Name: A history of engineering and science in the Bell System
ISBN: 9780932764065

What Hacker News says

nullcMar 2025

Article's point is though that they shoveled useful and relevant problems at them. This is extremely clear if you spend some time reading the BSTJ or the phenomenal "The History Of Engineering and Science in the Bell System" books.

So while there were not significant pressures to produce products there was a culture of working on relevant problems or in areas connected to relevant problems. ... rather than going full open-loop gazing deep into the category theory of their navels -- which appears to be an occasional failure mode of academia.

In working with academics in niche areas there often is a thirst for applications-- like you've found some interesting idea but where to go next? What constraints need to be solved for to make this interesting property into something useful. Applications would be a good guide if anyone would provide some, but the connections often don't exist. Part of the magic sauce of Bell labs must have been this enormous science and engineering driven industrial corporation that could just flood real problems at people who needed them.

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AnimatsSep 2023

If you're really into telephony history, the Internet Archive has "The History Of Engineering and Science in the Bell System" (3 volumes) online.

If you have to build reliable distributed systems, it's worth understanding how this was done in the electromechanical era of telephony, where the component reliability was much worse than the system reliability. "Number 5 Crossbar"[1] is worth reading, but hard to follow if you have no idea how telephone switching worked and are unfamiliar with the terminology.

Number 5 Crossbar, in current terms, was a collection of microservices. There was a big, dumb switch fabric, and "markers" which told it what to connect. Other microservices included trunks, originating registers (which listen to incoming dial digits), senders (which sent dial digits to the next switch), billing punches (which recorded toll call data for later billing), translators (which held routing tables), and trouble recorders (which logged errors.) Central offices had at least two of each resource, for redundancy. Resources were "seized" as needed from resource pools, with a hardware timeout and alarms to prevent resource lockup. If something went wrong in setting up a call, it was retried once, using different resources. If it failed on the second try, the caller got a fast busy and there was an alarm and a trouble recorder dropped a trouble card. Markers did not have persistent state. They started each call with a reset. So they could not get stuck in a bad state.

In the entire history of the Bell System, no electromechanical switching office was ever down for more than 30 minutes for any reason other than a natural disaster or a fire. It's worth understanding how they did that.

[1] https://telephoneworld.org/mdocs-posts/number-5-crossbar-sys...

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jcrawfordorJul 2023

None of these efforts are as wide-ranging as AT&T's, though. Budget comparisons are hard for a number of reasons (AT&T had R&D happening in multiple places, under multiple funding streams, both directly and indirectly funded), but the usual thinking is that AT&T spent a larger % of revenue on research than most, but not all, organizations today, with Google being a notable example of a company that beats it on % revenue to R&D (is this still true?). My suspicion would be that that comparison wouldn't hold if you factored in the directly funded DoD work but it's hard to say without some pretty complex digging through accounting records.

The more substantial point is breadth, though. AT&T research at its peak was more comparable to a university than an industrial R&D institution, with both basic and applied research occurring in a huge variety of fields---likely all fields of physical science at various points. All of the organizations you mention are essentially single-purpose. Some of the major tech companies (Google, Microsoft) are known for wide-ranging R&D, but they seem to have struggled to produce the kind of basic advances that AT&T did, and also seem to be backing off of that work.

Basic research is the big problem... AT&T had very little problem with money going to basic research without known applications, likely due to the substantial influence that academia and "scientific management" had on AT&T, as well as its reputation for excellent research management practices that made AT&T a major part of basic physics research on the behalf of the DoD for decades (Sandia National Laboratories, for example, operated by AT&T until relatively recently). In my opinion, accounts of Bell Labs enormous success, having made major contributions to nearly every field of engineering, often focus too much on the excellence of its staff (which was a factor, although Bell Labs management practices were not exactly modern), and downplay the role of AT&T's willingness to fund basic research and ability to find outside funding for basic research as well. Few modern organizations seem to be willing to entertain major efforts in a nascent field of astronomy, for example, on the assumption that the technical work will lead to useful engineering knowledge.

There's a lot out there about the history of Bell Labs, but its own multi-volume "A History of Engineering and Science in the Bell System," from the late '70s, does a good job of covering the incredible breadth and scale of work performed at Bell Labs. One thing to consider is that costs were quite a bit lower back then, and so Bell Labs small-looking budget of $3-5 billion of today's dollars per year translated to a workforce in the tens of thousands working, during WWII, 70-hour weeks. A two-day weekend did finally reach most of the Bell Labs technical staff early in the Cold War.

Besides, if you read into the history of Bell Labs, you will recognize vestiges of its bureaucratic structure in most government and military R&D today. Its influence in government and military physical research is enormous.

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AlohaSep 2019

The History Of Engineering and Science in the Bell System - The Early Years (1875-1925)

The History Of Engineering and Science in the Bell System - National Service in War and Peace (1925-1975)

The History Of Engineering and Science in the Bell System - Switching Technology (1925-1975)

The History Of Engineering and Science in the Bell System - Physical Sciences (1925-1980)

The History Of Engineering and Science in the Bell System - Communications Sciences (1925-1980)

The History Of Engineering and Science in the Bell System - Electronics Technology (1925-1975)

The History Of Engineering and Science in the Bell System - Transmission Technology (1925-1980)

There are two editions of Engineering and Operations in the Bell System one from 1983 and one from 1977.

Another one worth looking at is Transmission Systems for Communications.

For more information about divestiture, read Heritage and Destiny - https://www.amazon.com/Heritage-Destiny-Reflections-System-T...

At least some of these are available as PDF's from archive.org

Another thing looking at is back BSTJ articles: https://www.telephonecollectors.info/index.php/browse/bstj-a...

AT&T was anti-competitive, but it also spent much money on the public good, its a mixed bag - we did lose something with divestiture.

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AnimatsDec 2018

"A History of Engineering & Science in the Bell System: Communications Sciences, 1925-1980".

Here's probably the simplest introduction.[1] When reading this, note phrases like "ORIGINATING REGISTER SEIZES AN IDLE MARKER". Think of that as "originating register asks for an idle marker from the pool of markers". Very little equipment is dedicated to specific lines. Everything is done by requesting a service from one of several identical units. If one of those units fails, the system capacity is reduced, but the switch does not go down as long as at least one of each unit type is still up.

The switch fabric, the actual crossbars, is dumb. It just makes the connections it's told to make.

Shared resources include:

- Originating registers. These provide dial tone and record dialed digits. They parse the incoming number to the limited extent needed to decide when it's finished.

- Markers. The smart part of the system. When an originating register has a full set of digits, it finds an idle marker and sends it the call info. The marker figures out what to do next, in about half a second, and then it's free for another call. Markers tell the switch fabric what connections to make. They're duplicated, and the two halves check each other. If the halves disagree, the marking aborts. If a marker aborts, the originating register tries again with another marker. One retry only. Marker failures also cause data to be sent to a "trouble recorder". As usual, there's more than one of those, and they're "seized" as needed.

- Senders. These send digits from one exchange to the next. They're primitive modems.

- Trunks. Lines between exchanges. Full duplex, four wires.

- Terminating senders. The receive side of senders.

There are also units associated with accounting, coin telephones, routing tables, and other auxiliary functions.

The key takeway here is that there's no single point of failure.

[1] http://wedophones.com/TheBellSystem/pdf/no5crossbar.pdf

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nullcDec 2014

I had a delightful time reading "A History of Engineering and Science in the Bell System".

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