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Electronic Mail Systems A Network Manager's Guide

17/10/2014 Uploader: AMBN Loại file: pdf - Loại file: epub - Loại file: lit - Loại file: prc

All Electronic Mail (E-mail) systems are not created equal. Welcome to the won-der ful and incredibly diverse world of E-mail, where more than 100 distinct E-mail sys tems (operating on every imaginable computing platform) are just waiting to be discov-ered! Choosing the right E-mail system for their native environment is a critical dilemma faced by many companies.

Electronic Mail Systems A Network Manager's Guide



Burhan Fatah, Ph.D



 • TCP/IP Networking: A Guide to the IBM Environment NEMZOW

 • Enterprise Network Performance Optimiza-tion DAVIS

 • Wireless Local Area Networks: Technology, Issues, and Strategies HUTCHINSON

 • ISDN Computer Applications Development SlGNORE, STEGMAN

 • The ODBC Solution: Open Database Connectivity in Distributed Environments RICHARDSON

 • Writing VX-REXX Programs SCHATT

 • Linking LANs—2nd Edition BLACK

 • TCP/IP and Related Protocols—2nd Edition BLACK

 • Network Management Standards: OSI, SNMP, and CMOL Protocols—Second Edition


 1. E-mail Evaluation Task Force 33


 2. Upper Management Questionnaire 340


 3. Select a Few E-mail Systems


 4. Send Questionnaires to the Vendors 340


 5. E-mail Associated Costs 34


 6. E-mail Comparison Tables 1


 7. The E-mail Test Network 34


 8. E-mail System Testing 8 Testing Standard E-mail Features 34 Summary 350 Epilogue The Trends and Future of E-mail 351


 Appendix A Electronic Mail Systems 355


 Appendix B Acronyms 365 Glossary 367 Bibliography 370 Trademarks 371

Index 375

About the Author



 Acknowledgments xvii



 Chapter 1. Introduction to Electronic Mail and Operating Platforms

1 Intended Audience 2 How the Book Is Organized 2 Costs As-sociated with E-mail 3 E-mail as Technology 4 Important Characteristics of an E-mail Sys-tem 4 Store-and-Forward Transport Services Directory Services 5 Routing Services Trans-lation Services Standard Features Provided by an E-mail System 6 Advanced Features Pro-vided by an E-mail System 8 Emerging E-mail Ideas and Technologies 11 Client/Server Computing 1 Distributed Processing 2 Mail-enabled Applications Workflow Automation 13 Multimedia 1 EDI Integration 4 FAX Integration Voice Integration 15 Telex Integra-tion 6 Popular Operating Environments for E-mail 1 Personal Computer Environment 17 DOS 1 OS/2 8 Microsoft Windows 1Macintosh 9 UNIX Midrange Computer Environment 21 Mainframe Computer Environment LAN Envi-ronment 22 Ethernet 3 Token-Ring 4 ARCnet 5 FDDI 2 Network Operating Systems (NOS's) 2 AppleTalk Banyan VINES 26 LAN Manager LAN Server 7 LANtastic NetWare 2 PathWorks 8 POWERLan 9 UnixWare WEB 30 10 NET LAN Management 3 LAN-to-LAN Connectivity 1 WAN Environment 4 Frame Relay 35 ATM ISDN Dial-up Wireless 36 Summary


 Chapter 2. E-mail Standards and Protocols 37

OPEN Protocols 37 Open Sys-tems Interconnections (OSI) 38 NetWare Message Handling Service (NetWare MHS) 47 Simple Mail Transfer Protocol (SMTP) 55 Systems Network Architecture Distribution Ser-vices (SNADS) 59 Application Programming Interfaces (APIs) 60 Mail Application Pro-gramming Interface (MAPI) 61 Open Collaborative Environment (OCE) 6 Open Messag-ing Interface (OMI) Standard Message Format (SMF) 1 Softswitch Network Application Programming Interface (SNAPI) 61 Service Provider Interface (SPI) 62 Vendor Indepen-dent Messaging (VIM) X.400 Application Programmin Interface Association (XAPIA and APIA) 6Summary 6


