Cc:Mail
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[edit] Overview
cc:Mail is an obsolete, store and forward LAN based e-mail system originally developed on the Microsoft DOS platform by Hubert Lipinski in the 1980s. At the height of its popularity cc:Mail had about 21 million users.[1].
[edit] Message Store
The cc:Mail message store is based on a related set of files including a message store file, a directory and index file, and user files. In this structure, multiple users may have a reference in their individual files to the same message, thus the product offered a single instance message store. Message references in user files relate to message offsets stored in an indexed structure. Message offsets refer to locations within the message store file which is common to all users within a given database or "post office".
[edit] Client Technology
The cc:Mail system provided native e-mail clients for DOS, Windows, OS/2, Macintosh, and UNIX (the MIT X Window system under HP-UX and Solaris). cc:Mail allowed client access via native clients, web browsers, POP3 and IMAP4. cc:Mail provided the first commercial web based e-mail product in 1995.
[edit] MTA (Router)
The cc:Mail MTA or Router, which ran on DOS, 16-bit Windows, Windows NT, and OS/2, supported file access, asynchronous communications, and various network protocols including Novell SPX and TCP/IP. The cc:Mail Router also provided remote access to end users via dial-up and network protocols such as TCP/IP. The "remote call through" feature of the cc:Mail Router made it possible for a mobile user to connect through a single point to access any cc:Mail database within a given cc:Mail system. Various connection types and schedules could be configured along with conditions related to message attributes such as priority or message size to create complex message routing topologies.
[edit] Gateways
The cc:Mail system offered a wide range of e-mail gateways, connectors, and add-on products including links to SMTP, IBM PROFS, pager networks, fax, commercial e-mail services such as MCI and more.
[edit] Directory Services
cc:Mail provided directory synchronization throughout a system via an Automatic Directory Exchange (ADE) feature which supported a number of 'propagation types', such as peer, superior, and subordinate, from which sophisticated topologies could be constructed. cc:Mail also provided an e-mail based newsgroup or discussion like feature referred to a Bulletin Boards which were propagated and synchronized using similar mechanisms. Related features included the ability to synchronize the cc:Mail directory with other directories, such as that of Novell NetWare.
[edit] Server Technology
The core cc:Mail technology relied on OSI model network operating systems such as Novell NetWare. These network operating systems provided redirection of native operating system file I/O allowing network nodes to access server based files transparently, as well as concurrently.
Delivery of messages in cc:Mail is time invariant meaning that many database changes, such as message deliveries and deletions, can be under way at the same time without conflicting. Fundamentally, time invariance is made possible in OSI model network operating systems by the combination of the ability to write data to a file system past the end of a file and the ability to lock a record within a file.
[edit] Advantages
The shared file access architecture of cc:Mail offered significant performance benefits and made it possible for cc:Mail to implement a single instance message store years in advance of other products. The file-based nature of the message store also made the system very flexible and in some respects, e.g., moving a database to a new server, easy to manage.
[edit] Criticisms
The architectural approach of cc:Mail had drawbacks both in terms of scalability and in terms of vulnerability of cc:Mail databases to data corruption due to network errors or network operating system software defects. The cc:Mail system became notorious for its tendency to suffer database corruptions. Additionally, the technology was originally developed in a 1980s environment comprising disconnected LANs linked by dial-up connections. While the technology adapted well to WAN environments due to the robust nature of the Router, the system was best suited to a highly distributed deployment model. Client access over a WAN was not recommended because of poor performance related to the network traffic overhead of file I/O redirection and because of increased risk of database corruption. Although automation was possible, maintenance of large numbers of databases, each with relatively few users, was undesirable compared to highly centralized client/server systems where client access could be reliably provided over a WAN.
[edit] Client/Server cc:Mail
cc:Mail developed a native cc:Mail server, cc:Guardian, which would allow superior scalability, reliable client access over a WAN, and virtually eliminate database corruptions by removing file I/O access to the database. At the same time the development of POP3 and IMAP4 servers provided integration with Internet standards based client/server technologies. With the development of cc:Guardian and with support for POP3 and IMAP4, cc:Mail evolves into a true client/server platform. However, customers never deployed cc:Mail as a client/sever solution in large numbers.
[edit] Acquisition by Lotus
Lotus Development acquired cc:Mail, Inc., which was a Silicon Valley startup, in 1992 and used the cc:Mail technology to enhance Lotus Notes. Lotus Notes features derived from cc:Mail included Shared Mail, client type-ahead addressing, enhancements to the Notes MTA (also called Router), and the Notes Passthru feature.
Lotus, which was acquired by IBM in 1996, attempted to move cc:Mail customers to Lotus Notes, which was a superior client/server platform, but their efforts met with limited success, because of early challenges in the area of coexistence and migration between cc:Mail and Notes and because Lotus was focused on groupware rather than simple e-mail. Microsoft, which provided a simpler migration path and a more focused solution (e-mail), succeeded in winning the majority of the cc:Mail installed base in the Unites States. As a result, Microsoft today dominates the US market for enterprise e-mail solutions.
[edit] End of Life
LAN based e-mail technology was rendered obsolete by client/server e-mail systems such as Lotus Notes and Microsoft Exchange. The final version of cc:Mail, cc:Mail 8.5 was released in 2000.
- October 31, 2000: cc:Mail withdrawn from the market.
- January 31, 2001: All cc:Mail development ceased.
- October 31, 2001: cc:Mail telephone support ceased.
Despite its having been discontinued, a small number of customers continue to use cc:Mail and the product continues to be commercially supported by Global System Services Corporation [1].
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