For those interested, the Ikarus is a two seater microlight aircraft with a maximum cruise speed of 194kph (120mph). See the Ikarus C42 wikipedia page for more details.

I was thoroughly impressed with this regex. I’m not going to reiterate what other people have already explained. So instead I will place links to other blogs that explain this very cool regex primality test.

http://montreal.pm.org/tech/neil_kandalgaonkar.shtml

http://www.noulakaz.net/weblog/2007/03/18/a-regular-expression-to-check-for-prime-numbers/

http://zmievski.org/2010/08/the-prime-that-wasnt

Thanks to <a href=”http://rantsofageek.com/”>Theo</a> for sending me a link to this!

So the internet and ecommerce is now broken?

Don’t panic – there is a fix – it just hasn’t been written yet. TLS 1.1 and TLS 1.2 exist which are not vulnerable to the exploit. However they are not supported by major browsers or web server distributions. I suspect this will rapidly change and support will appear in the next month or so. Also – the exploit is not public and I expect it will be kept a secret for as long as possible.

What to do?

For internet users: Make sure your browser, email client and operating system is bang up-to-date and apply updates immediately as they become available! If your preferred browser is slower than others in getting a fix then temporarily switch to one that does have the fix.

For website owners: If your using SSL at all e.g. ecommerce or email then get onto your hosts once a fix is released and make sure they are going to implement it ASAP. If they are not going to update then move to another host.

For web hosts: Keep your customers informed and hope a fix comes soon!!

I will try to update this post with info on browsers and server software as and when they begin to support TLS 1.1

Bitcasa think they can offer you unlimited storage for $10 per month. They achieve this magic by using deduplication which ensures that data is never deduplicated across any of their servers. So if I upload an mp3 and you upload the same mp3 it only exists once on their disk. Dedupe actually takes it further and breaks every file into chunks and makes sure each chunk is only saved to disk once so if we both have a document where the front two pages are the same – those two pages will only be saved to disk once and so on.

So dedupe is great – but I want to encrypt all my data before it goes onto some untrusted server(s) and so should you. Encrypted data though is rather random and doesn’t benefit at all from dedupe.

So bitcasa are using the following solution:

If you use something called Convergent Encryption – where you generate a key from the file you are encrypting. Then you can encrypt all your data with an individual encryption key for each file. To date this is as much info as they are willing to divulge. However this means you can only dedupe data on a per file basis, so my second example won’t work.

So the only possibility I can think of is that they are breaking files into chunks on the client and encrypting each chunk individually before uploading it to their servers. This will work great but does mean you need to remember an awful lot of encryption keys (millions or possibly billions depending on the chunk size). And this does mean you will need to use Bitcasa’s proprietary client. This means you won’t see any web based access and you won’t see many if any 3rd party applications for a long time.

However that last paragraph is pure speculation at this point :) I’ve signed up for the beta and hope to have more info soon!

To fix you need to change $allowed sites to be an empty array.

e.g. $ALLOWED_SITES = array();

An example of what you may initially find:

$ALLOWED_SITES = array (
‘flickr.com’,
‘picasa.com’,
‘img.youtube.com’,
‘upload.wikimedia.org’,
‘photobucket.com’,
‘imgur.com’,
‘imageshack.us’,
‘tinypic.com’
);

If you have been affected then you need to clear out the infection on your server:

Search your wordpress directory for the base64_decode function and make sure you don’t have any odd looking long encoded strings anywhere.

I already follow most of these rules but will be making more effort with number 8.

www.emailcharter.org.

To fix, just add this to the end of userChrome.css


tabmodalprompt {
background: transparent !important }


The file should be found here: C:\Users\$username\AppData\Roaming\Mozilla\Firefox\Profiles\$letters.default\chrome\userChrome.css

If it doesn’t exist then copy and rename userChrome-example.css to userChrome.css

You may immediately notice that may avatar refused to render at all in the second life viewer. It does render fine in other viewers so I’m not yet sure what the reason was for this. That aside, the media on a prim feature was limited to 4 prims. Any more than that and they just appeared white. The closer I got to the prims, the less problems I had and clicking on a prim would force it to display at the expense of another previously working prim.

I’m not sure what causes this limitation, it may be hard coded into the second life viewer or may be something that can be modified via settings, but despite looking I haven’t yet been able to get it to display a whole wall of media enabled prims.

More on this soon!

Updates soon :)

Is growth in the processing power of folding@Home exponential?

2nd November 2006: 0.2 Petaflops

16th Sep 2007: 1 petaflop (11 months later, 5x increase) Due to PS3s

May 2008: 2 petaflops (7 months later, 2x increase) Due to support of graphics cards via GPU2.

28th Sep 2008: 4 petaflops (5 months later, 2x increase) Due to support of graphics cardsvia GPU2.

27th January 2011: 23 Months have passed and we are only 0.3 native PFlops better than Feb 2009.

In short, yes until the end of 2008. After that we had no additional hardware, no major software advances and one huge recession to deal with. However I think that’s about to change. Once the new version the folding@home client comes out of alpha/beta testing and into the main stream we should see another jump. This is because the latest version of the client utilizes multicore and the gpu by default with no complex setup and no need to download an advanced client. This will mean every new install will be a multicore cpu and a gpu install.

There are nearly 300,000 CPUs folding but only 24,000 GPUs. I will assume the folding@home considers a cpu to be 1 core so we will have to average this a bit as some computers will have upto 6 cores. ‘ll assume an average of 3 CPU cores per computer. So within two years of the new release I expect upwards of 70,000 GPUs to become actively folding. Or to put this another way, an additional 10 Petaflops. During that time I would hope the world has left the recession behind and had a doubling of hardware performance. So with a little luck we could be looking folding@home bringing in around 30 Petaflops in 2013  if they released the new software tomorrow.

The folding@home stats page is available here.