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Evolving Computer Words: “Broadband”

This is part of a series of posts on computer terminology whose popular meaning – determined by surveying my friends – has significantly diverged from its original/technical one. Read more evolving words…

Until the 17th century, to “fathom” something was to embrace it. Nowadays, it’s more likely to refer to your understanding of something in depth. The migration came via the similarly-named imperial unit of measurement, which was originally defined as the span of a man’s outstretched arms, so you can understand how we got from one to the other. But you know what I can’t fathom? Broadband.

Woman hugging a dalmatian. Photo by Daria Shevtsova from Pexels.
I can’t fathom dalmatians. But this woman can.

Broadband Internet access has become almost ubiquitous over the last decade and a half, but ask people to define “broadband” and they have a very specific idea about what it means. It’s not the technical definition, and this re-invention of the word can cause problems.

Broadband

What people think it means

High-speed, always-on Internet access.

What it originally meant

Communications channel capable of multiple different traffic types simultaneously.

The Past

Throughout the 19th century, optical (semaphore) telegraph networks gave way to the new-fangled electrical telegraph, which not only worked regardless of the weather but resulted in significantly faster transmission. “Faster” here means two distinct things: latency – how long it takes a message to reach its destination, and bandwidth – how much information can be transmitted at once. If you’re having difficulty understanding the difference, consider this: a man on a horse might be faster than a telegraph if the size of the message is big enough because a backpack full of scrolls has greater bandwidth than a Morse code pedal, but the latency of an electrical wire beats land transport every time. Or as Andrew S. Tanenbaum famously put it: Never underestimate the bandwidth of a station wagon full of tapes hurtling down the highway.

Telephone-to-heliograph conversion circa 1912.
There were transitional periods. This man, photographed in 1912, is relaying a telephone message into a heliograph. I’m not sure what message he’s transmitting, but I’m guessing it ends with a hashtag.

Telegraph companies were keen to be able to increase their bandwidth – that is, to get more messages on the wire – and this was achieved by multiplexing. The simplest approach, time-division multiplexing, involves messages (or parts of messages) “taking turns”, and doesn’t actually increase bandwidth at all: although it does improve the perception of speed by giving recipients the start of their messages early on. A variety of other multiplexing techniques were (and continue to be) explored, but the one that’s most-interesting to us right now was called acoustic telegraphy: today, we’d call it frequency-division multiplexing.

What if, asked folks-you’ll-have-heard-of like Thomas Edison and Alexander Graham Bell, we were to send telegraph messages down the line at different frequencies. Some beeps and bips would be high tones, and some would be low tones, and a machine at the receiving end could separate them out again (so long as you chose your frequencies carefully, to avoid harmonic distortion). As might be clear from the names I dropped earlier, this approach – sending sound down a telegraph wire – ultimately led to the invention of the telephone. Hurrah, I’m sure they all immediately called one another to say, our efforts to create a higher-bandwidth medium for telegrams has accidentally resulted in a lower-bandwidth (but more-convenient!) way for people to communicate. Job’s a good ‘un.

Electro-acoustic telegraph "tuning fork".
If this part of Edison’s 1878 patent looks like a tuning fork, that’s not a coincidence. These early multiplexers made distinct humming sounds as they operated, owing to the movement of the synchronised forks within.

Most electronic communications systems that have ever existed have been narrowband: they’ve been capable of only a single kind of transmission at a time. Even if you’re multiplexing a dozen different frequencies to carry a dozen different telegraph messages at once, you’re still only transmitting telegraph messages. For the most part, that’s fine: we’re pretty clever and we can find workarounds when we need them. For example, when we started wanting to be able to send data to one another (because computers are cool now) over telephone wires (which are conveniently everywhere), we did so by teaching our computers to make sounds and understand one another’s sounds. If you’re old enough to have heard a fax machine call a landline or, better yet used a dial-up modem, you know what I’m talking about.

As the Internet became more and more critical to business and home life, and the limitations (of bandwidth and convenience) of dial-up access became increasingly questionable, a better solution was needed. Bringing broadband to Internet access was necessary, but the technologies involved weren’t revolutionary: they were just the result of the application of a little imagination.

Dawson can't use the Internet because someone's on the phone.
I’ve felt your pain, Dawson. I’ve felt your pain.

We’d seen this kind of imagination before. Consider teletext, for example (for those of you too young to remember teletext, it was a standard for browsing pages of text and simple graphics using an 70s-90s analogue television), which is – strictly speaking – a broadband technology. Teletext works by embedding pages of digital data, encoded in an analogue stream, in the otherwise-“wasted” space in-between frames of broadcast video. When you told your television to show you a particular page, either by entering its three-digit number or by following one of four colour-coded hyperlinks, your television would wait until the page you were looking for came around again in the broadcast stream, decode it, and show it to you.

Teletext was, fundamentally, broadband. In addition to carrying television pictures and audio, the same radio wave was being used to transmit text: not pictures of text, but encoded characters. Analogue subtitles (which used basically the same technology): also broadband. Broadband doesn’t have to mean “Internet access”, and indeed for much of its history, it hasn’t.

Ceefax news article from 29 October 1988, about a cancelled Soviet shuttle launch.
My family started getting our news via broadband in about 1985. Not broadband Internet, but broadband nonetheless.

Here in the UK, ISDN (from 1988!) and later ADSL would be the first widespread technologies to provide broadband data connections over the copper wires simultaneously used to carry telephone calls. ADSL does this in basically the same way as Edison and Bell’s acoustic telegraphy: a portion of the available frequencies (usually the first 4MHz) is reserved for telephone calls, followed by a no-mans-land band, followed by two frequency bands of different sizes (hence the asymmetry: the A in ADSL) for up- and downstream data. This, at last, allowed true “broadband Internet”.

But was it fast? Well, relative to dial-up, certainly… but the essential nature of broadband technologies is that they share the bandwidth with other services. A connection that doesn’t have to share will always have more bandwidth, all other things being equal! Leased lines, despite technically being a narrowband technology, necessarily outperform broadband connections having the same total bandwidth because they don’t have to share it with other services. And don’t forget that not all speed is created equal: satellite Internet access is a narrowband technology with excellent bandwidth… but sometimes-problematic latency issues!

ADSL microfilter
Did you have one of these tucked behind your naughties router? This box filtered out the data from the telephone frequencies, helping to ensure that you can neither hear the pops and clicks of your ADSL connection nor interfere with it by shouting.

Equating the word “broadband” with speed is based on a consumer-centric misunderstanding about what broadband is, because it’s necessarily true that if your home “broadband” weren’t configured to be able to support old-fashioned telephone calls, it’d be (a) (slightly) faster, and (b) not-broadband.

The Future

But does the word that people use to refer to their high-speed Internet connection matter. More than you’d think: various countries around the world have begun to make legal definitions of the word “broadband” based not on the technical meaning but on the populist one, and it’s becoming a source of friction. In the USA, the FCC variously defines broadband as having a minimum download speed of 10Mbps or 25Mbps, among other characteristics (they seem to use the former when protecting consumer rights and the latter when reporting on penetration, and you can read into that what you will). In the UK, Ofcom‘s regulations differentiate between “decent” (yes, that’s really the word they use) and “superfast” broadband at 10Mbps and 24Mbps download speeds, respectively, while the Scottish and Welsh governments as well as the EU say it must be 30Mbps to be “superfast broadband”.

Faster, Harder, Scooter music video.
At full-tilt, going from 10Mbps to 24Mbps means taking only 4 seconds, rather than 11 seconds, to download the music video to Faster! Harder! Scooter!

I’m all in favour of regulation that protects consumers and makes it easier for them to compare products. It’s a little messy that definitions vary so widely on what different speeds mean, but that’s not the biggest problem. I don’t even mind that these agencies have all given themselves very little breathing room for the future: where do you go after “superfast”? Ultrafast (actually, that’s exactly where we go)? Megafast? Ludicrous speed?

What I mind is the redefining of a useful term to differentiate whether a connection is shared with other services or not to be tied to a completely independent characteristic of that connection. It’d have been simple for the FCC, for example, to have defined e.g. “full-speed broadband” as providing a particular bandwidth.

Verdict: It’s not a big deal; I should just chill out. I’m probably going to have to throw in the towel anyway on this one and join the masses in calling all high-speed Internet connections “broadband” and not using that word for all slower and non-Internet connections, regardless of how they’re set up.

Dan Q found GC7B8X0 Into 7th Heaven

This checkin to GC7B8X0 Into 7th Heaven reflects a geocaching.com log entry. See more of Dan's cache logs.

Wonderful location for a virtual: what a view! I’m in Cape Town for a week of work and teambuilding with my new colleagues: a rare occasion as we normally work completely remotely from many different countries. I was pleased to be able to combine work with a trip up Table Mountain, especially on such beautiful day. Snapped the attached pic, then walked over to the other side to watch the sun set. TFTC!

Dan with the Table Mountain cable car

Map of -33.957617,18.403417

Evolving Computer Words: “Virus”

This is part of a series of posts on computer terminology whose popular meaning – determined by surveying my friends – has significantly diverged from its original/technical one. Read more evolving words…

A few hundred years ago, the words “awesome” and “awful” were synonyms. From their roots, you can see why: they mean “tending to or causing awe” and “full or or characterised by awe”, respectively. Nowadays, though, they’re opposites, and it’s pretty awesome to see how our language continues to evolve. You know what’s awful, though? Computer viruses. Right?

Man staring intently at laptop. Image courtesy Oladimeji Ajegbile, via Pexels.
“Oh no! A virus has stolen all my selfies and uploaded them to a stock photos site!”

You know what I mean by a virus, right? A malicious computer program bent on causing destruction, spying on your online activity, encrypting your files and ransoming them back to you, showing you unwanted ads, etc… but hang on: that’s not right at all…

Virus

What people think it means

Malicious or unwanted computer software designed to cause trouble/commit crimes.

What it originally meant

Computer software that hides its code inside programs and, when they’re run, copies itself into other programs.

The Past

Only a hundred and thirty years ago it was still widely believed that “bad air” was the principal cause of disease. The idea that tiny germs could be the cause of infection was only just beginning to take hold. It was in this environment that the excellent scientist Ernest Hankin travelled around India studying outbreaks of disease and promoting germ theory by demonstrating that boiling water prevented cholera by killing the (newly-discovered) vibrio cholerae bacterium. But his most-important discovery was that water from a certain part of the Ganges seemed to be naturally inviable as a home for vibrio cholerae… and that boiling this water removed this superpower, allowing the special water to begin to once again culture the bacterium.

Hankin correctly theorised that there was something in that water that preyed upon vibrio cholerae; something too small to see with a microscope. In doing so, he was probably the first person to identify what we now call a bacteriophage: the most common kind of virus. Bacteriophages were briefly seen as exciting for their medical potential. But then in the 1940s antibiotics, which were seen as far more-convenient, began to be manufactured in bulk, and we stopped seriously looking at “phage therapy” (interestingly, phages are seeing a bit of a resurgence as antibiotic resistance becomes increasingly problematic).

Electron microscope image of a bacteriophage alongside an illustration of the same.
It took until the development of the scanning electron microscope in the mid-20th century before we’d actually “see” a virus.

But the important discovery kicked-off by the early observations of Hankin and others was that viruses exist. Later, researchers would discover how these viruses work1: they inject their genetic material into cells, and this injected “code” supplants the unfortunate cell’s usual processes. The cell is “reprogrammed” – sometimes after a dormant period – to churns out more of the virus, becoming a “virus factory”.