 Chapter 3. LAN-based E-mail Systems 63

Air Mail 63 a la mail 5 Banyan Mail BeyondMail 67 Brainstorm 73 cc:Mail 4 Chameleon 82 CompletE-Mail Coordinator 5 DaVinci E-mail 86 Einstein E-Mail 90 ENTERPRISE MAIL 2 Executive 5 ExpressIT! 6 FirstClass 98 Higgins E-Mail 9 ISIS Notes 101 JetForm for E-Mail 103 LapMail 7 Lotus Notes 8 MagicMail m Mailbox 112 MailMAN 3 MailPlus 5 MailPro 116 Microsoft Mail 117 M-MAIL 121 MultiMail Notework 6 NvMail 127 Office Works 129 Oracle Mail 130 Off ice Vision/2 1 PC/Mail 3 Pegasus Mail 135 Professional Write PLUS 13 QuickMail 6 Re-moteWare Mail 140 SAM (System for Automated Messages) 145 SEAmail 149 SECUREx-change 150 SelectMAIL 1 Sharklmail 3 Snap MAIL 154 SuperTime 6 TEAMTIMAIL 160 tPOSTVMXmailVoxMail 5 Wang OPEN/oflice 167 WHILE YOU WERE OUT! 17Win-Mai 171 WinNET MailWordPerfect Office 17XPost 8 Other E-mail Systems 9 Summary


 Chapter 4. UNIX-based E-mail Systems 181 ACM Mail 182

Applix Mail 185 Aster'x Mail 7 Cymail 9 Mail-it 190 Netix Mail Handler 191 Portable Mail 4 Siren Mail 195 Uniplex Mail 6 UXMAIL 7 Vmail 198 Z-Mail 201 Other Important UNIX-based E-mail Systems 204 ELM E-Mail/Serv 20 FXmail ILink/Mail 4 MH 205 MostMail NCRMail NeXTMail 20 OSILink X.400 5 PMX/Starmall 20 Promail S-Mail 6 V/Mail 20 Summary


 Chapter 5. Midrange

 Computer-based E-mail Systems 207 E/ZMAIL+ 208 Gold-Mail 9 HP DeskManager 211 JustMail/400 3 MAILBOX2 4 MAIL CALL 215 MESSAGE/CEN-TRAL 217 Message Minder NetMail'400 219 NetMail/3000 220 One-Stop Mail 2 OfficeVi-sion/400 223 QMAIL 226 Rydex Mail System 7 TeamLinks 230 T/MAILXpress 4 Other Important Midrange Computer-based E-mail Systems 235 DEC AII-ln-1 and VMSmail 23CEOSummary


 Chapter 6. Mainframe-based

 E-mail Systems 237 Electro Mail 237 Emc2/TA0 238 EMS—The MetaMail System for CICS 242 Memo 244 OfficeVision/MVS 245 OfficeVi-sion/VM 7 PROFS 248 SmartMail 250 SYSM 2 Other Important Mainframe Computer-based E-mail Systems 253 CA-eMAIL TOSS 254 Con-nect Vmail Summary 25


 Chapter 7. Public E-mail Services and Bulletin Board Systems 255

The Internet 256 On-line Services 257 America On-Line Bix 258 Delphi CompuServe Mail 25 GEnie 261 IBM Mail Exchange 26 Prodigy 2 Commercial E-mail Carriers 26 AT&T Mail and EasyLink 3 MCI Mail 26 Dis-patch 4 Bulletin Boards 265 PacerForum 6 The Bread Board System (TBBS) 26 The Major BBS 268 WILDCAT! 271 The Well 2 Summary 3


 Chapter 8. E-mail Connectivity and Inter-operability 275

E-mail Switches, Backbones, Hubs, and Integrators 275 AlisaMail 276 Cen-tral 280 Electronic Message Interchange (EMI) 283 Messaging Solution 285 Enterprise Mail Exchange (EMX) 7 Intelligent Messagin 29InterOFFICE Message Exchang 29Isoplex LANmail Connection 294 MAILbus 29 MBLink 6 Messenger 400 29 Missive 300 NetSwitch 1 NetWare Global MHS 302 OPENServer 400 5 Pathway 307 PMDF 9 StarPRO Enterprise Messaging 312 WorldTalk 400 313 Other Important E-mail Integra-tors 317 IMX-700 Mail'Hub 318 072 Message Engine 31 Lightspeed NVS 9 E-mail Gate-ways 31 Names Directories 320 Proprietary Directories 32 Directory Services 1 X.500 Di-rectory 32 Directory Synchronization 322 E-mail Management and Monitoring Tools 32 Mail Monitor 323 MailCheck 4 Mail Traffic Monitor 325 Gateway Manager Summary 326


 Chapter 9. Choosing, Evaluating, and Testing E-mail Systems 327

 Network Construction 327 Enterprise Mail Network 328 E-mail Connectivity Issues Transition Plan 329 Future Plans Mail Administration 32 Local Administration 9 Remote Administration 330 Admin-istrative Tools Levels of Authority 33 Security Issues 1 Backup Procedures 33 Archiving 33Security Features 2 Levels of SecurityPrivacyEncryptionPassword 3 Training Require-mentsAdministrator TrainingUser Training Programmer Training 334 Auditing 33 Sender Address 33 Destination Address 4 Mes-sage Size 33 Date and Time 5 Documentation and Diagnostic Facilities 33 Vendor-Sup-plied Documentation 33 Additional Documentation from Third Parties 335 Log and Trace Facilities 336 Support Issues 33 Product Scalability 7 Additional Users and Name Directo-ries 33 Transports 33 E-mail Connectivity and Interoperability 338 The E-mail Evaluation Process 339 E-mail Evaluation Guidelines and Milestones 33



 I am greatly thankful to hundreds of Electronic Mail and other ven-dors who pro vided me with literature, software, hardware, and artwork. Without their full coop eration a project of this magnitude would not have been feasible.



 All Electronic Mail (E-mail) systems are not created equal. Welcome to the won-der ful and incredibly diverse world of E-mail, where more than 100 distinct E-mail sys tems (operating on every imaginable computing platform) are just waiting to be discov-ered! Choosing the right E-mail system for their native environment is a critical dilemma faced by many companies.

 The dilemma results from the very large num ber of E-mail sys-tems that are available. Large corporations spend tens of thousands of dollars on selecting the right kind of E-mail system for their communication envi ronments. Even then, their final decision may not be the best one. One of the rea sons for not arriving at the best se-lection is that many people are not fully aware of all the E-mail systems available; this knowledge obviously is essential to making the best selection.

 There were more than 50 million E-mail users worldwide in 1992 according to International Data Corporation (IDC) from Farmingham, Massachusetts; this is up from 33 million in 1990, a 50% increase in just two years. IDC also estimates that the number of installed E-mail boxes will climb to 250 million by 1997. In the US there are presently over 30 million E-mail users and this number, according to BIS Strategic Decision, is expected to climb up to 85 million by year 2000; this figure could be very close to the total work force in the US at that time! It is, therefore, very important to understand the concepts behind E-mail (which are very sim-ple), the availability of various E-mail packages (which are too numerous), and most impor tantly, differences among various E-mail systems.

 This book is not intended to be a tutorial on E-mail (there are other books on the market which do just that), but a very detailed ref-erence on E-mail packages that are currently available. E-mail connectivity and interoper-ability issues are discussed in great detail. The intent is to review various E-mail systems in somewhat greater technical detail than is usual, to give the reader a feel for what is involved in setting up a particular E-mail system.

 Because E-mail technology is changing very rapid-ly, it is impossible to include all up-to-date, relevant information in one publication. By the time this book is in your hands, some new mailing services are already available, others have added a few more features, and probably some hav alread ceased to exist.

 But I expect most of the existing E-mail packages discussed in the book to remain in the market and re tain all the mentioned features. I have made an attempt to lay out a framework for understanding the fundamen tal concepts behind E-mail and E-mail systems, and I have tried to provide enough information to equip readers to continue gathering and evaluating information so that they can reach the best selection for their native environments. Every effort has been made to include all the relevant information about specific E-mail pack ages.

 But, due to a very large number of software packages available from single companies and/or third parties, software that interoperates with specific E-mail packages, it is quite possible that I might have omitted some of these additional soft ware packages. This omission is absolutely unintentional.

