While working on a software package to move Odd Lot orders/reports between brokers and the Odd Lot dealer, we were doing our usual Q/A, including [what we thought were] every possible bad input from brokers and Odd Lot dealer.
Aside from the usual OS-MVT consoles, the system was controlled by operators manning 83B3 teletypes. One of these operators said she could crash the system any time. When challenged, she planted her elbow firmly on the keyboard of an 83B3, sending utter garbage into the system. She did indeed crash the system and we realized that garbage input could come from unexpected places.
From 1981-1988, I ran the the Market Data II system at NYSE.
I converted it from a IBM /360-50 with 2703 Frontend (modified hardware) to IBM 4341 with 3705 Frontend (unmodified hardware).
Software in mainframe and Frontend was modified from IBM software.
From about 1974 until the late 1980s, I was responsible for maintaining Market Data System II, the mainframe system which gathered and reported trades on the New York Stock Exchange. This system was based on OS MVT Release 11 and was heavily customized/modified by IBM, with the promise to support it forever. In addition to a modified OS, IBM coded components to handle non-standard hardware and memory, as well as the infrastucture to support ‘applications’ modules.
In 1987, the NYSE had several computer systems in operation. The oldest and most critical one was the Market Data System known as MDS-II. This system gathered trading information from the Trading Floor and drove the traditional ticker tape as well as distributing the trade data over higher speed synchronous lines. Of the various systems, MDS-II was the only one which was absolutely critical to trading. While failure of the other systems was an inconvenience, failure of MDS-II halted trading completely, resulting in a lot of lost revenue for NYSE and its member firms.
In the mid 1980s, a manager told me we needed a system to monitor NYSE trades for violation of trading rules. He gave me two weeks to investigate possible methods and come up with a estimate of what needed to be done and how best to do it.
A note I wrote to Thierry Falissard’s OS site back in 2000, with some corrections by others.
Isn’t the Wayback Machine wonderful? 🙂
Those who employ professionals should respect the professionalism of their employees. The reason they hire specialists in the first place is because they themselves lack the requisite knowledge.
Management should never forget this. (Management is overhead, but that’s a tale for another day) 🙂
Working for IBM on Unit Record systems (Punched Card equipment) was my introduction to Data Processing, and to this day I think it was one of the most fun jobs I’ve ever done. Here’s one little tale of those days: