and
applying IM:
_ Security: Enterprise-grade systems should provide for end-to-end
encryption, authentication of participants, virus checking, and content
filtering. Products should be capable of rejecting unwanted IM messages. _ Peer-to-peer, public, or server based: Server-based IM is more appropriate
for larger organizations. Public IM raises security and privacy issues.
_ Interoperability: The proprietary nature of IM may become an impediment.
If trading partners use IM, compatibility of different systems may
become an issue. The system should be capable of implementing SIP
and SIMPLE as they are added to the network.
_ Directory integration: The IM system must be able to link to the corporate
directory, preferably on LDAP. It should be capable of detecting user
presence and communications preferences.
_ Auditing and logging: IM sessions should be logged and archived at the
server for later retrieval and playback. This is particularly critical in
organizations that are under a legal obligation to retain document
communications.
_ Feature implementation: The distinguishing factor among IM alternatives
may be the features the product provides. Such features as whiteboard,
voice and video conferencing, and sharing of computer applications
such as documents and spreadsheets are important in most enterprises.
EDI Evaluation
To implement EDI, a company needs four principal elements:
_ User application: This is the software that generates and receives EDI
documents. The major partner in an EDI exchange may furnish the
software. If not, review packages on the market, looking primarily for
ease of use. Programs that operate under a graphical user interface are
the easiest to use.
_ EDI software: This software translates the user application to EDI
message formats, provides the communications protocol for accessing
the network, and translates incoming EDI messages to the user application.
This software may be bundled with the user application software.
_ EDI hardware platform: This is a computer for running the EDI software.
In large companies it may be a mainframe or minicomputer. Most
companies starting EDI implementation will run it on a PC.
_ Network: If permissible, Internet is the easiest way to transfer messages.
If a VAN is used, either a dedicated or dial-up access is used.

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