 It is, therefore, necessary to contact E-mail vendors for ad-ditional information on particular software pack ages and information on the availability of other software of interest that might be available through them. It is not intended, de-sired, or expected that you would purchase an E-mail system based only on the informa-tion that I have provided in this book. This is only the first step toward your final selec-tion.


Chapter 1 Introduction to Electronic Mail and Operating Platforms

Electronic Mail (hereafter referred to as E-mail) is almost mystic to many people. It is considered quite complex to use because it requires direct contact with a key board attached to a terminal, which is further connected to a computer (or is the computer itself). Because not many people have regular contact with computers on a daily basis, it is presumed that using E-mail on a computer is not easy. But, in reality, the concepts behind E-mail are no more dif-ficult than receiving or sending a letter.

 Anyone who has ever been to a post office to mail a letter and can type on a computer terminal should be able to grasp the basic concepts be-hind E-mail fairly quickly. Let's discuss a letter-writing scenario in which you write or type a letter, enclose it in an envelope, put a destination address on the envelope, include your ad-dress in the top left corner of the envelope, and then debver it to the nearest post office.

 From there on, it is the job of the post office administrator and other services to deliver the letter to its final destination, be it local or in a foreign country. There are many ser vices involved in this transaction, such as letter sorting by the post office personnel and travel by trains, airplanes and so forth; but as the author of that letter, you are not involved in de-tails on how your letter may travel to its final destination. E-mail works in a very similar fashion.

 An E-mail system consists of a post office and mail boxes, just like a P.O. Box in the post office. You replace your pen and pa per with a keyboard and a computer screen. Type a letter on the computer screen, include the address of your destination, and then in-stead of going to the post office you just hand it over to the E-mail postmaster, who takes care of it from there all the way to its final stop.

 There may be several intermediate steps in-volved before it reaches its final destination, but as the sender of that E-mail message, you are not worried about how it gets there. However, it is a very different story if you are an E-mail administrator in a large organization and your main assignment is to ensure a smooth flow of E-mail round the clock. This may be the toughest and scariest job you ever had; or it may be the most challenging, enjoyable, and satisfying experience of your professional life. What makes the difference is whether you have mastered the major concepts re lated to E-mail. Intended Audience This is a reference book on E-mail in general and E-mail systems in particular. The following readers will benefit from this book:


 • The network administra-tor or manager who understands E-mail and related con cepts very well but would like to find out the best E-mail systems available today as well as the connectivity and interoper-ability issues among these systems.


 • An experienced E-mail user who uses E-mail to com-municate frequently but would like to further enhance his knowledge and become more in-formed about E- mail concepts and systems.


 • A novice user of E-mail who will learn the concepts and terminology used in every day E-mail life, and get acquainted with various E-mail systems on all computer platforms.


 How the Book Is Organized

This book is designed to be modular, as any reference book should be. The reader can skip around to find the desired information without losing continuity. Because this book is not intended to be a tu-torial on E-mail systems, it is assumed that the reader is familiar with basic concepts of computer operating systems, computer networks, and data communications systems.

 Chapter 1 is probably the most basic and genera] chapter in the whole book. In this chapter, I introduce users to the most fundamental E-mail concepts, terminol ogy, and technologies in use today. Later in the chapter, E-mail operating platforms are discussed that include all major computer systems and environments. This chapter is highly recommended for novice readers.

 Chapter 2 discusses all major E-mail standards and protocols that are inter-na tionally accepted. Also, all leading Application Programming Interfaces (APIs) are dis-cussed. This chapter is targeted at experienced computer professionals who would like to enhance their E-mail knowledge by learning more about the underly ing structure of E-mail protocol suites.

 Chapter 3 reviews over 50 LAN-based E-mail systems. Each review includes a brief introduction to the E-mail system and describes its main features. This is fol lowed by a discussion of connectivity issues and operating platform requirements for the system.

 All PC-based E-mail systems are classified under these categories, and Macin-tosh computers are, too.

