Plan 9, AT&T Corp Bell Laboratories’ successor to Unix, is making the move beyond its early success in academia towards the commercial market. And as expected (CI Nos 2,529, 2,367) it will appear first embedded in interactive consumer and telephone applications, rather than on general purpose computer systems. At the Consumer Electronics Show in Las Vegas a few weeks ago, AT&T Corp demonstrated two set-top boxes in a new family of TV Information Center products that use Plan 9 running on an Am29200 RISC microprocessor. The boxes also include AT&T’s 160X signal processor chip, audio RAM and video chip. The idea is to enable consumers to display information on their television screens downloaded from ordinary telephone lines and selected using on-screen menus. Local services bureaux are currently being set up by AT&T to filter information and handle customer billing. Services are expected to include home banking facilities as well as access to news and entertainment. The boxes, developed under the code name Sage, will be launched some time in the second quarter, according to Electronic Engineering Times. Zenith Electronics Corp will also use the functionality in its own televisions and set-top boxes due for launch in 1996. AT&T has already used set-top boxes running Plan 9 as part of Viacom Inc’s interactive television trial in Castro Valley, California. Sony Corp has developed a comparable system, called Apertos, in its Japan-based research labs, the paper pointed out. Meanwhile, Plan 9, developed in the main by Unix pioneers Ken Thompson, Rob Pike, Dave Presotto and Phil Winterbottom, with Dennis Ritchie as main cheerleader, has been gaining popularity among its academic users. Its macro-kernel base takes up just 170Kb and is enabled for fully distributed operation across an assemblage of bit-mapped terminals, processor servers and file servers. Components of Plan 9 include the alef concurrent object-oriented language; the 9P state-full simple network file protocol, rather than state-less as in Network File System; a 300Mbps network called Planet developed by Phil Winterbottom; and an audio compression algorithm capable of 13:1 compression, compared with the Moving Picture Expert Group’s 4:1. The current Plan 9 research project, Brazil, is said to look like Plan 9 on the outside but has numerous internal changes, including shortened kernel data paths to improve throughput. The windowing system was apparently re-written in four days by Rob Pike using the alef language. For those non-academics unable to get hold of Plan 9, there are a few Unix tools that make Unix look somewhat like Plan 9, including the 9term terminal emulator for X and gwm from Australia, which makes X look like a Plan 9 ‘blit’ terminal.
