From locals to ‘expats’, the response to the book has been most encouraging – when people have seen it their reaction has been: where can I buy a copy? Mostly I have directed them to the online shop.

Widening the number of outlets where the book can be purchased can only further boost sales, and it reminds me of one of the core principles of marketing: the four Ps of Product, Price, Place, Promotion. Get one of these wrong and your marketing campaign is doomed to fail.

Product or brand development, setting the right price and successfully promoting the product are generally given the attention they deserve. Place, however – as in making sure that the product gets to the customer, be it on supermarket shelves, local shops or just available online – is often largely ignored.

But if you don’t make it easy for the customer to purchase your product, you’ll probably lose the sale. If your competitors make it easier to buy an equivalent product from them, then the chances are you’ll miss out on the sale. So much these days is geared to making the user-experience as straightforward as possible – one click to buy, one click to listen, no complicated downloading of the relevant software or having to sign up with a provider just to browse – and this is clearly a good thing. But it does create an imperative to keep it simple for the customer.

Customers no longer have the patience to chase after you and your offering – if you don’t make it easy for them, and certainly if there’s an alternative, they will go elsewhere. So make sure your product has pride of Place.

‘A year in the life of our north east coast‘ is a rich visual document of the coastline of north east England, featuring hundreds of images by local residents of all ages. A full colour, case-bound (hard back) coffee table style book, it’s ideally suited to showing off our amazing coastline!

It’s been a pleasure working with the team at the Dove Marine Lab in Cullercoats; we’re looking forward to the book launch at the Curtis Auditorium in Newcastle on March 12th, as part of Science Week.

The book should appeal to Geordies everywhere

Buy it now on the Newcastle Uni online store

One way of doing this is to strip out the hard drives and destroy them. New hard drives can be put in, and Windows reinstalled. However, that is a little wasteful, costly and takes a not-insignificant block of time.

Instead, I looked for some way to shred the files on the hard drives, and I discovered an excellent Open Source tool for doing this – Eraser.

Now, it is worth describing what the actual problem is here, because it is not obvious. When a file is deleted on Windows, it gets moved to the recycle bin. That means it does not actually get deleted, but instead just gets moved out of the way. At any time you can restore those deleted files.

The recycle bin can be cleaned out or emptied and that will delete the files completely. However, it does not erase the data in the files – the data is still there, and anybody with the technical know-how can recover that data from those files. How can that be?

Files stored on a hard disk consist of two parts: the data and a name in a folder. The name points to the data like an index card in [an older] library points to where a book can be found. Just as you would be able to rip up the index card without the book disappearing from the library, you can remove the name of a file without its data disappearing. All that happens when you delete a file is that the name is removed from its folder, but the data is still there.

The hard disk area where the data is stored is marked by Windows as “free”, so it will eventually get over-written, but there is no guarantee for how quickly this will happen.

So what can be done? This is where Eraser comes in. What Eraser will do is shred the file contents by overwriting it with rubbish – random characters. The idea is that once this is done, there will be no evidence left of the file contents. You can tell Eraser to erase files and folders that currently exist, or you can tell it to go through all the hard disk that is marked as empty, and shred every byte of that disk.

That is what I am doing with the dentist’s machines, and I am now happy that client’s personal details will not get out in the wrong hands.

This subject does go a lot deeper than this when you look at forensic security. For example, data that has sat on a hard disk for a long time, can “sink” deeper into the disk surface and be recoverable by some organisations, even after it has been over-written. However, considering the specialist equipment and skills needed to do that, I can’t see dental records being worth that much effort.

If you do use Eraser, do make a donation. Even a couple of pounds or dollars will help to support this great project.

Essentially the data provides 1.7 million UK postcodes, with their British National Grid Reference, local authority and ward listed for each. The most interesting data is the grid reference, supplied as a full Northing and Easting value. These can be used to calculate distances between postcodes, as well as being able to convert them into Latitude and Longitude data for displaying on maps such as Google’s offering.