Let’s switch to computer science. Legendary mathematician John von Neumann, fresh from showing off his expertise in calculating how shaped charges should be used to build the first atomic bombs, invented the new field of cellular autonoma. Cellular autonoma are computationally-logical, independent entities that exhibit complex behaviour through their interactions, but if you’ve come across them before now it’s probably because you played Conway’s Game of Life, which made the concept popular decades after their invention. Von Neumann was very interested in how ideas from biology could be applied to computer science, and is credited with being the first person to come up with the idea of a self-replicating computer program which would write-out its own instructions to other parts of memory to be executed later: the concept of the first computer virus.

Glider factory breeder in Conway's Game of Life
This is a glider factory… factory. I remember the first time I saw this pattern, in the 1980s, and it sank in for me that cellular autonoma must logically be capable of any arbitrary level of complexity. I never built a factory-factory-factory, but I’ll bet that others have.

Retroactively-written lists of early computer viruses often identify 1971’s Creeper as the first computer virus: it was a program which, when run, moved (later copied) itself to another computer on the network and showed the message “I’m the creeper: catch me if you can”. It was swiftly followed by a similar program, Reaper, which replicated in a similar way but instead of displaying a message attempted to delete any copies of Creeper that it found. However, Creeper and Reaper weren’t described as viruses at the time and would be more-accurately termed worms nowadays: self-replicating network programs that don’t inject their code into other programs. An interesting thing to note about them, though, is that – contrary to popular conception of a “virus” – neither intended to cause any harm: Creeper‘s entire payload was a relatively-harmless message, and Reaper actually tried to do good by removing presumed-unwanted software.

Another early example that appears in so-called “virus timelines” came in 1975. ANIMAL presented as a twenty questions-style guessing game. But while the user played it would try to copy itself into another user’s directory, spreading itself (we didn’t really do directory permissions back then). Again, this wasn’t really a “virus” but would be better termed a trojan: a program which pretends to be something that it’s not.

Replica Trojan horse.
“Malware? Me? No siree… nothing here but this big executable horse.”

It took until 1983 before Fred Cooper gave us a modern definition of a computer virus, one which – ignoring usage by laypeople – stands to this day:

A program which can ‘infect’ other programs by modifying them to include a possibly evolved copy of itself… every program that gets infected may also act as a virus and thus the infection grows.

This definition helps distinguish between merely self-replicating programs like those seen before and a new, theoretical class of programs that would modify host programs such that – typically in addition to the host programs’ normal behaviour – further programs would be similarly modified. Not content with leaving this as a theoretical, Cooper wrote the first “true” computer virus to demonstrate his work (it was never released into the wild): he also managed to prove that there can be no such thing as perfect virus detection.

(Quick side-note: I’m sure we’re all on the same page about the evolution of language here, but for the love of god don’t say viri. Certainly don’t say virii. The correct plural is clearly viruses. The Latin root virus is a mass noun and so has no plural, unlike e.g. fungus/fungi, and so its adoption into a count-noun in English represents the creation of a new word which should therefore, without a precedent to the contrary, favour English pluralisation rules. A parallel would be bonus, which shares virus‘s linguistic path, word ending, and countability-in-Latin: you wouldn’t say “there were end-of-year boni for everybody in my department”, would you? No. So don’t say viri either.)

(Inaccurate) slide describing viruses as programs that damage computers or files.
No, no, no, no, no. The only wholly-accurate part of this definition is the word “program”.

Viruses came into their own as computers became standardised and commonplace and as communication between them (either by removable media or network/dial-up connections) and Cooper’s theoretical concepts became very much real. In 1986, The Virdim method brought infectious viruses to the DOS platform, opening up virus writers’ access to much of the rapidly growing business and home computer markets.

The Virdim method has two parts: (a) appending the viral code to the end of the program to be infected, and (b) injecting early into the program a call to the appended code. This exploits the typical layout of most DOS executable files and ensures that the viral code is run first, as an infected program loads, and the virus can spread rapidly through a system. The appearance of this method at a time when hard drives were uncommon and so many programs would be run from floppy disks (which could be easily passed around between users) enabled this kind of virus to spread rapidly.

