Rope Memory

[knucracker]

Ever heard of rope memory?  Watch this if you have not...
http://mentalfloss.com/article/52297/computer-put-men-moon

Makes me want to wire some up and put a USB interface on it :)

[Grauniad]

I had a piece of ferrite core memory once. I wonder what happened to it.

[Kingo]

Looks interesting :)

[Grauniad]

I keep thinking about this. That wasn't "rope memory" as much as "programs on a string". They hardwired program codes onto those strings, note where they describe how the wires passing onside or outside the cores was a binary 1 or a binary 0.   Normal core memory with ferrite cores could turn on or off the bits, and it was (briefly) non-volatile (if memory serves) since the magnetization persisted. That was why old mainframes has two boot sequences - Boot and clear boot. Clear boot went through and cleared residual memory effects from core - just in case the programming was sloppy and referenced uninitialized storage locations.

[knucracker]

Yeah, I had never heard of this before and initially confused it with core memory.  This is ROM and the LOL's literally wove the bits together.  Incredibly inefficient, heavy, slow... but super fault tolerant.  Cosmic rays and solar flare radiation wouldn't flip any of those bits :)  (Though I imagine induced currents in the wires could cause you to read the wrong values for a moment).

Those dudes in white shirts and black ties did what they had to do with what they had to do it with.  Easy to say (sorta) but something not so easy to do in modern times.

Speaking of oddball memory, a few years back I wondered how much data you could store as EM radiation in space.  No, I'm not talking about the holographic principle and the limits of information storage in a region of space.  Imagine this;  You have two hands and each can store 1 bit of information.  Each hand can either hold a bowling pin with either a 0 on it or a 1 on it.  Now a juggler enters the room and juggles 3 bowling pins round and round in sequence.  The juggler only has two hands but has access to 3 bits of information.  He can only access 2 bits at a time, but the bits roll around quickly.

So, build a radio transmitter and a receiver.  Between the two is X bits of storage.  Transmit the data from storage to something remote like the moon, bounce it off the moon, then receive the signal at your receiver and feed the data into the memory.  This forms a giant loop with the amount of storage in the loop being based on the data transmission rate and the size of the loop.  In almost any case where the loop is large, the loop storage will significantly exceed the local memory.  In principle you only have to have 1 bit of local storage between the receiver and transmitter, but could store megabits in the EM loop.

Sure, this 'juggle drive' is filled with errors, has very high access latency, etc... lots of practical issues.  Probably better to focus my thoughts on my ICMP drive idea where I use routers of the world to store information :)

[thepenguin]

I've thought about it before. Using the undersea cables for memory, albeit not much.

If you managed to define a very roundabout way of routing packets, it might be possible on the internet, assuming no downtime on the network (you might lose it all if your modem breaks and you aren't up to receive the data, though...)

[Neko187]

you'd have redundancies and several relays...
It might be more possible in a low-pressure environment and through the use of multiple different frequencies in the same area... issue is the exponential nature of decoding overlapping signals...

[thepenguin]

you'd have redundancies and several relays...
It might be more possible in a low-pressure environment and through the use of multiple different frequencies in the same area... issue is the exponential nature of decoding overlapping signals...

all you need is a solution to fourier transforms...

[Cavemaniac]

This put me in mind of a system I first read about in a truly astonishing book (more in a moment) where early computers used vast tanks of mercury to store information in - a type of Delay Line Memory.

http://en.m.wikipedia.org/wiki/Delay_line_memory

If you're interested in the early days of computing I highly recommend:

A Computer Called Leo

It's both interesting and informative - I don't read a lot of non fiction but I heard an excerpt read out on BBC Radio 4 while I was living in the UK and I was so enthraled that immediately ordered a copy from amazon.

They seem to have it in the 'States so you shouldn't have too much difficulty finding it.

http://www.amazon.com/gp/aw/d/1841151866

However, it's a hell of a lot cheaper in the UK.

http://www.amazon.co.uk/gp/aw/d/1841151866

[Cruster]

Anyone remember bubble memory? http://en.wikipedia.org/wiki/Bubble_memory

[Kingo]

Anyone remember bubble memory? http://en.wikipedia.org/wiki/Bubble_memory

Won't the action of moving them around magnetically erase their data?
Unless the reader bit is moving and the data is staying in place...
Interesting stuff :)