September 2005 Archives

I have a rather weird network setup at home. Partly due to having both a sensible ADSL connection from Black Cat and an NTL cable modem as backup, partly because I have native IPv6 (over the ADSL). I used to just use a normal PC with a USB Speedtouch plugged into it, but a while back I managed to get an ASUS WL-500g setup to do the job (it has USB for a flash drive / webcam, but this got the Speedtouch plugged into it). It does the job, but is somewhat hacked up. Plus I think the USB ADSL modem adds extra latency and can sometimes be dodgy.

So, when I discovered that the Netgear DG834G had source available for all the important bits (wireless, ADSL, ethernet) I was intrigued. I already know a bunch of people who have this router and are happy with it, so the knowledge that it was more hackable than the average ADSL router made it very appealing. As it happened quinophex (who seems to becoming my hardware pimp) had a spare one, so we did a deal and he brought it round today.

After checking it actually worked and could connect to my ADSL line it was time to open it. The screws are hidden underneath the little white feet and appear to be torx style, but I had a normal flathead that did the job (I should really get myself a larger set of screwdrivers). At first I couldn't spot any headers, but then I saw JP603 half hidden under a sticker with the MAC address on it. Ta da. 4 holes, one obviously ground, one looked non connected, 2 had tracks leading away from them.

I found a piece of veroboard in my toolbox and realised I'd put off building my MAX232 level shifter for too long. After much too long (but no burnt hair) I'd soldered up the simple circuit and was ready to try it out with my Linksys WMA11B. Using Andrew Wild's excellent serial port instructions I had an adapted device to test with. Hooked it all up and it didn't work. Bah, think I. My soldering sucks. No, serial ports suck. ttyS0 has decided not to play nice on my desktop machine. One USB serial port adaptor later and I can see the Linksys boot. Yay!

So, onto the Netgear. A bit of prodding (and dodgy soldering) later and I have a console. Yay! I can see ADAM2 and I can see the kernel boot and get a busybox login. Rock. Now I just need to work on getting a better firmware installed that can handle what my Asus is doing at present.

I finally got the loan of quinophex's Magellan 315. So I went on a wander with it, to see how it faired. (The advantage of a handheld device is that it's self contained, so I can go for a walk with it easily rather than having to bring the USB device and a laptop with me.) However I'm still getting the same offsets compared to the Landsat pictures when I compare on OSM or osm-editor locally. I've set my datum to WGS84, which I understand is the default for GPS. I've made sure the GPS can see a reasonable number of satellites (5 locks is good, right? With an extra couple of marginals?). I was walking, so it's not at any great speed. And yet, as with my USB device, the track is slightly down and to the left.

I'm planning on going on a drive with both devices hooked up to the laptop so I can compare the data from each at the same point in time, but does anyone have any idea why I might be having these problems? Take a look at a screenshot of osm-editor (579KB, 1280x1024) to see what I mean; the track at the bottom is clearly shifted downwards from where the dark line of the road is.

The English don't really seem to understand Northern Ireland (maybe the rest of the world doesn't either, but I don't get exposed to them as much). I was born in Northern Ireland and lived there until I went to university in England. I still go back there several times a year as my family live there.

The first indication I remember that something was wrong was when I tried to buy car insurance for the first time. I was living in England (car insurance in Northern Ireland is more expensive, and most of the online options won't cover it; I understand this is because injury claims are [or possibly used to be] awarded by jury there, as opposed to by a judge on the mainland. Juries apparently are likely to award more.), and when I was asked if I'd lived in the UK all my life I said yes. Except they knew about me being from Northern Ireland or something (I'd probably asked about being covered for driving back there) and claimed that it wasn't part of the UK. And when I said that yes it was they fell back to "but it hasn't always been". Er, yes, it has. For as long as Northern Ireland has existed as an entity distinct from the rest of Ireland it's been part of the UK. And it's been part of the UK since 1801 anyway. Long before I was born thankyouverymuch.

Since then there have been minor incidents; for example the Post Office clerk not being sure if it cost more to send things to Northern Ireland (she got corrected by one of her coworkers though, and I know that sometimes they won't guarantee delivery times so I forgive her that).

Today I get asked by a friend if Northern Ireland is part of the UK phone network. WTF? Yes. It is. It's part of the UK. No, really. I'll say that again so it sinks in. Northern Ireland is part of the UK. BT are the monopoly telephone provider there. 3, O2, Orange, T-Mobile and Vodafone all provide service there. You don't need a magically different mobile phone contract (the person in question was particularly interested in short codes) if you live in NI rather than mainland UK. Gah. What are these people taught?