For the most part, early viruses were not malicious. They usually only caused harm as a side-effect (as we’ve already seen, some – like Reaper – were intended to be not just benign but benevolent). For example, programs might run slower if they’re also busy adding viral code to other programs, or a badly-implemented virus might even cause software to crash. But it didn’t take long before viruses started to be used for malicious purposes – pranks, adware, spyware, data ransom, etc. – as well as to carry political messages or to conduct cyberwarfare.

XKCD 1180: Virus Venn Diagram
XKCD already explained all of this in far fewer words and a diagram.

The Future

Nowadays, though, viruses are becoming less-common. Wait, what?

Yup, you heard me right: new viruses aren’t being produced at remotely the same kind of rate as they were even in the 1990s. And it’s not that they’re easier for security software to catch and quarantine; if anything, they’re less-detectable as more and more different types of file are nominally “executable” on a typical computer, and widespread access to powerful cryptography has made it easier than ever for a virus to hide itself in the increasingly-sprawling binaries that litter modern computers.

"Security" button
Soo… I click this and all the viruses go away, right? Why didn’t we do this sooner?

The single biggest reason that virus writing is on the decline is, in my opinion, that writing something as complex as a a virus is longer a necessary step to illicitly getting your program onto other people’s computers2! Nowadays, it’s far easier to write a trojan (e.g. a fake Flash update, dodgy spam attachment, browser toolbar, or a viral free game) and trick people into running it… or else to write a worm that exploits some weakness in an open network interface. Or, in a recent twist, to just add your code to a popular library and let overworked software engineers include it in their projects for you. Modern operating systems make it easy to have your malware run every time they boot and it’ll quickly get lost amongst the noise of all the other (hopefully-legitimate) programs running alongside it.

In short: there’s simply no need to have your code hide itself inside somebody else’s compiled program any more. Users will run your software anyway, and you often don’t even have to work very hard to trick them into doing so.

Verdict: Let’s promote use of the word “malware” instead of “virus” for popular use. It’s more technically-accurate in the vast majority of cases, and it’s actually a more-useful term too.

1 Actually, not all viruses work this way. (Biological) viruses are, it turns out, really really complicated and we’re only just beginning to understand them. Computer viruses, though, we’ve got a solid understanding of.

2 There are other reasons, such as the increase in use of cryptographically-signed binaries, protected memory space/”execute bits”, and so on, but the trend away from traditional viruses and towards trojans for delivery of malicious payloads began long before these features became commonplace.

Dan Q found GC7B91V South with Scott

This checkin to GC7B91V South with Scott reflects a geocaching.com log entry. See more of Dan's cache logs.

Staying in the hotel nearby for a meetup event with my team, who’ve flown in from all over the world (USA, UK, France, Indonesia, Russia, among others) to meet one another face to face (we normally all work remotely). Needed to count the portholes twice but got the right answer in the end. TFTC (my first find in ZA)!

Dan with a statue at the GZ

Map of -33.919833,18.425133

Howdymattic Outtakes

Yesterday, I shared with you the introduction video I made for my new employer. A few friends commented that it seemed very well-presented and complimented me on my presentation, so I thought I’d dispel the illusion by providing this: the “outtakes”. My process was to write a loose script and then perform it multiple times (while being sure to wear the same hoodie) over the course of several days as I walked or cycled around, and then take only the “good” content.

That I’m able to effortlessly make a longer video out of a selection of the outtakes should be evidence enough that I’m just as capable of mucking-up a simple task as anybody else, probably moreso.

You may observe in this video that I made a number of “Hey, I found a…” snippets; I wasn’t sure what would scan best (I eventually went with “Hey, I found a… nothing?”). Folks who’ve seen this video have already criticised my choice; apparently the cow I found was more photogenic than me.

Also available on: VideoPress, QTube, YouTube.