A Hot Christmas?

25 Dec

In the UK, a “White Christmas” is somehow seen as the ideal Christmas. But that was never an option in the 20+ years I lived in Australia. So what was a hot Christmas like for a Pommy Bastard far from home?

In fact, after a few years, I really grew to like the Christmas in South Australia. It was always warm, but not, in fact, always hot. We had a pergola with a shady grape vine just outside our dining room. We had a Weber barbecue kettle to cook the turkey (roll) in. We had a Christmas Tree (albeit radiata pine which is much less satisfactory than European firs). We had a small swimming pool in the back garden. We had friends equipped with variations on this. 

Many of our friends had a cold Christmas lunch, including a “frozen Christmas pudding” (if I remember correctly; I wasn’t very keen on this concoction, too many nuts for me). But we always went for the hot option. The turkey was cooked outside, but the oven could go on for roast veg etc, provided the windows and double doors were wide open. And we could choose to eat inside or outside, depending on the weather. Very often there would be a late morning swim, with glasses of Australian “champagne” (as it was still called in those early days) nearby. One particularly memorable year we had our pre-lunch swim, terminated slightly early by a rare summer downpour as the “cool change” came swirling through, and the temperature dropped from 35 to 25 C. Move the table in through the double doors, but leave them open. Another glass of wine? Perfect!

The considerable disadvantage for us was that we were 12,000 miles from both our families, in the days well before email, Facetime, Zoom, or even affordable international phone calls. So we and our children were really completely cut off. I suspect we rather over-compensated in the presents department!

The best part of Christmas however wasn’t just the day. Nearly everyone was off work for the period from Christmas Day to New Years Day (my Institute was closed, so these days weren’t even included in my annual leave quota). The weather was warm to hot. The gardens were shady. The beach was inviting, the sea warm. The booze was good and cheap. Everyone visited. It was wonderful!

I wish all my readers (all 5 of you) a very merry Christmas, and a Happy New Year, wherever you are.

My life in computers 10 (*), Digital Equipment Corporation PDP-11

16 Dec
PDP11/40 as exhibited in Vienna Technical Museum

I didn’t think of writing a piece on the PDP-11 when I first planned this series. I’m not sure why. Maybe it was because I never had much directly to do with the PDP-11, being more involved in the “big-iron” end of the computing segment, as a programmer and as a manager. But it became clear as I was researching the series that the PDP-11 was very significant, and I’d just quietly forgotten that (not at all unusual these days, sadly… in fact, it’s partly the point of the series). For a start, I should have remembered that the PDP-11 played a significant part in our plans and achievements in networking access to the Cyber 173, in the SAENET context, as the Rusbridge/Heron Networking paper makes clear.

But the PDP-11s kept appearing in other contexts. For instance, the second issue of the SAENET Newsletter in June 1975 (prior to the arrival of the Cyber) quotes operating statistics for the ICL 1903A and the Institute’s two PDP-11/40s. The PDP-11/40s had 1220 users and ran 17,182 “programs” compared to the 1903A’s 1194 users and 16570 “programs” (the document reports them as programs, but really these were jobs). Over the January to May period that year, the 1903A had 1103 available hours out of 1329 switched-on hours, while the North Terrace PDP-11/40 had 3483 available hours out of 5322 switched-on hours. I quote these boring statistics to underline the significance of the PDP-11.

The 1903A, like the subsequent Cyber 173, was a big, relatively powerful computer requiring a proper computer room environment with significant air conditioning. The PDP-11s however ran in fairly ordinary office environments, with office air conditioning. They were probably kept in separate areas for security and other reasons. Despite this, they were more reliable, required much less maintenance and broke down (“un-scheduled maintenance) much less: roughly 1/5 of the un-scheduled maintenance hours, despite being switched on more than twice as many hours. Clearly DEC were doing something right. (By the way, the few months of Cyber statistics that were reported in the same fashion show much better reliability, although the switched-on hours were still well down on the PDP-11s, being limited to two shift day and evening operation.)

One feature of the PDP-11 was that DEC provided multiple operating systems, and several others were available. Within SAENET we used the RSTS time-sharing system, the RT-11 “real-time” system (on which the SAETAN software was based, and RSX-11, a multi-user “real time” system for process control and similar tasks. The PDP-11s were also famous, of course as being the computer on which the first version of Unix to be so named was installed.

According to Wikipedia, DEC was quite profligate in the design choices for its various minicomputer ranges. The article lists 7 different 12-bit models (including the PDP-8), 5 different 18-bit ranges, and 3 different 36-bit ranges culminating in the mainframe-like DECsystem-10. But they only had one 16-bit range, the PDP-11. And it was the most successful, with maybe 600,000 units sold, a huge number for those days (there’s a suggestion that the general move to the 8-bit byte rather than the 6-bit character was a strong part of the reason). This article from History Computer claims that the PDP-11 is still running a robot inside a GE nuclear power plant, and will do until 2050!

By the time the RFI for the Cyber replacement was published in 1981, SAENET Colleges had many PDP-11s. The document lists 8 systems used for SAETAN terminal and batch remote subsystems, 5 RSTS systems supporting a total of 77 terminals, a RSX-11 system for graphics and special purposes, and a RT-11 system running Multi-User BASIC. I am confident there were many more, such as the RSX-11 system run by Chem Tech, for instance. By comparison there are only a few other non-DEC minicomputers mentioned; the Data General Nova at Salisbury had (I think) by that stage gone, though there was a small Nova in Accountancy, a Basic/4 system in Business Management, and a Wang 2200 system in Surveying.

The DEC PDP-11 series was extraordinarily successful. However, at that time the ICL and CDC systems (and the like) were still regarded as “proper” computers, the PDP-lls at best as mini-computers. For a while we were fairly confident that minicomputers were the way of the future. We were, of course, wrong. But we were (then) content to ignore microcomputers as hobby systems, as games machines, or as chips to power word processors! Oh well…

  • Apparently I can’t count! This was intended to be My Life in Computers 9… I probably shouldn’t change it now. It’s going to be weird going back to 9 after 10, then I hope I remember to go on to 11!

My life in Computers 8f, SAENET Cyber 173: Whither SAENET?

10 Dec

A quote from the start of the last SAENET Newsletter:

“At its March meeting, SAENET Management Committee considered the future of SAENET in the light of the merger of four of its colleges to form the South Australian College of Advanced Education. The Committee made the momentous decision to recommend that the Colleges should establish their own separate organisations for the provision of computing facilities, and that SAENET in its present form should be disbanded at a date to be determined, subject to the availability of adequate capital funds for the replacement of the CDC Cyber 173 system.

“The Committee’s intention was that responsibility for provision of computing services would be progressively transferred from SAENET to the member Colleges from 1 January 1983; however, SAENET will continue to exist until at least 31 December, 1983 (and may be further extended beyond that date if we are unable to replace the Cyber by then). Since that meeting these recommendations have been accepted in principle by the three Councils involved.

“The recommendations clearly have major implications for the academic, administration and library staff who use SAENET services, and not least for the SAENET staff themselves.”

SAENET Newsletter, Vol 3 No 2, July 1982

A Request for Information (RFI) for the replacement of the Cyber system had been issued in December, 1981, but was unable to make commitments on the future of SAENET. In practice, the transition did begin during 1983, and the SAENET agreement did end at the end of December 1983. Most of the SAENET staff continued to be employed at SAIT, although the structure was slightly different. The first Computer Centre Bulletin (replacing the SAENET Newsletters) in early 1984 reported that the Cyber 173 was due to be switched off on 2nd November, 1984. “High maintenance costs make it unlikely that this closedown will be postponed, so it will be important to get computing-related projects in on time this year!”.

So what came next? Well, you’ll have to wait, as there are a couple of by-ways to be explored first!

My life in computers 8e, SAENET Cyber 173: Performance

9 Dec

Looking for information about the Cyber 173, I came across a rather eclectic site by Nick Glazzard, that I referred to earlier. He has a section about “Why some old computers are interesting“. Although he writes about other machines, it is mostly about the architecture of the CDC mainframes, including the Cyber 173. He also has a significant section about an emulator called DtCYBER, that runs on Windows or LINUX machines. It’s apparently a bare bones emulation of several Cyber mainframes, but the user has to supply the operating system!

Nick Glazzard ran a Cyber 173 emulator in DtCYBER on a 2000-era Intel PC. He doesn’t say what software he was using, though I speculate it was running on a version of NOS, based on other evidence on his page. He wrote (possibly in the early 2000s):

What sort of performance can you expect to get out of an emulated machine? Well, the CDC machines are a particularly difficult case. The PPs mean that the emulation has to be of an assembly of 11 processors instead of 1. Even so, the performance I have measured isn’t bad. The emulated machine runs about 350 times slower than the host machine. This can still be faster than the original hardware. For example, I run DtCyber on a dual 800MHz Intel P3 machine … and get about twice the performance of the real Cyber 173 that is being emulated. That is exponential performance improvement over 30+ years in action!”

If I understand that correctly, it looks like that PC was about 700 times faster than the Cyber, if that comparison makes any sense. Latest 2020 Intel processors are apparently around 100 times faster than that 2000-era Pentium, so today’s advanced desktops are probably running 70,000 times faster than the Cyber! Of course these super fast modern PC processors are weighed down by huge quantities of software bloat, so users don’t get to see quite that sort of performance improvement… but, thinking back, everything did take a very long time

My life in computers 8d, SAENET Cyber 173: disk space

7 Dec

When delivered, the Cyber had one 220 million character (Mcharacter) disk, and two 110 Mcharacter disks, for a total of 440 Mcharacters. The Request for Information for the Cyber replacement, dated December 1981, said the total nominal online capacity was “950 Mcharacters on 5 drives (another 240 Mcharacter drive is expected in 1982). Actual data storage on these drives in our environment is 400 Mcharacters. About another 1000 Mcharacters of data is stored offline on about twenty 120 Mcharacter removable packs.”