(I didn't confuse the issue when explaining to my friend about NI being part of the UK by saying that some call charges do differ; last I investigated ringing Ireland from Northern Ireland with a BT line was the same price as ringing the rest of the UK. Equally it was cheaper to ring NI from Ireland than to ring the rest of the UK. My information is several years old now as I tend to just use my mobile when I'm back there. There's also the oddity about dual citizenship; anyone born in NI has the right to Irish citizenship as well if the choose. Oh, and while I'm ranting, why is the adjective for someone from the UK "British"? Britain doesn't cover all of the UK. I wasn't born in Britain yet I'm British. Can't I be UKish or something?)

Recently security.debian.org has been having some problems with maxing out its connection due to an X update. This reminded me of a conversation I had at DebConf5 about the feasibility of a Debian anycast instance. This was originally under the guise of ftp.debian.org, but there's no reason it wouldn't work nicely for security.debian.org as well.

The idea is that Debian would obtain a /24 of PI (or something unlikely to get filtered anyway; I think anything smaller wouldn't work) and their own AS. They'd then host instances of f.d.o/s.d.o around the world with ISPs that would route this AS for them. This would mean that big sponsors able to provide global routes would still be able to do so, but smaller sponsors (like Black Cat) would still be able to help out by announcing the route to their peers.

You'd need the servers involved to all be reliable push mirrors, so that they're as close to being in sync as possible. And I'm not sure how well TCP works over anycast; assuming stable routing I can't see why it'd be a problem (does the Akamai service work this way?). Certainly it seems to be quite common for major DNS servers these days. But it could end up with quite a few decent local mirrors with no work required on the part of the users to take advantage of them. Am I insane?

I had a conversation a few weeks ago with Tristam and some other people about direction finding in terms of car navigation systems, and how I felt it reduced to a weighted directed graph and that it should be possible to build from a large enough set of GPS logs. There was general agreement that this wasn't unreasonable. This prompted me to actually see what was out there, which led me to OpenStreetMap, who have been going for over a year now and see to have a reasonable number of people involved.

They lack any data around Norwich however, so I thought I'd see what I could do to remedy that. I bought a basic USB GPS device, hooked it up to my laptop, installed gpsd and gpsdrive and went for a test drive. gpsdrive seemed to be doing the right thing, with the track it drew matching up with the map being displayed. However when I uploaded it to OSM it seems to be out by a reasonably constant factor. This has led me into the tricky world of GPS datums and hoping that that's what at fault rather than it being the fact I bought a cheap Haicom Hi-202 rather than something more expensive. quinophex has a Garmin however, so he's going to lend it to me so I can run the 2 side by side and see what happens. It'd be really nice if I discovered it's just a conversion thing and that the tracks I got of a trip to and from Redbus could still be imported...

Anyway, if you do GPS stuff at all I'd highly recommend uploading some tracks of your local area and even potentially doing some markup of nodes and streets; if everybody just did a little bit local to them and perhaps a few longer journeys then things should start to get linked up and filled out, which would increase the appeal a lot.

I suspect these apply to lots of Sony Ericsson phones, but I know they definitely work with my v600i and I couldn't find them anywhere all together.

• Asking the phone for a non existent file via obexftp makes it very unhappy; apparently often to the point where the phone needs turned off and on again. This is bad.
• ussp-push is your friend.
• To send a vCard (or many in one file) to the phone, do: ussp-push <BT ADDRESS>@5 <local vcard file> pb.vcf. The phone will recognise the "pb.vcf" (in particular the .vcf extension I believe) and ask if you want to import the contacts.
• To send a Java App (ie a .jar file) do: ussp-push <BT ADDRESS>@5 <app.jar> <app.jar>. Again the phone will recognise the extension and then ask where you want to save it - under Games or Applications.
• The normal AT dialup/GPRS command set works fine on rfcomm channel 1.

I'm a keen believer that we need some more interesting applications for pie-in-the-sky technology. My favourite example is the time machine fridge. What better use for the idea of time travel? Every time you need an ingredient from the fridge, not only do you have it - it's fresh! I was explaining this idea at TFM's BBQ on Saturday and Ian Snell came up with a potentially better idea; the stasis fridge. Want things to stay as fresh as the moment you put them into the fridge? No problem. What to keep your hot pizza beside your cold beer? Done.

My other neat idea is the wormhole router; get round that pesky speed of light limitation of packets crossing the Atlantic by having paired routers with a wormhole between them. Loadsa bandwidth, tiny latency. No danger of a trawler cutting your fibre!

The problem, of course, is that no one's actually got round to inventing time travel, stasis or wormholes yet. Bah.

My second gadget in the past week was a new laptop. I've discussed this before and ended up with the R200. Built in bluetooth + wireless and 512MB RAM; more than my old N200. I'd seen Chris Walker's R100 at Steve's annual August BBQ and he said he was happy with build quality, so that convinced me. It's very nice; light, looks good, even came with a little cloth to put between the screen and keyboard when it's shut (numerous people have told me they put a piece of paper in or similar for their laptops to avoid finger muck getting on the screen, so I thought it was a nice touch by Toshiba).

Installation was fun (in a sick, I like fiddling sort of way). No removable drives. And the in built ethernet isn't supported by a stock kernel. Hmmm. So I ended up booting from an SD card that happens to have GRUB on it in my SD/USB convertor, and then reading the mini install ISO off my iAudio, and then doing the rest of the install over the network using a PCMCIA 8139too based card I had lying around. If I'd had a big enough SD card or USB memory stick the easy solution would have just to do a full install off that, but I don't.

The whole thing is patchtastic. The internal GigE ethernet isn't supported by 2.6.13, but you can download a patch from Marvell. The internal wireless is Atheros, which needs the non-free madwifi driver (though I must try the Free ath-driver at some point). Bluetooth appears as a normal USB device, supported by hci_usb. However it doesn't appear on the bus without an ACPI patch to allow toshset to enable it (I possibly could have enabled /dev/toshiba support as well). The video is an i915 chipset, which isn't supported by the XFree86 in Etch, so I'm waiting for xorg to propagate from Sid before installing X. Good job I'm a text mode junkie, eh?

That sounds like a bad review, but I'm really happy with it. Everthing is actually supported (well, except the SD slot and the fingerprint reader), just not in the default kernel. It's light, it looks cool, I'm easily getting 3+ hrs battery life out of it and that's before I've looked at doing stuff like laptop-mode or auto cpufreq.

Oh, and although I'm running Debian on it, the Ubuntu R200 wiki page was really useful as a starting point.

This past week has been a week of gadgets. My Orange contract ran out a couple of weeks ago, so I was due an upgrade from my SPV E200 (more on that monstrosity later). I've been with Orange for 6 years now and although I've found them fine for voice their data performance has been patchy. I'm not a heavy user, but it's annoying to not be able to rely on it at all. People Who Know seem to rate Vodafone as the best UK data network so I went looking to see what they could offer. At first the Nokia 6230i looked like the best option, but then I noticed the Sony Ericsson v600i (which I think is just a Vodafone branded K800i). This is a 3G phone that isn't a lot bigger than the 6230i and still manages to be smaller than the SPV.

So it arrived Tuesday week ago, but unfortunately as I was porting my number from Orange it only became active this Tuesday. Bit odd as at first it worked for outgoing calls but incoming were still going to Orange, but it sorted itself out within a few hours. Whole process was reasonably smooth except for a complete inability to order online if you want to port a number; I ended up having to ring up. How retro.

Anyway. Kathy disappeared off to her parents yesterday, so I made my first video call last night (she has a phone on 3 as mentioned previously). It's actually pretty neat; jerky, but enough to tell facial expressions that are held for longer than a moment. I dread to think how much it cost and I doubt I'd use it in general, but it's Pretty Cool.

Then, while fiddling with it on the way to London today (a joyous day in the datacentre) I discovered it does IMAPS. And actually checks the cert. I'm impressed. Now I'm on my way home I had a fiddle with getting dialup over Bluetooth working and that seemed relatively straightforward too.

So far the downsides I've found are that it really doesn't want to talk OBEX to the telecom/ directory, which I understand to be how you pull the phonebook and things off the phone. I don't know if this is something I'm doing or if I'll have more luck with SyncML. The other problem is a lack of decent games on it. I want something simple and addictive to pass the time on trains. There are a couple of demo games, but both a bit too complicated for instant addiction. Brett tells me sending Java apps should be a simple matter of an OBEX upload, so I'll try that later and see what I can find.

All in all I'm happy with it so far. We'll see how I feel after the first month I guess, when the bill's hit. :)