How Bitcoin Works

December 4th, 2013

Fascinating and more than a bit clever, if you’ll excuse the pun.

No signal

October 27th, 2013

I’m writing this in the notes app on my phone because I’ve got no signal so cannot log into my blog, or download and set up the WordPress app (which itself wouldn’t be able to connect to my blog anyway, and I can’t remember whether it works offline). Actually, worse than having no signal, I’ve got a patchy 2 bars and a GPRS connection that occasionally steps up to Edge but then drops out completely and the process starts over again. The tease.

I’m at my in-laws’ house and they don’t “have the Internet” here, and actually don’t particularly want it either. Oddly there are no neighbours’ WiFi networks in range; I just tried in the hope of finding a BT Openzone (or Fon) I could latch onto. Nope. Not even any private ones. A luddite neighbourhood?

I remember (of course) not having the Internet. Other than games, in those days PCs were more or less devoid of distractions. The 1996 equivalent of scrolling through Vines for 10 minutes was playing a game of Minesweeper on the big setting.

I remember my dad having Compuserve, and it seeming a bit boring. Then, later, I remember picking up a Freeserve disc from Dixons in Stockport and being fairly excited about getting on the World Wide Web – but not being exactly sure what the web was or whether I’d be that into it. I think I assumed it’d be a novelty for a while – I liked the idea of email – but had no idea quite how big a deal it would turn out to be. “Quite”, you might say.

By 1997 I had made my own website complete, of course, with a visible hit counter and a Java plugin ripple effect. The future.

At university in 1998 we had an internet connection at our student house in Leeds but only on one of our PCs at a time, depending on which room we ran the phone extension and modem to. “Are you going to be long on the Web? Can you give me a shout when you’re finished so I can use the phone?”

We played 2-player Warcraft II and Starcraft between the bedrooms on floors 2 and 3 by way of daisy-chaining parallel printer cables (remember LPT1?) and putting a Laplink cable on one end to reverse the gender and pin-out. I always lost.

And Unreal Tournament through a 56k ‘v90’ was unseen assailant frag hell. Though it’s impressive that it was playable at all.

None of this was that long ago. It’s remarkable how quickly we’ve come to expect connectivity to the Internet, wirelessly everywhere, such that now (trips into the wilderness aside) being offline is the exception rather than the norm.

The Internet has become a kind of magical Higgs-Field-like property that pervades the very air we breathe… Until we lose signal and the spell is broken.

“Oh for God’s sake, why won’t it just load?!”

So, keeping in mind that famous Louis C.K. clip, I won’t complain. That such a thing as a wireless Internet connection exists at all is little short of a miracle (well that and the culmination of decades of work by scientists, mathematicians and engineers).

Instead I’ll write this offline on my phone to kill some time until I’m tired enough to fall asleep. Which is, conveniently, now.

Moved this blog

March 10th, 2013

Click away now if you’re not interested in web servers.

Having spent much of the last few years making sure clients’ websites are fast and responsive, I finally got round to sorting my own blog out. It was letting the side down, being quite sluggish and unoptimised in its shared hosing environment. So I’ve moved this over to my own server which is running Varnish, nginx and also PHP 5.4 with APC.

WordPress, which this blog runs on, works out of the box in Apache + PHP environments but getting it running in nginx (with PHP-FPM) was a bit of a pain in the arse. This is mostly because .htaccess files are an Apache thing so don’t work in nginx. nginx has its own syntax for setting up redirects and there are tools out there for converting between the two but none of the ones I found converted my existing rules successfully.

Frustratingly, following these official instructions to the letter did not work either. Getting the main WordPress installation working was fine but the problem was WP Super cache which relies on some specific rewriting logic. Certain valid post URLs were throwing up 404 errors depending on the state of the cache and what characters were in the address. At that point it had reached 1am so I decided as an interim to put Apache on the server too. I’ll return to the nginx configuration sometime soon. I have other sites running off this server through nginx, it’s just that WordPress-plugin-specific problem that needs solving.

Running Varnish on the server means it’s now easy to route traffic to either Apache or nginx as required based on the request hostname and of course it caches the returned documents so speeds things up even more. Ideally I’d have assets going to a CDN but given that I only get a handful of visitors each day it doesn’t really seem worth the effort.