The data does lack Northern Ireland and the Channel Island data at present, which can be a problem if you wish to use the data to cover the whole of the UK. The Northern Ireland grid system has a different origin and projection, so care must be taken if those postcodes and data are merged in from other sources. See here for details of The Irish Grid system.

There is a wiki that covers this data, but it is incomplete and has not been updated in nearly half a year, which is a bit strange. I suspect updates are being lost somewhere, because I cannot believe nobody wants to update it (there are technical inaccuracies in the description of the data that someone should have noticed by now). I have made a few additions to the wiki page, so we will see what happens next. If it sticks, I would encourage others to go in and add what you know and discover in the data.

So, what does this data look like? In short, taking into account the areas it does not cover, pretty much complete. I have loaded the current dataset into MySQL, then plotted each postcode as a pixel in an image. Some pixels contain more than one closely positioned postcodes, and a more sophisticated plot would show this, but a simple plot of pixels gives us an idea of what it looks like.

OpenData Postcodes - Great Britain - Click for larger image

Click the image to look at a much larger version with lots of detail. I particularly love how you can see the valleys in South Wales.

This simple PHP script generated the above image. All the table needs to contain are the Eastings and Northings from the Ordnance Survey data. It is surprising how it manages to get through 1.7 million postcodes in about ten seconds:

<?php
$width = 3200;
$height = $width * 1.5;

$db_name = 'opendata_postcodes';
$db_user = 'username';
$db_pass = 'password';

$easting_max = 655448;
$northing_max = 1213660;

$max_points = 2000000;

$db = new PDO('mysql:host=localhost;dbname='.$db_name.';charset=UTF-8', $db_user, $db_pass);

$sql = 'SELECT easting, northing FROM postcode LIMIT :limit';

$stmt = $db->prepare($sql);
$stmt->bindParam(':limit', $max_points, PDO::PARAM_INT);
$stmt->execute();

$img = imagecreate($width, $height);
$background = imagecolorallocate($img, 230, 230, 255);

while ($row = $stmt->fetch(PDO::FETCH_ASSOC, PDO::FETCH_ORI_NEXT)) {
  $x = round(($width*$row['easting'])/$easting_max);
  $y = $height - round(($height*$row['northing'])/$northing_max);
  imagesetpixel($img, $x, $y, 300);
}

header("Content-type: image/png");
imagepng($img);
imagedestroy($img);

Here is the same image with some crude colours introduced to show the density of postcodes.

Colours to show the density of postcodes

As usual, we start with the basic recipe, then try a few alterations each year. The idea is not for any single ingredient to be a prominent part of the taste, but for all to work together to create something new. This time the tweaks are:

• Add orange and lemon. I usually try one or the other, but I think putting half an orange and half a lemon into the pan with a bottle of wine kind of widens the spectrum of the flavours.
• Vanilla – a short length of vanilla pod. This adds a little something to the aroma.
• Juniper berries and allspice – just a couple of each.
• A couple of green cardamom pods, broken open.

A shot of vodka also adds a bit of warmth. We really must not let this become too much of a habit, but it’s cold outside, and it’s Christmas, so we can be forgiven.

The basic gist of the story is that my broadband IP address got black-listed as a SPAM generator, and that meant I could no longer send out email through the broadband mail server. It was frustrating, because it seemed that there was nothing I could do about it, but I have learnt a few tricks now to get over the problem next time.

It all started while repairing a laptop. The laptop had caught a virus or two and needed scanning and updating. Stupidly I plugged it into my home network to get various updates.

Now, on my broadband I run an SME Server. All traffic goes through that server. When I send emails from any PC in the house, the transparent proxy catches those emails, queues them up, then sends them all on via my cable provider’s SMTP server – smtp.blueyonder.co.uk

Normally the server scans all outgoing mail for spam and viruses, and it is usually pretty good at it. Unfortunately, what this laptop was spitting out consisted of extremely simple SPAM emails – just a single sentence and a short URL going through bit.ly. That slipped right through the SPAM scanner and in no time at all, 60,000 SPAM messages were queued up on the server and streaming out to Virgin broadband. Not that I knew this was happening, mind.