Despite continuing to add more drives, disk space was always a challenge, with much more demand than we could meet. Eventually we managed to install an “archiving system”, removing older and under-used files to tape. When it was introduced, Rollo Ross wrote this:

“Before we archived old files the first time, we searched for the oldest file on the Cyber disks. ‘HARRIPO’ was created by a SAIT Lecturer in November 1975, and was last used at 5pm on 26th November of that year. To put this in perspective, Australia was in turmoil at the time – Prime Minister Whitlam had just been dismissed by the Governor General following the constitutional crisis. The Concorde had not yet had its inaugural passenger flight, and petrol was only 13.1¢ a litre. HARRIPO has been going round and round 3600 times per minute for nearly four years, through system crashes, power failures, half a dozen system upgrades, dozens of disk reloads after writeoffs, hundreds of deadstarts, being lovingly preserved for an owner who probably forgot all about it in 1976. That file has now been archived to make way for new files whose owners, we hope, will be more conscious of our limited resources.”

SAENET Newsletter Vol 2 no 6, April 1980

Of course, pretty much whatever device you’re using to read this today, even a mobile phone, has much, much more disk space than we had on the Cyber, for a whole educational sector!

My life in computers 8c, SAENET Cyber 173: security

6 Dec

In our User’s Guide, we were a touch naïve about security. Above is a quote from the Guide suggesting that “you cannot harm the system by making incorrect entries…”. And even if you are  “unsuccessful at logging in to the system four times in succession, your terminal is automatically disconnected. If this happens, thoroughly check that you are using the correct procedure, check your assigned user number and password, and start again.” We should have guessed that the system was going to be exploited… but to be fair, the idea of “hacking” was at that time still in the future… a bit!

By May 1976, there was an article in “GNOSYS” (the more technical newsletter) about misuse of computing facilities. We stressed that games should not be played to the detriment of “serious work” (there were only around 40 terminals for the whole system at that time. We were also stressing that resources were there for the assigned user only. It seems that some users were using credentials belonging to others, and it also looks as if outsiders were getting access to SAENET resources. We may be used to an era where for most of us computing and storage space can appear as a limitless, free resource, but that was definitely NOT the case in those days. To emphasise this, that paragraph ended: “In ·some cases of misuse in the past, the culprits have lost allcomputing privileges”.

By mid 1977 a new element had been introduced:  “The system now maintains a count of how many unsuccessful attempts you have made to discover someone else’s password. When the account exceeds a certain limit, your user number becomes unavailable, and you can no longer use the machine. The systems programmers can overcome this, but we will do so only if you have a very convincing excuse.”

By mid 1979, we find a student whose password had been changed without his knowledge, denying him access to his account. Apparently repeated attempts had been made to login using different passwords. Soon afterwards, two students hd their computing privileges removed! The advice from Bob Northcote then was…

“…all users should ensure they have reasonably complicated passwords, of at least […. drum roll please…] two characters in length, to discourage attempts by others to ascertain them”

Two characters! Just 2 characters!!!

My life in computers 8b, SAENET Cyber 173: user publications

2 Dec

Since computers were generally so extraordinarily different from one another in those days, there was a real problem when you were migrating from one to a different model. In a business context, you would probably pay for some intensive training, but this would be mostly focused on your computing department, with more specific training coming on later for the application users. In an Institute of Technology setting the situation is rather different. While we rely on the academic staff to teach the students, there were hundreds of staff who would need to use the computers directly.

It seems we took this quite seriously. From the University of South Australia’s Library catalogue and other sources, I discovered the existence of a SAENET Cyber User’s Guide, as well as something called SAENET GNOSYS, and also a series of SAENET Newsletters. I was very lucky that a colleague who started work with us in 1980 (near the end of the Cyber era) is still working at the University (successor to SAIT), and I was in touch with him about some other matters. Stephen (Rocky) Stone agreed to get some of these documents from the Library’s archival store, and I asked him to scan a few pages for me. I was stunned (and very pleased) when he scanned the whole lot! Thank you, Rocky.

In one way that gave me a problem, as there was so much stuff to read and absorb, I didn’t quite know how to deal with it. By the way, as well as the University, the National Library of Australia seems to have copies of these documents as well, though neither has any digital copies.

As well as the documentation we produced, I gather we had a library of around 10 copies of the official Control Data manuals, but given that there were 8 campuses involved, you can see that wouldn’t go very far!

It appears the User’s Guide was written very quickly within a month or two of the arrival of the Cyber, by Rollo Ross, our extraordinary Systems Programmer. These and later posts partly celebrate his contributions and remember him, as he died only a few months ago. It was a pretty basic guide, more or less telling the user how to prepare a job, connect to the computer and so on, and with an almost identical chapter for each language subsystem the user might need to use. One of its most excellent features, which we adopted for most later documentation, was its simple, direct, second person style. Here are a couple of paragraphs from the opening:

The first 2 paragraphs of the SAENET Cyber User's Guide, 1976
SAENET Cyber User’s Guide, 1976

That gives you a flavour. I find this document interesting as well, in that it was printed on a very primitive printer, perhaps one of the very early dot-matrix printers. The characters are formed by 7×5 dots, and there are no “descenders”. It doesn’t make for an easy read, and definitely fares badly with OCR software!

Given that most of our users were relatively unfamiliar with accessing computers via terminals, we had to go into rather exhaustive detail about how to login, including how to end each command, how to correct errors etc. Most of the users would have been on Teletype printing terminals, as I showed previously, though a few early Visual Display Units were around. The printing terminals turned out to be part of one of the cost problems for us, as usage increased so much that it contributed to a large over-run in the paper budget. Many posts in the Newsletter discuss the problems stemming from our burgeoning consumables budgets!

Teletype 33
Teletype 33 CC-BY-SA Rama & Musée Bolo via Wikimedia Commons

I was very puzzled about GNOSYS, and without Rocky’s help I wouldn’t have been able to work out what it was about. It was described as “an irregular publication… to provide technical or urgent information to computer users.” The title came from “Gnosis: knowledge of spiritual mysteries”! Altogether 14 issues were produced, from April 1976 to November 1977. Oddly, items were numbered sequentially from no 1 in the first issue to number 100! Thankfully, we seem to have found a printer that could cope with descenders by this time, and the text is much more readable:

SAENET GONSYS, disk space crisis and policy
An early item in SAENET’s GNOSYS technical newsletter

A disk quota of 300 kilobytes!

Incidentally, the policy of purging files described in the paragraph above did not last long. In the 3rd issue, we printed a list of users with files that were candidates for purging, showing their names and “last used” dates. Basil Benjamin, on the of the Maths lecturers, was incensed at seeing so many of his files on the purge list; there were small files that he would probably use for classes once a year, and we wanted to purge them after 4 months! He asked for a dump of file sizes and access dates and produced an impressive analysis showing how our policy was very effective in annoying the maximum number of users, but was comparatively ineffective at freeing up disk space. He persuaded us to concentrate on large files first, and target the relatively few users who owned such files, working with them to help move the files off onto magnetic tape. Somehow this policy change didn’t get documented in GNOSYS!

The SAENET Newsletter, meanwhile, was intended to be more generally “newsy”, though it gradually took over the functions of GNOSYS. It was produced several times a year from February 1975 to March 1982. The last issue was a lengthy but rather tense issue announcing the end of SAENET and some concern about our futures. But that’s for another blog!

The design was pretty primitive at first, and the masthead went through several quite un-distinguished changes, before settling down to this:

SAENET Newsletter masthead in a font based on MICR
SAENET Newsletter masthead

That font would have instantly said “computer” to people in the late 1970s. It’s based on the Magnetic Ink Character Recognition (MICR) fonts, invented in the late 1950s to make the numbers on cheques machine-readable. The true MICR font consists only of the digits 0-9, but a number of fonts based on a similar style appeared not long afterwards. My very rigorous research (ie a bit of googling) did not find that exact font, but there are a few rather similar.

Later issues did add a bit more humour, and even a little bit of graphics, like this:

Getting things done here is like mating elephants! It's done at a high level, with a great deal of roaring and screaming, and takes 2 years to produce results!
Mating elephants… drawing by Ursula Ross

This last example is particularly poignant, written in 1982, and referring amongst other things to the birth of my son:

Verses in Celebration of SAENET, by Steve May

The author of these little verses, Steve May, was a young programmer who was supporting our Library users. His fiancée was a teacher, who had been required by the Education Dept to work in a “country” school (part of the conditions of the teaching grants in those days). Steve stayed with his family in town during the week, and went back up-country to stay with his fiancée over the weekend. Sadly, one weekend his motor-cycle was involved in a collision with a vehicle coming the other way, I believe when that vehicle was overtaking, and Steve was killed. I’m not sure how long after those verses were penned that this happened. It was, as you can imagine, a huge shock to the relatively tight-knit group of staff whom he depicts with such good humour. We missed him greatly. 

So this post is dedicated to the memory of Steve May and Rollo Ross.

“Network Development: some Achievements and Possibilities” 1978/79

26 Nov

[I found this article by David Heron and me amongst some old papers, and it’s partly what triggered off this whole series. The pages of typescript I have are numbered, and appear to come from conference proceedings, but are undated and don’t identify the conference. From other sources, I found “An annual Computing in CAEs Conference also ran from the late 1960s until the late 1980s. The papers presented at these conferences were lightly refereed in comparison with the ACJ, but the topics were of relevance to an analysis of the preoccupations of the profession and discipline at the time…” (from Clarke, Roger. (2008). A retrospective of the information systems discipline in Australia. 10.22459/ISADA.09.2008.02).  Since our paper refers to 1977 as the past, and late 1979 as the future, it seems likely it was written for the Computing in CAES conference in 1978 or early 1979. I have not been able to find the location or dates of the Computing in CAEs Conference for those years.

I include this article partly in memory of my late good friend David Heron, who died in 2010 after a long battle with Parkinson’s disease, and partly because it adds context to what we were trying to achieve in SAENET at that time. David wrote the sensible bits in the middle, and I suspect I was responsible for the waffly bits at the start and end. It is transcribed by me but otherwise unaltered from the original.]


Authors: D. L. HERON [Qualifications omitted]

C. A. RUSBRIDGE [Qualifications omitted]


ABSTRACT:  Localised communications networks have been a reality in Tertiary Education in various forms for some years. This paper discusses briefly the evolution of SAENET, which provides a computing service to C.A.E.’s in South Australia. The paper continues to consider future network developments, particularly the possibility and benefits of a nationwide network.


Computer networking has been a fashionable topic for many years now, although in many cases reality has fallen short of expectations. We believe that the continuing delays in some of our grander networking schemes have not been entirely detrimental; in the interim we at SAENET had had the opportunity to see a less well publicised side of networking in action – the organisational, or perhaps the sharingaspects of a network. Some of the wise men from the East are beginning to remind us that the foreseeable trends in computer hardware and telecommunications costs mean that the early justification for networking (sharing the cost of a powerful system amongst many users) will no longer apply even in the medium term future. However, we are also reminded that other factors (largely human factors) can still justify the cost of the network. We are referring to benefits some of which come from normal timesharing systems, such as sharing the cost of installing and supporting the operating system and applications software; development of common computer systems; access to specialist skills available in a computer centre; access to programs developed by other users; automated mail, gripe, help and even perhaps teleconferencing; and not least the economies of scale obtained in bulk purchase of supplies, negotiation of maintenance contracts, and so on. In this paper, while we will touch on the hardware and software aspects of networks, we will also cover these human aspects.


SAENET (the South Australian Advanced Education Computer Network) was conceived – we are led to believe – on a red table napkin in Maggie’s Restaurant in Adelaide in 1974. Early growth included an informal agreement between the 8 member Colleges (see Appendix) in 1975, and the delivery of our Cyber in November of that year. As child psychologists (and parents?) might predict, some three years later we are very much concerned with clarifying our identity and formalising our relations with parent bodies, through the current development of a more formal agreement, known as the SAENET Indenture.

The SAENET Indenture is currently being vetted by the Colleges before being checked over by legal experts. It is a serious attempt to formalise the relationships between member Colleges, defining their rights and responsibilities, and SAENET’s obligations to them. It commits SAENET to a rolling triennial budget, and commits the Colleges to share the costs in a well-defined way related to the amount of use the Colleges expect to make of SAENET facilities.

Before the Cyber was delivered, four of the CAEs took delivery of PDP11/10 minicomputers, which they were to use for running Multi-user Basic under RT11, with 2-5 terminals. The S. A. Institute of Technology had at that time a RSTS/E system on a PDP11/40 at North Terrace, and a GEORGE 3 system running on a 1903A at the Levels(the latter has since been closed down). Salisbury CAE had a Nova system; they have not benefitted as much as the other Colleges from the central support offered by SAENET, and the bulk negotiation of supplies and maintenance contracts. The two smallest Colleges had no computing facilities at all.

Most colleges soon acquired 300 bps dial-up terminals, which were used to access the Cyber for academic and administrative purposes. In most cases the bulk of the load from the Colleges other than the Institute derives from the use of common administrative packages developed by SAENET. These are the Employee system and the Student Records system; the latter is described in other papers to be given at this Conference. Remote job entry programs for the PDP11s were developed at an early stage, and have since been re-vamped; the Colleges run their RJE through 1200 bps dial-up modems, except for the Institute North Terrace campus and Salisbury CAE which both use 4800 bps leased lines. A special RJE system had to be written for Salisbury (moral: the costs of a lack of standardisation have been high and will continue).

The Institute North Terrace campus has received a big boost in available computer resources with its RJE system, even though turnaround times range up to 7 hours, largely due to a 300 lpm printer struggling with lots of COBOL. North Terrace users have only restricted interactive access to the Cyber through dial-up terminals, usually locked away in staff offices.

The Geographical layout of SAENET member Colleges

The advantages to date of our approach, compared with ‘go-it-alone’ solutions for the eight Colleges, have been principally in the following areas:

  • Management Services, including particularly supplies, maintenance contract negotiation, in-house maintenance of some terminals, Telecom negotiation, procurement advice, data preparation facilities, etc.
  • Programming support, including RT11 and Multi-user Basic, duty programming, access to a wide range of experience amongst our dozen or so programming staff.
  • Common systems, such as the Remote Job Entry system, and the Common Employee and Student Record Systems. The latter has greatly eased the production of TEC statistics, for example, and provides a consistent interpretation through all South Australian CAEs. Common Library systems are also under development, initially involving services from the Melbourne bureau Libramatic Systems.
  • Use of number-crunching capability, and wide range of applications packages and languages available on the Cyber.

Goodwill, although not normally a commodity much considered by Computer Centres, has been satisfying. This has required some gymnastics, to avoid appearances of preference to our largest (and on-site) user body – the Institute at the Levels campus. We try to remember that we are not an Institute body doing a little work for the Colleges, but a College body which happens to have the Institute as its largest customer. We believe that this attitude is vital to the success of the operation, and it is reflected in the composition of our governing Policy and Management Committee, which has on representative – and hence, one vote – from each College, despite the great disparity in financial contributions.

Perhaps our most significant failure, when looking at our early aims, is the lack of interest in using the central computing facility shown by academics in the smaller Colleges. A result of the lack of interest is a certain amount of mistrust by College academics of SAENET – what does it do for them with all that money? In contrast, the administrators appear to be well pleased. This failure we attribute to the difficulty of access, particularly interactive access, compared to the local Multi-User Basic systems. This difficulty of interactive access is partly the result of protracted delays in the full network software. Our resources do not allow us to modify manufacturer’s software to the extent required to add remote concentrator support to the Cyber operating system, NOS; the promised networking software from both our equipment suppliers has been delayed for several years now. At last, we believe the crucial software will be delivered within weeks, and we hope that the developments on which we are working will provide a better service to our off-campus academic users, and convince them that we do indeed provide ‘value for money’.

Present developments – the terminal concentrator

With news of the impending arrival of the vital manufacturer’s communications software, the decision to develop our concentrator software, SAETAN (derived from “SAENET Access Node”) was taken. As this is a long term project, we are meanwhile making some further improvements to our RJE programs, including providing facilities for the transfer of files between the Cyber and the PDP11, and possibly simultaneously running of RJE in the foreground with Multi-User Basic in the background. These developments are based on a program (RBT) obtained from the University of New South Wales.

The aim on the SAETAN software is to support simultaneous terminal concentration and remote job entry on the one computer. It will use a bit-oriented protocol called CDCCP, similar to the ISO HDLC protocol. The design of the SAETAN executive has been proved out in the development of the Nova RJE system in 1977. In retrospect, we might have been better off rewriting our PDP11 RJE in 1977 using the SAETAN design; however, the executive and development tools have now been written and tested for the PDP11. It is noteworthy that a common design has been evolved for both PDP11 and Nova implementation. The design is highly modular, well documented and intended to be easy to maintain yet (touch wood) efficient enough to handle about 10 terminals, card reader and line printer (up to 30 terminal if DMA peripherals are used for terminal interfacing and driving the synchronous line).

The implementation language is Macro-11, using a rich set of Structure Programming Macros developed by David Heron. The detailed contents of many parts of the system are unknown at this stage; most uncertainty surrounds the message protocol handler, for which complete interface documentation is not yet available. However, we hope to have the necessary information for all parts of the system shortly, and there should be no delay in the expected completion date (end 1979). The completion date would be considerable earlier if we had access to a development machine; at present all development is done on the Cyber using cross-assemblers and cross-linkers. The resultant absolute PDP11 program is transmitted downline to the Chemical Technology PDP11/40 for test sessions when it is available. This is a slow and cumbersome development process; its only virtue is that it encourages desk-checking!

We believe that SAETAN will be installed first at the Institute at North Terrace. Because of the full duplex, efficient protocol, RJE throughput can be much greater for the same line speed; we should also be able to support multiple line printers on the node. Other Colleges will install the system as they become convinced of its merits. Some Colleges may wish to stay with their current RJE systems for some time, to save telecommunications costs, since CDCCP needs full-duplex lines, which are not available through dial-up synchronous service. Other Colleges may wish to expand their local systems, particularly if it became possible to run SAETAN simultaneously with some form of local timesharing Basic. Our aim here is not to force users onto the central computing system, but rather to increase the choices available to them.

A simple network configuration with SAETAN

Future possibilities – the Institute

The availability and capabilities of SAETAN have interesting implications for the Institute. Unlike the other Colleges, the Institute has many separate computer systems, ranging from micros and PDP8s. through PDP11/40s running RSX-11M and RSTS/E, to the Cyber. Access to computing facilities on the three Institute campuses is very different. North Terrace has RJE and 6 dial-up terminals to the Cyber, plus about 16 terminals to RSTS/E; the Levels has local Cyber batch and about 40 Cyber terminals, plus miscellaneous special-purpose computers; Whyalla has one hard copy terminal on a part-time leased line to the Cyber, with a small PDP11/34 RT11 and MONECS system on order. SAENET has proposed a plan to the Institute which, using a small further development of SAETAN in 3 concentrators running in small PDP11s, would in its ultimate deployment allow any Institute terminal on any of the 3 campuses access either to the Cyber or to a (developed) RSTS system. We believe that such a system would provide markedly better service, with the availability from all locations of either a system tailored to the needs of the beginning user, or a larger ‘number-crunching’ system. The good editing facilities of RSTS, together with easy transfer of files to and from the Cyber, can result in use of the network as an effective ‘conversational RJE’ system for those that prefer it. The present disparity of facilities between campuses should disappear; staff and students moving between campuses will find they are not disadvantaged.

Possible ‘multi-host’ configuration

This concept, for using a network of SAETAN concentrators with either host computer systems or terminals, card readers and line printers, could if desired be extended to include other computers in South Australia; however we have no intentions in that direction at this stage.

Further Future Possibilities

It seems inevitable that, within a timescale of 5-10 years from now, tertiary institutions must be able to access a national network. Again, the justification will not be the old economy of scale argument, in which everyone runs all their computing on a vast central machine (a la CSIRO); but rather to provide occasional access to people and resources not available at the home site.

In strong contrast to hardware and telecommunications costs the costs of writing, of buying and of supporting complex applications and other software is [sic] large and growing. The implications of this are that users in many Colleges will have to look outside their local computer system for the less frequently-used applications, and that the authors of educational packages will save the education system money by putting the extra effort into development and support to allow them to be used nationally (if they are good enough). An idea that we support very strongly is the inventory of administrative systems in Australian Universities, prepared by the Vice Chancellors Committee; we believe that a comparable inventory should be prepared for administrative systems in CAEs.