 Chapter 4 reviews UNIX-based E-mail systems. Some of the sys-tems discussed here may also qualify under other categories of E-mail systems, but the UNIX oper ating platform is still their main strength. The review criteria are the same as de scribed for LAN-based E-mail systems in Chapter


 Chapter 5 reviews E-mail systems for midrange computers, such as DEC, Wang, AS/400, Hewlett-Packard, etc. Some E-mail systems that were discussed in Chapter 4 may also qualify for this catego-ry of computers. The review criteria are the same as described for LAN-based E-mail sys-tems in Chapter


Chapter 6 reviews mainframe-based E-mail systems. This category is dominated by E-mail systems that run on IBM mainframe operating platforms. The review cri teria are the same as described for LAN-based E-mail systems in Chapter


Chapter 7 reviews public E-mail carriers, E-mail OnLine service providers, and some major Bulletin Board Systems (BBS's). A review of the Internet and the ser vices it provides is also includ-ed. There are no review criteria set for this category of E-mail systems, because the level of E-mail services provided differs substantially among vendors. Among thousands available, only a few major bulletin board sys tems are discussed, so as to give the reader a sense of what they offer. This chapter is particularly important for individuals and small companies who like to communi cate externally via E-mail.


 Chapter 8 discusses interoperability among different E-mail systems. Once you have learned about over 100 E-mail systems, you may want to find out how these disparate E-mail systems talk to each other. This chapter is a must for any E-mail administrator or any company that deploys more than one E-mail sys-tem.


 Chapter 9 provides a detailed review on how to evaluate E-mail systems. This step-by-step approach describes how to select an E-mail system that is just right for you. This chapter is a must for anyone wishing to purchase an E-mail system.


 Appendix A lists more than 350 E-mail packages currently available. These E- mail systems are further classified accord-ing to their operating environments. This appendix is a must see for all readers of this book.


 Appendix B is a list of acronyms commonly found in the world of E-mail.


Costs Associated with E-mail

How much does it cost to install a new E-mail system? There is no definitive answer to this question, because cost varies substantially among different vendors. Besides, costs for E-mail systems change on regular basis, depending on competition, supply and demand, etc.

Therefore, I chose not to go into the cost factor when reviewing various E-mail systems in the subsequent chapters. Also, the operating platform and the number of users on the network are important factors that contribute to the costs associat-ed with an E-mail system. Generally, LAN-based E-mail systems are cheaper than main-frame or midrange computer systems.

 Also, one does not buy a public E-mail system or service, but rather subscribes to it for a monthly fee. A recent study by WorkGroup Tech-nologies shows that the average price of an E- mail system is about $58 per user, which is about 'A, of the cost in 1989. Again, this is a very rough cost estimate, and it should not be generalized to include every E-mail system. Some vendors, such as IBM, charge an addi-tional annual licensing fee on top of other costs. Also take into account after-purchase costs, such as support costs (which could be substantial, especially in the first year of the purchase). Perhaps the two biggest cost factors during the first year of a new E-mail system are user training and administration costs, which could be as much as 75% of the total cost.

 Similarly, the return on your E-mail investments is difficult to measure, because E-mail adds a lot of value and efficiency to the overall corporate infrastructure rather than generating revenues itself. Moreover, it is a long-term investment and should not be perceived in terms of short-term goals. Consult Chapter 9 for more in formation on this subject.

E-mail as Technology

E-mail is generally understood as “sending text messages from one computer to an other.” But that is a limited definition of a technology that has the potential of dra matically altering the way we do business every day. E-mail is evolving at an ever-faster pace. As a result, it has been redefined more than once, each time adding new functions in its applications. E-mail is not simply a software package that could function entirely on its own.

 It has to be part of a system that includes computers, networks, transports, gateways, mail switches, word processors, and many oth-er ap plications that must work together to be useful and beneficial to users of a particu lar computer environment. We can, then, redefine E-mail: E-mail is the technology that trans-ports electronic objects from a wide vari ety of applications, including messaging, across heterogeneous computers, ap plications, and mail systems with store-and-forward capabil-ities.

 Having put forth such a general and broad-based definition, we must understand the individual parts of this definition in light of the technology that is available to us. This def-inition is bound to change in the months and years ahead as the technology improves, but many of these features are expected to be integral part of E-mail sys tems in the foreseeable future. One trend that is clearly emerging is the prevalence of few well-defined E-mail pro-tocols over many proprietary protocols, which have until recently dominated the E-mail in-dustry.