Anyway, that’s it for dev-ops news. Hopefully this blog will be a bit more responsive from now on.


P.S. OK, so signing in to leave comments is currently broken. This is due to my Varnish configuration. I need to make exceptions for cookies. I’m sure you’ll manage in the meantime. <-- Now fixed

Bitcasa having teething troubles?

February 22nd, 2013

*See update at the end of this post*

Bitcasa_Logo

Having read several favourable reviews I signed up for a Bitcasa account yesterday. The desktop app for OS X looks good and works well. The user-experience is not entirely dissimilar to Dropbox in that you have a special folder which is then synchronised to their cloud storage. However the the Bitcasa drive is a mounted network drive, so doesn’t take up space on your hard disk, whereas the Dropbox folder is local.

bitcasa-infinite-drive

“Infinite storage” sounded appealing and they’re running a $69.99 offer for a year, so I went for it.

However… I’m now finding it incredibly slow to upload files. Speedtest.net tells me the upload bandwidth of my internet connection is 13Mbps, or ~1.88 MB/s. Bitcasa (mirroring a folder through the app) is just about sustaining 190KB/s which means it’s using only around 1/10th of my available bandwidth.

Dropbox by comparison on the same machine and connection manages around 750KB/s, which is about 4 times as fast.

I’ve tried to get some help from them but at the moment it’s like talking to a brick wall. 24 hours on they’ve still failed to respond to two support tickets I raised, nor have they replied to my nudge on Twitter. And there are at least a couple of threads in their community forum filling up with comments from what sound like extremely dissatisfied customers – such as this one.

I hope it’s just teething trouble and they sort this out, but the apparent stony silence from the company doesn’t bode well to me. As one forum user commented (here):

“The bottom line is it came out of beta too early and we’re paying the price now.”

Surely the first and most important thing to do is talk to their new paying customers. When people part with their cash they want service!


Update – 23 Feb

Last night I received a reply from Bitcasa on Twitter:

Also, they’ve responded to my ticket and have commented (and apologised) in a number of the forum threads, such as this one:

“We definitely are inundated with tickets, and are working very hard to respond to everyone as quickly as we can, in order to best address everyone’s help needs.”

It sounds as though they’ve had a huge influx of users and that’s taking its toll on both customer support and the system itself. Plus there are seemingly a few bugs in the software that need ironing out. From their explanations, due to their protocol the data transfer rate is affected by the ping time to the server. They’re using Amazon Web Services so are currently restricted to US, Japan and Ireland data centres.

Being in the UK I’m getting a ~30ms ping time to eu1.api.bitcasa.com, which is pretty good, and my Bitcasa upload speed seems to have vastly improved overnight without me having changed anything. I’m now getting around 800KB/sec according to their app, which is not too bad. I hope it stays that way.

I’m sure they will get things sorted out but, as ever, customer support is key. If things are going wrong 24 hours without a response can feel like a long time for a paying customer. Even to acknowledge that there’s a problem and to say “we’re working on it” goes a long way in these situations.

20130124-074820.jpg

The clock in the station I commute from each morning was for a few weeks displaying the wrong time. I think it was about five minutes fast. And then they stuck a handwritten Out Of Order notice over it, which remained for a further two weeks, until they finally took it away, presumably to have its network interface replaced or its firmware flashed or something along those lines. Three weeks hence it has still not been reinstalled.

I can’t help think that with an older clock someone could have simply gone up a ladder and pushed the minute hand back by five minutes and that would have been the end of the matter.

Are we becoming too dependent on high-level technical systems?

A Slower Speed of Light is a first-person game prototype in which players navigate a 3D space while picking up orbs that reduce the speed of light in increments. Custom-built, open-source relativistic graphics code allows the speed of light in the game to approach the player’s own maximum walking speed. Visual effects of special relativity gradually become apparent to the player, increasing the challenge of gameplay.

http://gamelab.mit.edu/games/a-slower-speed-of-light/

Leap Motion demo

June 27th, 2012

Great demo video of Leap Motion‘s new device in action:

And here’s the full accompanying article.

Thanks to @kerridashanne for the link!