networking

Icebreakers – Heraldry and Compairs

I’m in Amsterdam for a meetup for my new team at Automattic.

When we’ve not been out tackling escape rooms, finding geocaches, and eating curry, we’ve been doing a variety of activities to help solidify our new team’s goals, priorities, and expertise: y’know, the normal things you might expect on a company away week.

I volunteered to lead the initial session on our first day with a couple of icebreaker games, which went well enough that I’m inclined to share them here in case they’re of any use to you. The games we played are called Heraldry and Compairs. Let’s take a look:

Heraldry

I was looking at the coat of arms of Noord Holland, the province in which Amsterdam lies, and thinking about all the symbolism and propaganda that’s encoded into traditional heraldry, and how much effort it takes to decode it… unless you just, y’know, guess!

Per pale or and azure; I a lion rampant gules, armed and langued azure, II seme of horizontally placed billets or, two lions passant guardant in pale of the same. The shield is crested by a coronet of five leaves or. ²

I asked each participant to divide a shield into five quadrants and draw their own coats of arms, featuring aspects of (a) their work life, (b) their personal life, (c) something they value, (d) something they’re good at, and (e) something surprising or unusual. I really wanted to keep the time pressure on and not allow anybody to overthink things, so I set a 5-minute timer from the moment everybody had finished drawing their shield outline.

Then, everybody passed their drawing to the right, and each person in turn tried, as best they could, to introduce the person to their left by attempting to interpret their neighbour’s drawing. The known categories helped to make it easier by helping people latch onto something to start talking about, but also more-challenging as people second-guessed themselves (“no, wait, maybe it’s sailing you’re good at and guitar you play in your personal life?”).

Six hand-drawn sketches of heraldic coats of arms by six different Automatticians. Ballpoint pen on paper. — This wasn’t about artistic skills; it was about getting people to talk to one another. Which is for the best, given my (lack of) artistic skills.

After each introduction is made, the person being introduced gets to explain their heraldry for themselves, congratulating their introducer on the things they got right and their close-guesses along the way.

It’s sort-of halfway between “introduce your neighbour” and “pictionary”. And it worked well to get us warmed-up, feeling a little silly, knowing one another slightly better, and in a space in which everybody had been expected to have spoken and to have made a harmless mistake (everybody managed to partially-interpret a shield correctly). A useful place to be at the end of an icebreaker exercise is left with the reminder that we are, after all, only human.

Compairs

Next up, we played a game only slightly inspired by witnessing a game of Mr and Mrs the other week³. I threw together a Perchance (which, in the nature of such things, is entirely open-source and you’re welcome to adapt it for your own use) that generated a series of randomly-selected pairs of teammates and asked a question to differentiate the two of them.

Screenshot of the game asking: "Gareth vs Dan (Travel category): Who's taken the longest boat ride?" — Some of the questions were gentle, but solicited a reasonable amount of guesswork alongside a modest amount of deduction.

Participants other than the two shown on the screen were challenged to guess the answer to the question. Sometimes the questions would have a definitive answer, and sometimes not: the joy was in the speculation! “Hmm, I know that Dan’s done quite a bit of globetrotting… but could he actually have travelled further East than a colleague who lives much further East than him?”

After a few seconds to a minute, once their colleagues had settled on an answer, the people listed on the question were encouraged to make their own guesses. Usually they’ll have a better idea as they are one of the data points, but that’s not always true!

Screenshot of the game asking: "Michal vs Raja (Code category): I can't remember whether I need aria-label or aria-labelledby. Who can tell me?" — A handful of questions were even tangentially work-related. Who is the accessibility Web expert in our team, anyway?

There’s no points, and you can play for as long as you like so long as it’s long enough that everybody gets at least one turn, so it’s a good “fill the rest of the time slot” game. It follows Heraldry moderately well as an icebreaker double-feature because the former is firstly about learning things about one another (and to a lesser extent guessing), and the latter is about the opposite.

I came out of both games knowing more about the humans behind the screens in my new team, and it seemed to open up the room for some good discussions afterwards, so the social lubricant effect was clearly effective too. If you give them a go or adapt them into anything else, let me know!

Footnotes

¹ Our absent colleague instead had to tower over us on an enormous projector screen.

² The red (“gules”) upright (“rampant”) lion in the coat of arms possibly comes from the heraldry of the city of Gelderen in Germany, but once part of the Dutch Republic. The lions striding (“passant”) to the left (“to dexter”) but turning to face you (“guardant”) come from the arms of Fryslân (Friesland), and its rectangles represent the districts of Fryslân. Aren’t you glad you asked.

³ Also known as The Newlyweds Game after the US game show of that name and basically the same format, Mr and Mrs is a game in which a (typically newly) married couple are asked questions about one another and their lives together which they answer separately and then those answers are compared. This induces a reaction of compersion when they’re “right” and in-sync and when the couple disagree it results in amusement. Or possibly divorce.

From Synergy to Barrier

I’ve been using Synergy for a long, long time. By the time I wrote about my admiration of its notification icon back in 2010 I’d already been using it for some years. But this long love affair ended this week when I made the switch to its competitor, Barrier.

Screenshot showing some pre-1.3 version of Synergy running on Windows Vista. — I’m not certain exactly when I took this screenshot (which I shared with Kit while praising Synergy), but it’s clearly a pre-1.4 version and those look distinctly like Windows Vista’s ugly rounded corners, so I’m thinking no later than 2009?

If you’ve not come across it before: Synergy was possibly the first multiplatform tool to provide seamless “edge-to-edge” sharing of a keyboard and mouse between multiple computers. Right now, for example, I’m sitting in front of Cornet, a Debian 11 desktop, Idiophone, a Macbook Pro docked to a desktop monitor, and Renegade, a Windows desktop. And I can move my mouse cursor from one, to the other, to the next, interacting with them all as if I were connected directly to it.

There have long been similar technologies. KVM switches can do this, as can some modern wireless mice (I own at least two such mice!). But none of them are as seamless as what Synergy does: moving from computer to computer as fast as you can move your mouse and sharing a clipboard between multiple devices. I also love that I can configure my set-up around how I work, e.g. when I undock my Macbook it switches from ethernet to wifi, this gets detected and it’s automatically removed from the cluster. So when I pick up my laptop, it magically stops being controlled by my Windows PC’s mouse and keyboard until I dock it again.

Synergy’s published under a hybrid model: open-source components, with paid-for extra features. It used to provide more in the open-source offering: you could download a fully-working copy of the software and use it without limitation, losing out only on a handful of features that for many users were unnecessary. Nontheless, early on I wanted to support the development of this tool that I used so much, and so I donated money towards funding its development. In exchange, I gained access to Synergy Premium, and then when their business model changed I got grandfathered-in to a lifetime subscription to Synergy Pro.

I continued using Synergy all the while. When their problem-stricken 2.x branch went into beta, I was among the testers: despite the stability issues and limitations, I loved the fact that I could have what was functionally multiple co-equal “host” computers, and – when it worked – I liked the slick new configuration interface it sported. I’ve been following with bated breath announcements about the next generation – Synergy 3 – and I’ve registered as an alpha tester for when the time comes.

If it sounds like I’m a fanboy… that’d probably be an accurate assessment of the situation. So why, after all these years, have I jumped ship?

Email from Symless to Dan, reading: "Thank you for contacting Synergy Support. My name is Kim and I am happy to assist you. We do not have a download option for the 32 bit version of Debian 10. We currently only have the options available in the members area. Feel free to reach out if you have any further questions or concerns." — Dear Future Dan. If you ever need a practical example of where open-source thinking provides a better user experience than arbritrarily closed-source products, please see above. Yours, Past Dan.

I’ve been aware of Barrier since the project started, as a fork of the last open-source version of the core Synergy program. Initially, I didn’t consider Barrier to be a suitable alternative for me, because it lacked features I cared about that were only available in the premium version of Synergy. As time went on and these features were implemented, I continued to stick with Synergy and didn’t bother to try out Barrier… mostly out of inertia: Synergy worked fine, and the only thing Barrier seemed to offer would be a simpler set-up (because I wouldn’t need to insert my registration details!).

This week, though, as part of a side project, I needed to add an extra computer to my cluster. For reasons that are boring and irrelevant and so I’ll spare you the details, the new computer’s running the 32-bit version of Debian 11.

I went to the Symless download pages and discovered… there isn’t a Debian 11 package. Ah well, I think: the Debian 10 one can probably be made to work. But then I discover… there’s only a 64-bit version of the Debian 10 binary. I’ll note that this isn’t a fundamental limitation – there are 32-bit versions of Synergy available for Windows and for ARMhf Raspberry Pi devices – but a decision by the developers not to support that platform. In order to protect their business model, Synergy is only available as closed-source binaries, and that means that it’s only available for the platforms for which the developers choose to make it available.

So I thought: well, I’ll try Barrier then. Now’s as good a time as any.

Barrier and Synergy aren’t cross-compatible, so first I had to disable Synergy on each machine in my cluster. Then I installed Barrier. Like most popular open-source software, this was trivially easy compared to Synergy: I just used an appropriate package manager by running choco install barrier, brew install barrier, and apt install barrier to install on each of the Windows, Mac, and Debian computers, respectively.

Configuring Barrier was basically identical to configuring Synergy: set up the machine names, nominate one the server, and tell the server what the relative positions are of each of the others’ screens. I usually bind the “scroll lock” key to the “lock my cursor to the current screen” function but I wasn’t permitted to do this in Barrier for some reason, so I remapped my scroll lock key to some random high unicode character and bound that instead.

Getting Barrier to auto-run on MacOS was a little bit of a drag – in the end I had to use Automator to set up a shortcut that ran it and loaded the configuration, and set that to run on login. These little touches are mostly solved in Synergy, but given its technical audience I don’t imagine that anybody is hugely inconvenienced by them. Nonetheless, Synergy clearly retains a slightly more-polished experience.

Altogether, switching from Synergy to Barrier took me under 15 minutes and has so far offered me a functionally-identical experience, except that it works on more devices, can be installed via my favourite package managers, and doesn’t ask me for registration details before it functions. Synergy 3’s going to have to be a big leap forward to beat that!

Syncthing

This last month or so, my digital life has been dramatically improved by Syncthing. So much so that I want to tell you about it.

I started using it last month. Basically, what it does is keeps a pair of directories on remote systems “in sync” with one another. So far, it’s like your favourite cloud storage service, albeit self-hosted and much-more customisable. But it’s got a handful of killer features that make it nothing short of a dream to work with:

The unique identifier for a computer can be derived from its public key. Encryption comes free as part of the verification of a computer’s identity.
You can share any number of folders with any number of other computers, point-to-point or via an intermediate proxy, and it “just works”.
It’s super transparent: you can always see what it’s up to, you can tweak the configuration to match your priorities, and it’s open source so you can look at the engine if you like.

Here are some of the ways I’m using it:

Keeping my phone camera synced to my PC

I’ve tried a lot of different solutions for this over the years. Back in the way-back-when, like everybody else in those dark times, I used to plug my phone in using a cable to copy pictures off and sort them. Since then, I’ve tried cloud solutions from Google, Amazon, and Flickr and never found any that really “worked” for me. Their web interfaces and apps tend to be equally terrible for organising or downloading files, and I’m rarely able to simply drag-and-drop images from them into a blog post like I can from Explorer/Finder/etc.

At first, I set this up as a one-way sync, “pushing” photos and videos from my phone to my desktop PC whenever I was on an unmetered WiFi network. But then I switched it to a two-way sync, enabling me to more-easily tidy up my phone of old photos too, by just dragging them from the folder that’s synced with my phone to my regular picture storage.

Centralising my backups

Now I’ve got a fancy NAS device with tonnes of storage, it makes sense to use it as a central point for backups to run fom. Instead of having many separate backup processes running on different computers, I can just have each of them sync to the NAS, and the NAS can back everything up. Computers don’t need to be “on” at a particular time because the NAS runs all the time, so backups can use the Internet connection when it’s quietest. And in the event of a hardware failure, there’s an up-to-date on-site backup in the first instance: the cloud backup’s only needed in the event of accidental data deletion (which could be sync’ed already, of course!). Plus, integrating the sync with ownCloud running on the NAS gives easy access to my files wherever in the world I am without having to fire up a VPN or otherwise remote-in to my house.

Plus: because Syncthing can share a folder between any number of devices, the same sharing mechanism that puts my phone’s photos onto my main desktop can simultaneously be pushing them to the NAS, providing redundant connections. And it was a doddle to set up.

Maintaining my media centre’s screensaver

Since the NAS, running Jellyfin, took on most of the media management jobs previously shared between desktop computers and the media centre computer, the household media centre’s had less to do. But one thing that it does, and that gets neglected, is showing a screensaver of family photos (when it’s not being used for anything else). Historically, we’ve maintained the photos in that collection via a shared network folder, but then you’ve got credential management and firewall issues to deal with, not to mention different file naming conventions by different people (and their devices).

But simply sharing the screensaver’s photo folder with the computer of anybody who wants to contribute photos means that it’s as easy as copying the picture to a particular place. It works on whatever device they care to (computer, tablet, mobile) on any operating system, and it’s quick and seamless. I’m just using it myself, for now, but I’ll be offering it to the rest of the family soon. It’s a trivial use-case, but once you’ve got it installed it just makes sense.

In short: this month, I’m in love with Syncthing. And maybe you should be, too.

Fox (Household NAS)

Last week I built Fox, the newest addition to our home network. Fox, whose specification called for not one, not two, not three but four 12 terabyte hard disk drives was built principally as a souped-up NAS device – a central place for us all to safely hold and control access to important files rather than having them spread across our various devices – but she’s got a lot more going on that that, too.

A black computer "cube" nestled under a desk, amongst cables. — Right now, Fox lives under my desk along with most of our network cables.

Fox has:

Enough hard drive space to give us 36TB of storage capacity plus 12TB of parity, allowing any one of the drives to fail without losing any data.
“Headroom” sufficient to double its capacity in the future without significant effort.
A mediumweight graphics card to assist with real-time transcoding, helping her to convert and stream audio and videos to our devices in whatever format they prefer.
A beefy processor and sufficient RAM to run a dozen virtual machines supporting a variety of functions like software development, media ripping and cataloguing, photo rescaling, reverse-proxying, and document scanning (a planned future purpose for Fox is to have a network-enabled scanner near our “in-trays” so that we can digitise and OCR all of our post and paperwork into a searchable, accessible, space-saving collection).

QFlix (media selection) menu showing on a TV — “QFlix” is a lot like Netflix, except geared mostly towards saving us from having to walk over to the DVD shelf or remember which disc we were up to when watching a long-running series. #firstworldproblems

The last time I filmed myself building a PC was when I built Cosmo, a couple of desktops ago. He turned out to be a bit of a nightmare: he was my first fully-watercooled computer and he leaked everywhere: by the time I’d done all the fixing and re-fixing to make him behave nicely, I wasn’t happy with the video footage and I never uploaded it. I’d been wary, almost-superstitious, about filming a build since then, but I shot a timelapse of Fox’s construction and it turned out pretty well: you can watch it below or on YouTube or QTube.

The timelapse slows to real-time, about a minute in, to illustrate a point about the component test I did with only a CPU (and cooler), PSU, and RAM attached. Something I routinely do when building computers but which I only recently discovered isn’t commonly practised is shown: that the easiest way to power on a computer without attaching a power switch is just to bridge the power switch pins using your screwdriver!

Fox is running Unraid, an operating system basically designed for exactly these kinds of purposes. I’ve been super-impressed by the ease-of-use and versatility of Unraid and I’d recommend it if you’ve got a similar NAS project in your future! I’d also like to sing the praises of the Fractal Design Node 804 case: it’s not got quite as many bells-and-whistles as some cases, but its dual-chamber design is spot-on for a multipurpose NAS, giving ample room for both full-sized expansion cards and heatsinks and lots of hard drives in a relatively compact space.

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.

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.

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.

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”.

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.

Note #15043

My hardware engineering is a little rusty, @ComputerHistory, but wouldn’t signals propogate along this copper cable at “only” somewhere between 0.64c and 0.95c, not 1c as you claim?

The network is reliable

This is a repost promoting content originally published elsewhere. See more things Dan's reposted.

In the spring of that year, my travels brought me upon a previously undiscovered civilization. The people called themselves Ossians, and they lived in an isolated collection of villages in a remote part of South America.

Being remote as they were, their level of technology was understandably primitive. But I was surprised by the locals’ recent obsession with new forms of communication. It all started, they told me, when one of them discovered that by attaching a rope between two clay pots and stretching the rope taut, a voice uttered into one side could be heard on the other. (I neglected to tell them that even as a boy I had done this very thing with tin cans.)…

David Boike (Particular Software)

New Computer #2 – Dana

The other week I built Tiffany2, New Earth‘s new media centre computer. She’s well-established and being used to watch movies, surf the web, and whatnot, now, so I thought I’d better fulfil my promise of telling you about my other new smaller-than-average computer, Dana, whose existence was made possible by gifts from my family over Christmas and my birthday.

Dana‘s size and power-consumption is so small that it makes Tiffany2 look like a bloated monster. That’s because Dana is a DreamPlug, an open-architecture plug computer following in the footsteps of the coveted SheevaPlug and GuruPlug.

The entire computer including its detachable power supply is only a little larger than the mobile telephones of the mid-nineties, and the entire device can be plugged straight into the wall. With no hard disk (it uses SD cards) and no fans, the DreamPlug has no moving parts to wear out or make noise, and so it’s completely silent. It’s also incredibly low-power – mine idles at about 4 watts – that’s about the same as a radio alarm clock, and about a hundredth of what my desktop PCs Toni and Nena run at under a typical load.

I’ve fitted up mine with a Mimo Mini-Monster 10″: a dinky little self-powered USB-driven touchscreen monitor about the size of an iPad. Right now the whole assembly – about the size of a large picture frame – sits neatly in the corner of my desk and (thanks to the magic of Synergy) forms part of my extended multi-monitor desktop, as well as acting as a computer in her own right.

So on the surface, she’s a little bit like a wired tablet computer, which would seem a little silly (and indeed: at a glance you’d mistake her for a digital photo frame)! But because she’s a “real” computer underneath, with a 1.2GHz processor, 512MB RAM, USB, WiFi, and two Ethernet ports, there’s all kinds of fun things that can be done with her.

For a start, she provides an ultra low-power extension to my existing office development environment. I’ve experimented with “pushing” a few tasks over to her, like watching log file output, downloading torrents, running a web server, reading RSS feeds, and so on, but my favourite of her tasks is acting as a gateway between the rest of the world and my office.

While they’ve come a long way, modern ADSL routers are still woefully inadequate at providing genuine customisability and control over my home network. But a computer like this – small, silent, and cheap – makes it possible to use your favourite open-source tools (iptables, squid, sshd, etc.) as a firewall to segregate off a part of the network. And that’s exactly what I’ve done. My office – the pile of computers in the upper-right of the diagram, above – is regulated by Dana, whose low footprint means that I don’t feel bad about leaving her turned always-on.

That means that, from anywhere in the world (and even from my phone), I can now:

Connect into Dana using SSH.
Send magic packets to Toni, Nena, or Tiffany2 (all of which are on wired connections), causing them to turn themselves on.
Remotely control those computers to, for example, get access to my files from anywhere, set them off downloading something I’ll need later, or whatever else.
Turn them off when I’m done.

That’s kinda sexy. There’s nothing new about it – the technologies and standards involved are as old as the hills – but it’s nice to be able to do it using something that’s barely bigger than a postcard.

I have all kinds of ideas for future projects with Dana. It’s a bit like having a souped-up (and only a little bigger) Arduino to play with, and it’s brimming with potential. How about a webcam for my bird feeder? Or home-automation tools (y’know: so I can turn on my bedroom light without having to get out of bed)? Or a media and file server (if I attached a nice, large, external hard disk)? And then there’s the more far-fetched ideas: it’s easily low-power enough to run from a car battery – how about in-car entertainment? Or home-grown GPS guidance? What about a “delivered ready-to-use” intranet application, as I was discussing the other day with a colleague, that can be simply posted to a client, plugged in, and used? There’s all kinds of fun potential ideas for a box like this, and I’m just beginning to dig into them.

New Computer #1 – Tiffany2

This weekend, I integrated two new computers into the home network on New Earth. The first of these is Tiffany2.

Tiffany2 replaces Tiffany, the media centre computer I built a little under four years ago. The original Tiffany was built on a shoestring budget of under £300, and provided the technical magic behind the last hundred or so Troma Nights, as well as countless other film and television nights, a means to watch (and record and pause) live TV, surf the web, and play a game once in a while.

The problem with Tiffany is that she was built dirt-cheap at a time when building a proper media centre PC was still quite expensive. So she wasn’t very good. Honestly, I’m amazed that she lasted as long as she did. And she’s still running: but she “feels” slow (and takes far too long to warm up) and she makes a noise like a jet engine… which isn’t what you want when you’re paying attention to the important dialogue of a quiet scene.

Tiffany2 is virtually silent and significantly more-powerful than her predecessor. She’s also a lot smaller – not much bigger than a DVD player – and generally more feature-rich.

This was the first time I’d built an ITX form-factor computer (Tiffany2 is Mini-ITX): I wanted to make her small, and it seemed like the best standard for the job. Assembling some of her components felt a little like playing with a doll’s house – she has a 2.5″ hard disk and a “slimline” optical drive: components that in the old days we used to call “laptop” parts, which see new life in small desktop computers.

In order to screw in some of the smaller components, I had to dig out my set of watchmaker’s screwdrivers. Everything packs very neatly into a very small space, and – building her – I found myself remembering my summer job long ago at DesignPlan Lighting, where I’d have to tuck dozens of little components, carefully wired-together, into the shell of what would eventually become a striplight in a tube train or a prison, or something.

She’s already deployed in our living room, and we’ve christened her with the latest Zero Punctuation, a few DVDs, some episodes of Xena: Warrior Princess, and an episode of Total Wipeout featuring JTA‘s old history teacher as a contestant. Looks like she’s made herself at home.

(for those who are sad enough to care, Tiffany2 is running an Intel Core i3-2100 processor, underclocked to 3GHz, on an mITX Gigabyte GA-H61N-USB3 motherboard with 4GB RAM, a 750GB hard disk, and DVD-rewriter, all wrapped up in an Antec ISK 300-150 case with a 150W power supply: easily enough for a media centre box plus some heavy lifting if I ever feel the need to give her any)

A Small World Conspiracy

I keep getting caught up on small world coincidences, since I started working at the Bodleian Library last week. I know about selective biases, of course, and I’ve always said that coincidences happen nine times out of ten, but this is really starting to feel like some kind of amazing conspiracy that I’ve somehow wandered into.

The most recent chain of connected coincidences is also probably the most impressive. But to explain it, I’ll need to take you back in time by almost three years. Back in the summer of 2008, I went to BiCon for the second time, accompanied by Claire and Matt P. Among the various other things we got up to, we met a young lady called Ann (who, if I remember rightly, got along very well with Matt).