We believe that educational users cannot afford the high costs of a dedicated national network; but that they also cannot afford the high cost (in system development and the lack of software for teaching and research) of not having access to a national network at all. A case in point is data base systems. Clearly, those institutions seriously involved in teaching programming must teach data base methods. However, they are very expensive; software costs are about $20-30K. If appropriate network facilities are available, the Australian educational system has the potential to save considerable amounts of money by accessing for project work the data base systems at sites which have other justifications for them. Similar arguments apply to large linear programming packages, costing up to $40K.

Some mechanism is needed whereby temporary connections may be established for both interactive and batch use of computers systems situated in a variety of tertiary institutions anywhere in Australia; this is required before the mid 1980s, with the appropriate management structures for budgeting, billing etc. Given that it is hard to foresee implementation of a dedicated education network in Australia at a justifiable cost, the most likely means of achieving this is for tertiary Institutions to access a public data network similar to those available in North America and Europe; this almost certainly will depend on perhaps overdue initiatives from Telecom Australia in making such a service available with suitable tariffs and conditions of use.


The 8 member Colleges of SAENET are:

Adelaide CAE

Kingston CAE

Murray Park CAE

Roseworthy [Agricultural College]

Salisbury CAE

S. A. Institute of Technology

Sturt CAE

Torrens CAE

[pp 224-232]

My life in computers 8a, Control Data Cyber 173 at SAENET

25 Nov

In May 1975 I started work back at the SA Institute of Technology. It felt like coming home! I was working on the same floor of the same building as the SDC days, with many of the same people. My boss was once again Dr Bob Northcote, who was Director of SAENET and also (I believe) Head of Computer Studies. I was appointed as Programming Services Manager, SAENET, located at The Levels campus (now the Mawson Lakes campus of the University of South Australia).

So what was SAENET? This quote from a conference paper explains it a bit:

“SAENET (the South Australian Advanced Education Computer Network) was conceived – we are led to believe – on a red table napkin in Maggie’s Restaurant in Adelaide in 1974. Early growth included an informal agreement between the 8 member Colleges […] in 1975, and the delivery of [the] Cyber in November of that year.”(Heron & Rusbridge, 1978)

The Institute (which had 3 campuses: North Terrace in the city, The Levels in the northern suburbs, and the small Whyalla campus far to the north west) was by far the largest College; there were also 6 small Colleges of Advanced Education (CAEs) spread around the city suburbs, and Roseworthy Agricultural College some 40 km north. The CAEs were developed from teaching and art colleges that had grown up since the early years of the State. The idea was that SAENET would support these colleges not only by providing access to large scale computing resources, but also by other services such as maintenance contract negotiation, supplies, and applications systems.

The CYBER 173 had been ordered in late 1974, before I arrived, but not delivered until November 1975. Meanwhile, the 1903A GEORGE 3 system continued running until the end of the 1975 academic year (early December, I think). 

Here is a quote from the press release on the CYBER order written up in “Between Ourselves”, the Control Data Australia internal newsletter (thanks again to Lyndon Aistrope, ex Control Data engineer):

“The CYBER, which will be installed at SAIT’s suburban campus […], will have Australia’s first 2550 Host Communications processor and will use the new Network Operating System.

“It will be linked to mini-computers at SAIT’s city campus and six other colleges of advanced education to provide simultaneous remote job entry and interactive computing facilities.”

The Cyber 173 was a big, powerful computer for such a relatively modest institute, and it was quite a coup for SAENET Director Bob Northcote (who I am sure was at that table in Maggie’s Restaurant, no doubt sketching with his pen on that red napkin!).

The CDC Cyber 170 series were apparently (**) integrated circuit re-implementations of the CDC 6600/7600 (designed by Seymour Cray… “his designs were the fastest general purpose computers in the world for at least 20 years – from 1964 to 1984. The 7600 will probably forever hold the record for being the fastest available general-purpose computer for a longer time than any other machine type – 1969 to 1975”, according to Nick Glazzard). However the Cyber 173 was one of the lower end machines in the range, lacking some of the hardware of the faster machines. The Cyber computers had a unique design, with a CPU and separate Peripheral Processors (PPs) (our machine had 10). Apparently quite a bit of the Operating System ran in the PPs, which as their name implies handled all the peripherals.

The users saw a CPU system with 60-bit words, and 6-bit characters. The 18-bit addresses meant a limit of 256K (262,144) words! We had a 64K word machine at delivery. I do remember getting funding later on for a memory extension of 100,000 words… but that was much less than it sounded, as for some bizarre reason it was counted in octal (base 8), so really 32K (32,768) words, a 50% memory increase (another extension was installed later, taking it to 128K words, or just about 1M characters). I have a hazy memory that that first extension cost around A$100,000, but I might be making that up!

That memory was incredibly piffling by today’s standards, but even at delivery we had considerably more main memory than we’d been used to in the 1903A.

We also had one 200 million character disk drive, and two 100 million character drives, all exchangeable, plus one 7-track and two 9-track magnetic tape drives, a card reader, line printer and graph plotter.

If you’re interested in pictures of the installation process for large CDC computers, there’s an interesting post on Museum Waalsdorf’s site with pictures showing the installation of a Cyber 74 (I think at TNO). This was an earlier system than our Cyber 173. That article reminded me that the Cyber was water-cooled, and required an expensive upgrade of the cooling system for the computer room.

The Cyber of course was a massive machine that lived in an air-conditioned machine room with a false floor for all the cabling, normally tended by white-coated operators. However, this photo from Greg O’Connell shows an evening debug session with two of the Comms Team staff (that’s David Heron on the phone, Helen Roberts at the operators’ console, and Greg, presumably taking the photo), no operators in sight. Wisely, they wouldn’t let me in there on my own!

** Lyndon Aistrope writes:

“The CDC Cyber 170 series was an ECL (integrated circuit) implementation of the Cyber 70 computer line designed and built in Canada.

“The line was composed of lower Cyber (171 – 174) based on the original 6400/6500 and the upper Cyber (175 – 176) and based 0n the original 6600/7600 designed by Seymour Cray.

“You may point your readers to the ExCDA website for a mostly complete set of photographs of CDC systems (available for all to read)”

More to follow…

UK 2020/21 Influenza vaccination programme failure: letter to my MP

16 Oct

Dear Mr Wright,

What has gone wrong with the flu vaccinations programme [in England]? It appears there are no (or very limited) stocks of vaccines available, despite Prof Chris Whitty’s conclusion in his letter of 4 August this year: “This year, more than ever, we need to protect those most at risk from flu.”

I am a constituent of yours, living at […], Kenilworth. I write to you today about the shocking scandal of the non-availability of the influenza vaccine. Not enough has been said about this, despite the obvious fact that it augurs ill for the Government’s ability to roll out a nationwide coronavirus vaccine.

[The] Medical Centre in Kenilworth offered one clinic for the flu vaccine, on 19 September; unfortunately we were away at the time. We didn’t worry; in previous years they have offered several clinics, and there were alternative options at local pharmacies. However, on return, it appears they cannot offer new clinics as there are no (or very low) stocks available in the country. I tried our local Boots; no stocks in the company. Online I have several times tried Boots, Lloyds and Dudley Taylor. None are open for booking flu jabs.

This week my wife went to see her doctor about another matter, and while there, asked her doctor about the flu jab. The doctor called the nurse, and she was given the vaccine on the spot; the doctor advised that I should call for an appointment. I tried the next day, to be told no, they could not offer me the vaccine as the limited stocks available were reserved for the most needy patients. As a [mid 70s] with asthma, that didn’t include me; I’d need to “upgrade” to COPD to get vaccinated against flu… in a year of pandemic!

I was told they are trying to get stocks to offer more clinics. They were not sure when (or whether) this would happen; it could be next day, next week, or next month (or not). I should check online or with the surgery on a regular basis!

I understand that this year eligibility for the flu vaccine has been extended to the 50-64 age bracket. I wonder if this increased eligibility has anything to do with the low availability? Could the government have failed to take into account the impact of increasing eligibility on age brackets already at risk? Can they have failed to anticipate demand in a pandemic and failed to order sufficient stocks?

I don’t suppose we’ll ever learn the answers to those questions from this famously opaque government. But I would very much like to know the answers to the following questions:

When will there be sufficient stocks of the influenza vaccine for all those in the over 65 cohort to get vaccinated?

Will it be early enough to stop a flu outbreak compounding the effects of Covid-19 infection in this age group, and increasing the overload on our hospitals?

What does this mean for the future distribution of coronavirus vaccines in the community?

Yours sincerely

Chris Rusbridge

PS I plan to post a copy of this letter on my blog unsustainableideas.wordpress.com, and would like to publish your reply with your permission. Thank you

See the letter from Prof Whitty dated 4 August, 2020 at https://www.england.nhs.uk/wp-content/uploads/2020/05/Letter_AnnualFlu_2020-21_20200805.pdf

“18. As usual, providers will have ordered flu vaccine directly from manufacturers. This season, we are expecting increased demand for flu vaccine across all cohorts and we are also expanding the flu programme. To support this, the Department of Health and Social Care (DHSC) has procured additional national supply of the adult vaccine and will issue guidance in September on how and when this can be accessed.”

“21. This year, we are asking for a concerted effort to significantly increase flu vaccination coverage and achieve a minimum 75% uptake across all eligible groups. Where possible, we expect uptake will be higher than this and a national supply of stock has been procured to ensure demand does not outstrip supply.

“22. Many of the groups who are vulnerable to flu are also more vulnerable to COVID-19. Not only do we want to help protect those most at risk of flu, but also protect the health of those who are vulnerable to hospitalisation and death from COVID-19 by ensuring they do not get flu.”

“40. This year, more than ever, we need to protect those most at risk from flu. Thank you for all your hard work in these very challenging times.”

From Appendix A

“1. In 2020/21, flu vaccinations will be offered under the NHS flu vaccination programme to the following groups: 

  • all children aged two to eleven (but not twelve years or older) on 31 August 2020 
  • people aged 65 years or over (including those becoming age 65 years by 31 March 2021) 
  • …”