A map of the internet found from 1973

It got bigger quite rapidly. My wife started sending e-mails from England to her friend at MIT from around 1980 (though she did have to type in very long addresses).

A few years later we were swapping shopping lists across Cambridge via the Rutherford Appleton Laboratory in Oxforshire, where I had log-in.

Interesting.

I saw a lot of PDP-11s but never a PDP-10. I also remember the acoustic couplers on modems. You placed a phone in a holding yoke and dialled, and got the famous crackle-crackle of modem-handshakes.

Ed

In the wrong direction. It doesn't seem to have survived, and if a a had any part in it, one can understand why.

You needed the right shape of handset to fit the acoustic coupler. But they didn't start messing with the physical details, until the era where third parties were "allowed" to make phones. At one time, only Bell equipment could be connected to a Bell line. The Bell phones had the "rounded earpiece" suited to the acoustic coupler.

My company was lucky. The bsovax had a direct line to the european backbone. My address was mcvax!bsovax!albert

Groetjes Albert

I remember being shown an accoustic coupler and telephone handset. The two programmers using it took the mickey by trying to persuade me that they could give a computer instructions by simply talking to it. Who did they think would ever believe that?

I'm reminded that this was the setup where I was once required to do a late shift alone doing some pretty mind-numbing data entry, and I was bored out of my mind. The system (PDP-8 with a BASIC command interpreter, I think?) stopped, and I didn't know how to restart it - nothing on the help-sheet actually helped. I'd not sat at a terminal many times before this, and I found I could type all sorts of nonsense into it (unprintable, mainly) and get stupid error messages back. Until I typed "Go To Hell". It all started up again as if by magic. I finished my shift and left. Three months later they discovered the entire dataset from the last six months was utterly scrambled. How could that have happened?

Yeah, that was the format.

I don't know if TCP/IP existed back then or not. Or Domain Name Service.

Paul

Late 1970s, county of East Sussex, UK. I worked as an in-house programmer at a vast government computer site. There were some contract programmers working there too, twice our salaries but they got all the maintenance work while we were developing a large new system on several ICL mainframes. The contractors got sacked. A couple of days later we discovered that some files had been erased. After much investigation we found that it had been done from a public phone-box, using a portable work-station with an acoustic coupler on the side, that the contractors carried around with them. And the public phone-boxes at the time had phones exactly like the one in your picture.

We never convicted them; lack of proof. But we all knew, and we knew which one of them was the most likely culprit.

Ed

I have an older relative who got an implanted pacemaker about 1992. The device she had to send data from it to the hospital used an acoustic coupler, although that one did work with the cordless phone.

Being a member of the CMU community since 1975, I was sending emails and assembler files (pdp11) to my thesis advisor and other members of our team as far back as 1977 IIRC. A number of CMU faculty were part of DEC sponsored research projects. The central campus computing resources at that time consisted of a number of IBM 360s and 370s but in our labs we had PDP11s and PDP10s. When on the hunt for a dedicated machine for our work, my office mate said....just go looking around, this place uses PDP11s as door stops...fun times. One of the other groups doing the networking work and an IMP, but I never ventured into that lab.

Why were those handshakes so long? Did they include tests ate different baud rates to see which worked ok?

On Feb 24, 2023 at 11:49:12 PM MST, ""Commander Kinsey"" wrote snipped-for-privacy@ryzen.home:

Yes. They went back and forth to find what they could support that would be best.

At the time I could hear different tones and know at least some of what was being tested.

that's long after what existed in the days of a pdp-11, which was simple fsk and a quick handshake.

Of course not. The question was asked, why dialup could have long sequences involving "different noise sets", and it is negotiation and communication going on. That picture shows some examples.

The modulation at low rates was a lot simpler, but if equipment at the ends have different capabilities, they would still need to negotiate and agree to a common rate. If I had a 1200 baud DecWriter on a 300 baud modem pool port, something would have to give.

Some mechanical devices even had timing issues, and the way that material was sent had to be controlled. A teletype probably did not have a buffer onboard, and you had to allow several character times for a carriage return to happen. There might be a difference between driving a glass tube at

Most all of the teletypes I used in university, were hardwired, and there was nothing acoustic there. Things like loaner equipment, could have the acoustic coupler.

the first glass terminals around that time, were using shift registers instead of static RAM for the display. It might have been NMOS shift registers. The horror. I guess there were no mercury delay lines left in the stockroom :-)

Paul

in the days of a pdp-11, negotiation was quick.

obviously the modern complex protocols need more time.

it's not just modems. early websites, which were almost entirely text with a few (small) images loaded quickly. modern ones with dynamic content and multiple scripts take more time.

those protocols were simple and the difference in time between 300 and

completely irrelevant to modem negotiation.

Dial-up modems (remember those?) and fax machines all do that.

Cheers

Phil Hobbs

On Feb 25, 2023 at 9:34:35 AM MST, "Phil Hobbs" wrote snipped-for-privacy@electrooptical.net:

Yes. That is what I was referring to. Though the fax sound is even more painful to listen to.