How I got into Linux and UNIX



Having dabbled with Fortran and Pascal on Harris H100 and H500 mini-computers, and with Z80 assembler in the CP/M micro teaching lab I managed at Chelsea College, I got my first UNIX user account in 1985 courtesy of a friend - a dial-up account via a 1200 baud modem to an AT&T Bleasdale 3B2 mini-computer in an office off the Brompton Road. Frankly, I wasn't terribly impressed at the time, probably because I couldn't do anything useful with it and UNIX commands seemed so arcane then. I mean, with CP/M and MS-DOS computers you could write letters - theses even - and print them out, program hydraulic robots, do lots of fun things with BBCBASIC (86), get your household finances and telephone numbers organised with dBase2, etc. But an invisible computer far away on the end of a phone line? It just wasn't the same as having a real computer whirring away on your desk.

It was to be another 7 years before I encountered Linux - at the time MS-DOS 5 and Windows 3.1 were all the rage in the desktop PC world but that largely passed me by; in the early Nineties I was holed up in an electronics lab surrounded by logic analysers & oscilloscopes doing a lot of Z80, 8086 and 68000 assembler programming for the various lab computer interface cards I was developing for Queen Elizabeth's College, including the PC ISA bus, S-100 and G96 industrial buses. Windows (and MS-DOS) was far too slow for any real-time laboratory computing so I stayed with assembler. Great fun!

But for light relief, I was having even more fun with a network operating system called KA9Q NOS, which added TCP/IP networking features and more to MS-DOS with a rather UNIX-like command interface, and this led to me setting up King's College's first FTP server on the Kensington campus using KA9Q NOS on a 386 PC. At that time, all desktop computers there were stand-alone, there was no network anywhere in the college (only ASCII terminals connected by 9600 baud serial lines via Camtec PADs to the local VAX) and only half a dozen privileged users in the central computer centre had access to JANET's experimental implementation of the Internet over X25 serial terminal lines. Known as 'pandemonium' and accessible only through a dial-up modem in my office in the early days, this strictly unofficial FTP server supported ordinary serial file transfers using Kermit as well as SLIP (Serial Line Internet Protocol) and contained early MS-DOS and Windows Internet software. It became very popular - using Xmodem or Lancaster University's Kermit, users could download dial-up SLIP/PPP internet software and install it on their PCs in college or at home to make them Internet capable (it wasn't until Windows 95 was released with its built-in support for dial-up networking that the Internet became the mass-market phenomenon it is now).

Eventually the-powers-that-be at the main Strand campus sat up and took notice and it wasn't long after that I was offered the job of first setting up the college's first dial-up Internet service and then rolling out Ethernet networking everywhere and getting the entire college on-line. This lead to a seismic shift in my life; my career in electronics design and low level programming ended abruptly at that point as I jumped into the brave new world of computer networking. But that's another story.

I became an early user of Demon's fledgling 'Ten pounds a month' dial-up Internet service for email, ftp and gopher services - most early subscribers were either KA9Q users or real UNIX types since DOS, Windows and Macs at that time did not have any networking facilities. UNIX was beginning to look very attractive now but it was horrendously expensive. But it was through a CIX bulletin board one day that I first heard of Linux and thought: this is too good to be true - it's got to be better than DOS + KA9Q NOS and the idea of having a UNIX-like computer on my desk or at home for the price of a box of floppies was a no-brainer. And so I ended up installing Slackware 1.0 on a spare PC; I have not looked back since.

Meanwhile King's dial-up Internet service was a great success, with 18 phone lines feeding into a US Robotics Total Control rackmount modem bank supporting all modem speeds up to 64 kbit/s, and a Xyplex terminal server to handle SLIP (and later, PPP) connections. It was soon decided to offer secure access facilities for VIP users (eg, the principal, senior admin staff, etc) who already had the luxury of dial-back accounts, where after dialling in and identifying themselves, the connection would drop and they'd be dialled back one minute later at their home phone number. The SecureID system was chosen for this and this had to be hosted on a Solaris platform - a Sun SparcStation 4 was duly purchased and so I moved onto Solaris 2.3.

Funnily enough, the hostname pandemonium.cc.kcl.ac.uk is still registered in DNS!



Andy Thomas

Research Computing Manager,
Department of Mathematics

last updated: 27.10.17