This morning I received an email from Ann. It turns out that she works in the Bodleian Libraries: she’s likely to be one of the very users who it’s now my job to provide training and technical support to! She saw my photograph in the newsletter I mentioned in my last blog post and looked me up: small world! I emailed back, suggesting that we get together for a drink after work, and she agreed: great! She also asked if she could bring a friend along, a colleague from the library. Sure, I said, sounds good.

This lunchtime I sorted out some of my holiday entitlement for the rest of this academic year. I booked off a few days for a Three Rings “code week” in the summer, and a couple of days around the time that I’ll be moving house next month. One of these days clashed with a meeting that I’d had planned with the Web/Digital Officer of one of the libraries (I’m doing a grand tour of many of the libraries that comprise the Bodleian, in order to meet all the relevant people), so I sent an email to this staff member to ask if we could reschedule our meeting to another time.

“Okay,” they said, “But I think I’m meeting you in the pub in 90 minutes anyway…”

It turns out that the person whose meeting I’ve asked to reschedule is the friend of the person who recognised me from the staff newsletter, having originally met me three years ago. Out of all of the people (I’m not sure how many exactly – it’s probably in the staff handbook I haven’t read yet – but I’ll bet it’s a lot) that are employed by this, the largest university library in the UK, what are the odds?

Fibre Optics Are Cool

See:

This is how I like my downloads to look.

Lord Fear’s Copy Of ZoneAlarm

How To Use SSH Tunnelling To Allow Services To Pass Through A Firewall

[this post has been partially damaged during a server failure on 11 July 2004; with the exception of the images, it was recovered on 13 October 2018]

Paul has been stuck with a problem of late – he’s now living in university accomodation, and he’s found that he can’t connect through the university firewall to his external mail server. I advised him that it’s possible to set up an ‘SSH Tunnel’ (through central.aber.ac.uk) to fix this problem, but he hasn’t met with much success (see his blog entry for more details). In any case, here’s my investigation (and solution) to the problem.

How To Use SSH Tunnelling To Allow Services To Pass Through A Firewall
In my example, I’m going to try the opposite to what Paul is trying to achieve. I’m going to try to allow my POP3 e-mail client to get access to the university e-mail server (pophost.aber.ac.uk). As things stand, this server is on the other side of the university firewall, and is inaccessible from outside. The server central.aber.ac.uk, however, is accessible from both sides of the firewall. So what I’ve got is this (yes, I know that this is a gross oversimplification):

As you can see, connecting from my home PC is futile:

C:\Documents and Settings\Dan>telnet pophost.aber.ac.uk 110 Connecting To pophost.aber.ac.uk...Could not open connection to the host, on por t 110: Connect failed

But if I SSH-in to central.aber.ac.uk…

central:~ $ telnet pophost.aber.ac.uk 110 Trying 144.124.16.40... Connected to pophost.aber.ac.uk. Escape character is '^]'. +OK mailsplit Oct 2000 ready

So, what I need to do is to tell my SSH client to connect to central.aber.ac.uk, and forward specific traffic through the firewall to the mail server. Here’s what I needed to know:

(a) A free TCP port number on my own computer from which I can virtually ‘pipe’ the connection. Most numbers over 1024 are fine. I chose ‘9110’.
(b) The name of the mail server – ‘pophost.aber.ac.uk’.
(c) The TCP port to which I wanted to connect – the standard port for a POP3 mail server is ‘110’.
(d) My user name on a server which: (1) I can connect to; (2) can connect to the server specified in (b). It happens to be ‘dlh9’.
(e) The name of the server specified in (d) (i.e. ‘central.aber.ac.uk’).
(f) My password on the server. Like I’m going to tell you that.

The syntax is:

ssh -L (a):(b):(c) (d)@(e)

I’m using the non-commercial version of SSH Secure Shell Client, so here’s what happens:

C:\Documents and Settings\Dan>"\Program Files\SSH Secure Shell\ssh2.exe" -L 9110 :pophost.aber.ac.uk:110 dlh9@central.aber.ac.uk dlh9's password: Authentication successful.

