113 This chapter presents a case study of the network-based service email, from its early days within the research community in the 70s through its stunning success in the late 90s, when the number of mailboxes grew to hundreds of millions in the United States alone. Initially, as many vendors competed for the dominant design, much experimentation occurred.
Because market uncertainty was high at that time, this experimentation was of great value. When Internet email won and the standards stabilized, the popularity of more centralized email services such as Hotmail grew.
Roughly 40 million more mailboxes currently exist for centralized email services than the more distributed (and traditional) ISP-based email sys- tems. This case illustrates the relationship between market uncertainty and management structure — when market uncertainty was at its highest in the 80s, the value of experimentation caused the distributed management structure to work best. Later, as the maturity of the technology caused mar- ket uncertainty to decrease, the value of the centralized management struc- ture overcame the advantage of end-2-end architecture. The emergence of a dominant design and stable standards indicates this reduction in market uncertainty. The history of email as presented in this case fits the theories of this book well.
The theory presented in Part One predicts the evolutionary pattern of email in the context of the standards that became accepted [1][2] and the
way the implementation of these standards unfolded in light of market uncertainty. At first, market uncertainty was high; many competing email architectures existed with both centralized and distributed management structures. Each vendor offered a different feature set, allowing customers many choices among different email services. As this theory predicts, when market uncertainty was high, distributed architecture was more popular;
as market uncertainty decreased, users migrated to a more centralized management structure. As this theory also predicts, the ultimate winner of the game (IETF Internet email) allows both distributed and centralized implementations of the standards, thus enabling it to prosper in any envi- ronment. Internet email is the architecture that allows the most experimen- tation due to its end-2-end nature, the openness of IETF specifications, and the modularity of those specifications.
History
There have been several different generations of email, as depicted in Table 8.1, with each generation influencing the services and architecture of the next generation. The rows of this table are the attributes of the email sys- tems that existed in the particular generation. In the research generation, academics experimented with email service. Then, in the geek generation, email became popular with technical professionals exchanging messages.
Next, in the business generation, the business community discovered that email could speed the flow of information and cut transaction costs.
Finally, email became a way for the average person to communicate in the masses generation.
Table 8.1 High-Level Email History
RESEARCH GEEKS BUSINESS MASSES
GENERATION (70S) (80S) (90) (95)
Systems IETF, OSI IETF, OSI, AT&T, MCI, IETF Post Office IETF, OSI,
(many other proprietary proprietary systems systems)
Management Distributed Distributed, Centralized, Distributed and centralized distributed centralized
Market Very high High Medium Lower
Uncertainty 114 Chapter 8
In the early 1970s computers were expensive and networks few; how- ever, email existed within the Internet for a select group of researchers. The 80s brought changes as computers became less expensive and more com- mon in the workplace, with telecommunications and networking technol- ogy coming of age, creating both the need and the ability to build email systems. By the late 80s, vendors and service providers were experiment- ing with many different ways to provide email systems. Even the U.S. Post Office saw the potential and planned to offer email service, but the FCC did not allow it [3]. Both open (X.400, IETF) and proprietary (AT&T, MCI, IBM) solutions existed, giving users many choices. As the 90s arrived, it seemed (at least to the pundits) that sanity had come to the world; the ISO X.400, based on open standards, allowed users on heterogeneous networks and computer systems to communicate. It was an open standard, allowing vendors and service providers to implement it. It did have competition from the Internet, but few believed the Internet (also an open standard, but with a very different standardization process [2]) to be a credible threat because of the overwhelming acceptance of X.400. This acceptance by ven- dors, users, and governments, though, did not translate into products that customers wanted. By the middle of the 1990s it became clear that X.400 had lost to Internet email, which emerged as the dominant design. Internet email was victorious for many reasons, as discussed in [2], including the initial greater complexity of X.400. Compared to a very simple initial Inter- net email standard, the better standardization of the IETF compared to the ISO (at least in my opinion), and the success of Unix along with the avail- ability of open source Unix-based email implementations. At about the same time, the MIME standard, which was created by the IETF in 1992 for encoding arbitrary (binary) content within email, came into widespread acceptance. The dream of interoperability and useful content exchange between users became reality: The dominate design was clear, and stan- dards stabilized to indicate low market uncertainty. Web-based email started its explosive growth at this point. It permitted efficient centralized management and could interoperate with any other Internet email server — the best of both worlds. By the end of 1999, these centralized email services were meeting the needs of the greatest number of users, as shown by the fact that they had the most mailboxes [4]. The following timeline is a summary of this history.
1973 Start of Internet email with RFC561.
1981 Simple Mail Transport Protocol RFC788.
Office Protocol for mail server client in RFC918.
Email Case Study 115
1984 Post Office Protocol (RFC918) for email client. Market totally unpredictable (size and structure). AT&T, ITT, GTE, MCI, RCA, WUI, Tymshare, GEISCO, IBM, IETS, ISO offer email. All systems are incompatible.
1990 Until now most mail intercompany; with arrival of X.400, long-term vision becomes clear.
1991 Move to X.400 a welcome sign.
Most email vendors adopted X.400 1992 Widespread conformance to X.400.
1993 Internet hits business radar; services like AT&T, MCI, and OSI-based implementations have slow (or no) growth;
Internet is growing fast.
1994 Gardner Group predicts SMTP should not be used for business because the lack of delivery receipts does not provide reliability.
1995 Win95 supports Internet email.
1996 Web browsers support SMTP/POP; Web-based email starts.
Standards-based systems cheaper, uncertainty lower;
MIME finished in November.
1997 SMTP/MIME is the only viable option for email.
1999 SMTP is the only choice; everybody is Internet-enabled.
Few are running Sendmail on their desktop.