 Important Characteristics of an E-mail

System E-mail is a technology that may be used to provide multiple services, such as elec tronic messaging and mail-enabled applica-tions. Until recently, electronic messaging and E-mail were synonymous, because messag-ing was the only application of E-mail. Electronic messaging services allow users to ex-change messages, complex docu ments, and other forms of information such as video, au-dio, and image files.

 Realizing the potential that E-mail possesses, several vendors have come up with many useful applications that use E-mail as their primary transport. E-mail is an asynchronous service to transport information between users and applications. Central to this transport service is the capability of storing and forwarding information.

Store-and-forward transport services

One thing that clearly distinguishes E-mail from other tech-nologies is its store-and- forward capabilities. What this simply means is that a mail mes-sage recipient does not have to be present in order to receive a mail message that was just sent to him. As a matter of fact, the recipient does not have to be logged into the receiving com puter system at all. The message can be stored temporarily at any point on its way from source to the final destination. In the event a recipient is not logged on, the message most likely will be held by the recipient's computing environment and de livered as soon as the recipient logs onto the system. It is a nonintrusive operation and gives a lot of leeway to the operator to act in many different ways on the recip ient's behalf. The store-and-for-ward mechanism is not a real-time operation itself, but it takes full advantage of the under-lying real-time nature of the transport system to move an object from one point to another along its path.

 Movement of an object from one point to another is a synchronous activity that the store-and-forward mechanism utilizes while providing asynchronous connectivity itself. Because the sender and the recipient are not required to be present during a mail transaction, the store-and- forward becomes a very useful and convenient means of com-munication.


 Directory services

Directory requirements have emerged as the number one is-sue on the list of many companies. After deploying multiple E-mail systems, and then con-necting them to provide companywide communication, the biggest problem is how to manage users and their addresses across multiple E-mail systems. In many companies, the em ployee turnover is quite large and this requires constant modifications in the names di-rectories.

 The problem is further compounded when many different directories are in-volved.

 The X.500 standards define a completely distributed directory service, but the ma-jority of E-mail vendors have yet to implement it. Interim measures are needed to solve this problem. Many leading E-mail connectivity vendors have come up with an interim so-lution, which is to provide directory synchronization facilities. Under this scheme, directo-ries from different E-mail systems are often synchronized to up date changes on both ends to match each other.


 Routing services

Routing services are provided by the mail routers, which allow for a mail flow among users. The mail infrastructure is designed to transport information easily to its des tination. Routing information is found in the directories and routing tables, which are defined to facilitate transmitting information to its destination without making the sender worry about the details. As the standards for linking mail sys-tems are narrowing down to X.400, SNADS, SMTP and MHS, so are the headaches associ-ated with mail routing among disparate mail systems. Mail routers are becoming an essen-tial part of most E-mail backbone systems today.


 Translation services

All mail systems have some translation capability embedded in their basic architec ture. Translation services can be rudimentary translation of protocols or the content of a message file. The translations can become complex when multiple E-mail sys tems from different vendors are involved in a networked environment.

 Because different E-mail systems generally use different word processors, a translation mechanism has to be installed at all ends. In networks where an E-mail hub or messaging switch is deployed, the intermediary translations can generally be done at the switch level. Many E-mail vendors provide optional translators either di rectly or via third parties on an as-required basis.

Standard Features Provided by an E-mail System

All E-mail systems of-fer basic messaging functions such as sending and receiving simple notes. Most of them al-low you to reply to your received mail, forward it to somewhere else, save it in a file, or delete it. Beyond these basic services, the E-mail market starts restricting with what you can accomplish through your mail system. Not long ago mainframe and midrange computers offered the most advanced E-mail systems. But during the past few years, LAN E-mail sys-tems have come a long way.

 Now most of the advanced E-mail capabilities are to be found on the PC-based E- mail systems. Following is a brief list of what I call standard E-mail features. These are not the most advanced functions, but you still may not find all of them in a sin gle E-mail package. I expect many newer E-mail systems to incorporate the major ity of the following features, which are self-explanatory: ...Download this book here

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