At some point, some part of the network noticed this, shook its head slowly, then put my IP address on a blacklist. This blacklist was then used by my ISP to basically cut me off from sending any email through its servers.

The result is that smtp.blueyonder.co.uk simply gave me a message telling me to get lost, then dropped the connection each time I tried to send out mail. This could be seen at the lowest level by connecting using telnet, pretending to be a mail client:

# telnet smtp.blueyonder.co.uk 25
Connected to smtp.blueyonder.co.uk.
Escape character is '^]'.
550-Administrative prohibition. This IP address is a source of spam. Please
550 Contact abuse@blueyonder.co.uk for details of how to fix this.
Connection closed by foreign host.

Switching off the transparent mail proxy of the server and sending direct to smtp.bluyonder.co.uk using Outlook Express or Thunderbird also gave this same error. Using telnet like this though, just removes the possibility that the email client is not set up correctly.

Okay, so need to tell my ISP – the IP address owner – to remove me from the blacklist. To cut a long story short, that proved impossible. There was simply no-one at the ISP with the authority to do so, or even the understanding of what I was asking for.

Next approach: the IP address is poisoned, so let’s get a new one. Easier said than done. I left the broadband modem off all night, I rebooted it many times, I reboot my server many times, but I just could not shake off that IP address. This almost permanent IP address is kind of nice to have normally, but now I  wanted to change it, it was proving difficult.

After several calls to the ISP, I finally managed to talk to someone who knew about these things. “Try bypassing your server and connect your PC direct to the broadband modem”, was his suggestion. I tried that, and behold, a new IP address was allocated. Cool. Just switch back to my server and…hmm, back to the old IP address.

So the Motorola Surfboard modem – or perhaps the cable box at the bottom of the street – was remembering the hardware and trying to allocate the same IP address to the same hardware every time. And it could remember the hardware for at least a full night.

So I guess I would have to change the network card in my server, which was a bit of a bind. Then I struck on this little gem: although the MAC address of the network card is coded into it, the operating system can override (or perhaps reprogram) that MAC address. By changing the MAX address, the network card in the server would look to the cable modem like a different piece of hardware.

I recorded the current MAC address, then added one to it, and issued this command:

# ifconfig eth1 hw ether 00:50:FF:E6:B9:4B

The network card was “eth1″ and the ethernet (“ether”) hardware address was being set to “00:50:FF:E6:B9:4B” (it was “00:50:FF:E6:B9:4A” originally). If you are having this problem with a Windows machine rather than a Linux server, then digging into the driver settings can often give you a box where the MAC address can be edited. Do use this option with care, since MAC addresses are supposed to be unique globally and two machines with identical MAC addresses nearby can play havoc with your network.

One reboot later and I was allocated a new IP address, and email was back online!

Of course, while I am celebrating, someone else will be given my old IP address, be labelled a SPAM creator, and will now have their own problems with their email. I have reported it to the ISP and explained what I think will be happening, and there is not a lot more I can do about it. I feel kind of bad about that, but I have learned never to plug a virus-laden machine into my network again, at least not without some kind of firewall and a virtual private network (VPN) to keep the prying eyes of any virus away from other machines on the network.

Well done Helen!

This MP3 is just a couple of minutes long, and contains a mix of scary Hallowe’en sounds. We used it on an iPod set on auto-repeat, with a small speaker by the front door, just to add a bit of spooky atmosphere.

The sounds came from various Creative Commons sources, and was put together using the excellent Open Source Audacity application. It is not broadcast quality (not that Audacity is not capable of that) but did the job.

halloween-background.mp3 (5Mbyte)

This is the power of Open Source tools and Creative Commons source: the important thing is not that the stuff is essentially free, it is the fact you are given the opportunity to be creative with the tools and media and to customise it without restriction. The right to do so, given to you through the licensing terms, is where the real power lies.

As one of Google’s randomly selected usablity testers, I get to see a lot of upcoming developments before they’re released.

Google’s latest feature is a preview tooltip of each website. Looks like their screengrab tool doesn’t render HTML canvas properly, as shown by the missing text on Siteroom. It also highlights where Google gets its snippet text from: