Mary Ann Horton - UNIX and Internet Work

UNIX and Internet Work

In 1981, Horton became a Member of Technical Staff of Bell Labs in Columbus, Ohio. At Bell Labs she brought parts of Berkeley UNIX to UNIX System V, including vi and curses; as part of the work on curses, she developed terminfo as a replacement for termcap. In 1987 she joined the Bell Labs Computation Center to bring official support for Usenet and Email to Bell Labs.

Horton continued to lead Usenet until 1988. During this time she promoted rapid growth by arranging news feeds for new sites. Each new site agreed to be the feed for two more new sites as the need arose. This policy contributed to the growth of Usenet to over 5000 sites by 1987. Along with Rick Adams and Eugene Spafford, Horton created the Usenet Backbone, later described as the Backbone cabal. The backbone insured the reliability and performance of the overall network.

Usenet began with only a few messages per day, but volume rapidly grew to become a problem. Horton added moderated newsgroups, distinguished with names beginning with "mod" or containing "announce", and moderated the first such newsgroup: news.announce.important. Only the moderator could post messages, all other messages were automatically sent to the moderator for approval. Eventually the B News software was enhanced to permit any newsgroup with any name to be moderated.

Usenet relied on email for replies, requiring that Usenet links could be used for email. At first, all Usenet and UUCP messages used "bang paths", such as unc!research!ucbvax!mark, as email addresses. Horton guided this email process, including the use of the ARPANET/UUCP gateway, using routed email addresses such as cbosgd!mark@berkeley. These addresses were complex, convoluted, and sometimes ambiguous. When Internet domains were first created in 1983, Horton championed their use, publishing the classic paper "What is a domain?"

At Usenix in January 1984, Horton recruited a group of volunteers to create the UUCP Mapping Project. The project divided the world into geographic regions. A volunteer for each region maintained the region's UUCP connectivity map and posted it regularly to the comp.mail.maps newsgroup. Each site ran Steve Bellovin and Peter Honeyman's pathalias program to create a locally optimized email routing database from this map. Horton worked with Chris Seiwald and Larry Auton to produce the smail program, used this database to route email, using email addresses such as mark@cbosgd.UUCP.

In the mid 1980s, early domain use included .ARPA, .UUCP, .CSNET, and .BITNET as top level domains, representing four major email networks. In January 1986, Horton represented UUCP at a meeting to arrange technical cooperation of these networks. Others were Dan Oberst representing BITNET, Craig Partridge representing CSNET, and Ken Harrenstein, who hosted the meeting on behalf of the ARPANET. Harrenstein convinced the others to support the creation of six top level functionally domains COM, EDU, ORG, NET, GOV, and MIL. Each network was authorized to register domains in COM, EDU, ORG, and NET. This group of registrars was the precursor to the ICANN domain name registry.

Horton implemented the UUCP portion of the registry by reorganizing the UUCP Project into the "UUCP Zone". With Tim Thompson, Horton registered 150 UUCP-only organizations with officially sanctioned .COM and .EDU domains. mark@stargate.com became a valid UUCP email address, even though the message was delivered via UUCP using dial-up modems.

The UUCP Zone joined with Lauren Weinstein's Stargate project, which built a pilot project to transmit Usenet over satellite television, to form Stargate Information Systems. The first domain they registered was stargate.com, the second was Horton's employer, att.com. The att.com domain connected to the Internet using dial-up modems until 1990, when Horton implemented Bill Cheswick's firewall architecture to build AT&T's first TCP/IP connection to the Internet with a demonstrably secure firewall.

Horton's 1990 book, Portable C Software became a popular reference for programming in C. It outlined functions and programming techniques that could be reliably used on many different types of computer systems, and which methods were unportable.

In 1992, Horton created an internal email package for Bell Labs called EMS (Electronic Messaging System). This package integrated the existing UUCP-based email system with the AT&T "POST" white pages directory and the domain-based email world. She created and led a supported email service for Bell Labs. This system supported many email addressing formats, including those that dynamically queried the POST directory:

• Handle: mark@att.com
• Full name: Mark. R.Horton@att.com
• Broadcast to a building: loc=oh0012/all=yes@att.com
• Complex query: all technical managers and directors in Columbus: loc=oh0012/tl=tmgr/tl=dir/all=yes@att.com

In 2000, Horton joined Avaya, where she was the Sr. Manager of Avaya Corporate Email and Directory. In 2002, Horton joined the UNIX Implementation Engineering group at Bank One, which was purchased by JPMorgan Chase in 2004. Finally fulfilling a lifelong dream, Horton moved from Columbus to San Diego in 2007, joining Sempra Energy's Transmission Grid Operations team.