At this point, I’m ready to go. Look what happens when I connect to port 9110 on my own computer, now…

C:\Documents and Settings\Dan>telnet localhost 9110 +OK mailsplit Oct 2000 ready

I could simply point my e-mail program at the ‘mail server’ at localhost:9110, and I’d be able to collect my university e-mail (so long as my SSH connection remained open).

Hopefully this guide will help some folks out there who are struggling with this kind of thing, and in particular, help Paul.

LORD II – Preston College Version

This document was shared on my college Intranet and via a hidden URL on my first website, on 11 December 1997. It was republished here on 22 March 2021. It provides instructions for players of the multiplayer DOOR game I adapted for local network play and the world I built within it for my friends to explore. The game world was an adaptation of our very own Preston College but transplanted to a fantasy realm.

LEGEND OF THE RED DRAGON II – Preston College Version

You have probably been given this sheet because you have requested a chance to take part in one of the most fast-moving and user-interactive multi user games on earth. I’ve spent a lot of time recently reprogramming Seth Able Robinson’s Bulletin Board System game, Legend Of The Red Dragon II (with his permission) to customise it and make it suitable for network play.

But – I’m sure this waffle is worthless to you; so here are the instructions you need:

To run the software:

Drop to an MS-DOS shell using the appropriate icon. Change to the ALEVEL.001 directory, if you’re not already there, by typing CD\ALEVEL.001. Type PC (abbreviation of Preston College) to start. You will be asked for your user name and password. These should be on a slip of paper attached to the foot of this sheet. Your password will be hidden from view for security.

Upon logging in for the first time you will see a menu from which you can choose to see the instructions, and other functions, or start the game. It is recommended that you read the instructions now, though do remember it is possible to get to them from the game by tapping ?.

Assuming you’ve discovered how to play, by one means or another, here is a list of some people and places in the game you might want to visit.

(Please note : The map of Preston College in the game is only representative, and not necessarily accurate. There is most definitely not a cult temple or a stone circle on campus…)

ENROLMENT

Until you have visited here you won’t have a membership card, which allows you access to much of the game. It’s one of the first places your character should visit.

STUDENT SERVICES

Right next door to enrolment, this cool office will buy junk that you don’t want any more from you.

THE BEASTMAN

Kevin Geldard, your computing teacher, lives in an office on the Ground Floor of the Main Building. Though he can be prone to rambling on and persistently saying “BEAST!” in the middle of otherwise sane-sounding sentences, he’s the key to a lot of the game world, and a valuable resource.

NETWORK SERVER

Found within the I.T. Block, this machine is the hub of all the computers in the college. With it it’s possible to really screw up somebody’s student record. However, it’s kept under lock and key.

VENDING MACHINES

Keep your eye out for these, as you can buy food and drinks from them. Different foodstuffs restore different quantities of Hit Points, so try them all (remember that some also have extra purposes beyond the obvious…)

MESSAGE BOARDS

Scattered around the college, these appear as a coloured section of wall. You can write messages on them to other players, to arrange trade, combat and other meetings.

SOUTHERN PATH AND SAVICK BROOK

This dirt path, found beyond the amphitheatre, is a dangerous land. Head to it to practice your combat skills, and earn a little money and experience while you’re at it. The brook is a barrier, protecting the campus from the Lands Of Chaos beyond. It is possible to cross the river at the bridge, but only the greatest warriors are allowed across.

TEMPLE OF NIG

The Disciples of Nig, a religious cult, have established themselves within the campus. Finding their temple will enable you to meditate there. Check the daily College Bulletin (by pressing D) to find out if the Disciples are celebrating a festival to determine if it is worth your while to go there.

STONE CIRCLE

It is believed that the black altar within this strange circle of standing stones is blessed with a power beyond that of this world.

REFECTORY

This safe haven is a land of protection from other players. Take refuge here to escape the blows of your enemies. Just remember that you need your Student ID Card to get in.

NESCAFE BAR

The place to hang out if you’re waiting for somebody. Right next to a message board, and with easy access to the main doors, you can settle down here if you don’t quite require the level of security the refectory provides.