Timestamp based reconciliation: This case differs from the previous one only in the reconciliation mechanism. In case of divergent versions, Dynamo  performs simple timestamp based reconciliation logic of “last write wins”; i.e., the object with the largest physical timestamp value is chosen as the correct version. The service that maintains customer’s session information is a good example of a service that uses this mode.

http://www.allthingsdistributed.com/files/amazon-dynamo-sosp2007.pdf

The witnesses allege a software company NDS, owned by News Corp, cracked the smart card codes of rival company ONdigital. ONdigital, owned by the ITV companies Granada and Carlton, eventually went under amid a welter of counterfeiting by pirates, leaving the immensely lucrative pay-TV field clear for Sky.
The allegations, if proved, cast further doubt on whether News Corp meets the “fit and proper” test required to run a broadcaster in Britain. It emerged earlier this month that broadcasting regulator Ofcom has set up a unit called Project Apple to establish whether BSkyB, 39.1% owned by News Corp, meets the test.
Panorama’s emails appear to state that ONdigital’s secret codes were first cracked by NDS, and then subsequently publicised by the pirate website, called The House of Ill Compute – THOIC for short. According to the programme, the codes were passed to NDS’s head of UK security, Ray Adams, a former police officer. NDS made smart cards for Sky. NDS was jointly funded by Sky, which says it never ran NDS.
Lee Gibling, operator of THOIC, says that behind the scenes, he was being paid up to £60,000 a year by Adams, and NDS handed over thousands more to supply him with computer equipment.
He says Adams sent him the ONdigital codes so that other pirates could use them to manufacture thousands of counterfeit smart cards, giving viewers illicit free access to ONdigital, then Sky’s chief business rival. From the Guardian.

According to sources familiar with the experiment, the 60 nanoseconds discrepancy appears to come from a bad connection between a fiber optic cable that connects to the GPS receiver used to correct the timing of the neutrinos’ flight and an electronic card in a computer. After tightening the connection and then measuring the time it takes data to travel the length of the fiber, researchers found that the data arrive 60 nanoseconds earlier than assumed. Since this time is subtracted from the overall time of flight, it appears to explain the early arrival of the neutrinos. New data, however, will be needed to confirm this hypothesis [ Science Insider]

Time synchronization is a real-time problem, meaning that every link is a single point of failure unless you engineer a lot of cross checking.  In our FSMLabs TimeKeeper software, we work in an environment that is a lot more complex and heterogeneous  than the CERN environment – fortunately we don’t need to get to those levels of precision. But we are operating at the under 1 microsecond level in many systems and it is enormously difficult to keep a running system balanced as network links misbehave, fans turn on and off,  and processor load changes. One thing we are increasingly doing is to monitor multiple time sources and track their relationships – to improve system resilience.

The answer is obvious but few people stop for a second to wonder about this. After all, it is not like Apple has control over all aluminum in the world. Apple were just the first to see the potential of such bodies and began to increase their orders. In just a few years Apple became the main partner of Catcher Technology, a company that possess the necessary expertise to manufacture such bodies. Apple’s production orders amount to 60% of the company’s production capacity. It takes three hours to create just a single body of this quality and, naturally, it is more expensive than a plastic body.[..]Thanks to the production scale these aluminum chassis cost Apple just as much as carbon fiber chassis cost to Sony and just a bit more expensive than plastic chassis for laptops of that price range.[...]

By now you must be wondering: why are they taking it? And if there is a short supply of aluminum bodies all they have to do is buy more CNC machinery and make all the chassis they need. But it’s not as simple as that: it takes up to a year to purchase, install and launch CNC equipment. The management also needs time and courage to allocate large funds to such a project. That is why it was so long before Apple got real competition in terms of laptop chassis. Asus purchased the necessary equipment some time ago but it began to work at full capacity just now and Asus UX21 is one of the first representatives of this work. And due to lower production volumes the production costs of these chassis are higher for Asus that for Apple. Besides, Apple is not paying for the equipment thanks to big binding contracts with their partners. [ Mobile-Review]

While we’re being demanding, we want something that provides the distributed power of Hadoop — without the kilobytes of boilerplate Java and XML; without being forced to sift through gigabytes of log files on hundreds of machines to find our bugs. We want the power without the layers of impenetrable complexity. We want to write simple scalar loops that compile down to tight machine code using just the registers on a single CPU. We want to write A*B and launch a thousand computations on a thousand machines, calculating a vast matrix product together. Julia

Aside from whatever merit the language has, the note about “kilobytes of boilerplate Java and XML” seems both wildly optimistic and on point.

Begin with a recursive definition of a path: EMPTY is a path and if p is a path and n is a local file identifier then the sequence obtained by appending  n to p (on the left) is a path.  And there are no other paths than the ones that can be built from a finite number of applications of this rule.  We can write “n/p” for the path obtained by appending n to p (appending on the left). Let’s require of course that the separator symbol “/” is not in any local file identifier. Other than that, there is no need to say anything at all about the set of file identifiers now – you can think of it as the set of strings that are “/” free if that helps, but they could be anything at all that is “/” free and can be connected into sequences. And  ”/” is just the name we use for the separator, it can be anything at all too.

UNIX style file systems are nearly always constructed on top of flat file systems. That is, we suppose we have a primitive set of “flat file names” of some sort and a map F that maps flat file names to the corresponding file contents.  Flat file names can be the same as local file identifier or different – it doesn’t matter. Right now we don’t have to say much about these flat file names at all but we have some demands on file contents. In particular, files need to be able to “encode”  lookup tables that relate local file identifiers to flat file names. Since we will require that a local file identifier appear at most once in such a table, we can think of the file contents as encoding a function- the “directory function”.  If “i” is a flat file name and F(i) is defined, we need to be able to associate F(i) with a type: plain or  directory (to start). Plain is just some data. If F(i) is defined, and F(i) has type directory, there is some function d= D(F(i))  we can decode from F(i) so that for some finite set of local file identifiers, “d” maps those identifiers to flat file names.

The idea is that we can start with some flat file name “i” and a path, say,  p=a/b/c and follow p from “i” as follows. First get i’=D(F(i))(a) if F(i) is a directory. Then get i”= D(F(i’))(b) and i”’= D(F(i”))(c) – assuming that the intermediate flat files are directories and they encode functions that map the flat file names “a”, “b” and “c”.  There’s some complexity because we’re not assured that everything will work out – we may only be able to follow a path partway before coming to a dead end.

So define a function R to take a flat file function F, an initial flat file name “i” and a path p and produces either a terminal flat file name or FAIL if the path cannot be followed all the way.  First we do the easy case R(F,i,EMPTY)= i.  The recursive case is

Associate F with a special flat file “r” – the root file. Then we can define U(p) = F(R(F,r,p)) if R(F,r,p) is not FAIL and let U(p)= FAIL otherwise.

And that’s it – except that now the flexible nature of the file system becomes clear. Let’s add a new file type “indirect” so that if F(i) is indirect, then we can extract a flat file map and a root flat file name from the contents. That is, if F(i) is an indirect file we can produce (F’,r’) = X(F(i)) where F’ is a flat file map and F’(r’) is a directory under F’.  Say “i” is a properly defined indirect file under F if and only if F(i) is indirect and for (F’,r)=X(F(i)) we have F’(r) as a directory. We can now redefine R as follows to switch flat file systems on an indirect file.

Note that the first definition of R is obviously primitive recursive – because we lose one element of the path sequence on each recursive step – but it’s not obvious that the version of R with indirect calls must terminate. The final condition on the indirect case assures us that at least every second step must remove one element from the path.

The A5 processor – the brain in the iPhone 4S and iPad 2 – is now made in a sprawling 1.6 million square feet factory in Austin owned by Korean electronics giant Samsung Electronics, according to people familiar with the operation.
One of the few major components to be sourced from within the United States, the A5 processor is built by Samsung in a newly constructed $3.6 billion non-memory chip production line that reached full production in early December

http://www.reuters.com/article/2011/12/16/us-apple-samsung-idUSTRE7BF0D420111216

 

A supply of tea with milk and sugar would be nice.  If it is tea I
really like, I like it without milk and sugar.  With milk and sugar,
any kind of tea is fine.  I always bring tea bags with me, so if we
use my tea bags, I will certainly like that tea without milk or sugar.

If I am quite sleepy, I would like two cans or small bottles of
non-diet Pepsi.  (I dislike the taste of coke, and of all diet soda;
also, there is an international boycott of the Coca Cola company for
killing union organizers in Colombia and Guatemala; see
killercoke.org.)  However, if I am not very sleepy, I won't want
Pepsi, because it is better if I don't drink so much sugar.

There’s more. A lot more.

http://en.wikipedia.org/wiki/Dennis_Ritchie

The US military’s unmanned Predator and Reaper drones are continuing to fly remote missions overseas despite a computer virus that has infected their US-based cockpits.
Government officials are still investigating whether the virus is benign, and how it managed to infect the heavily protected computer systems at Creech Air Force Base in Nevada, where US military pilots remotely fly the planes on their missions over Iraq, Afghanistan and elsewhere.
“Something is going on, but it has not had any impact on the missions overseas,” said a source, who was not authorized to speak publicly.
Armed tactical unmanned planes have become an increasingly valuable tool used by the US military to track and attack individuals and small groups overseas, but the virus underscores the vulnerability of such systems to attacks on the computer networks used to fly them from great distances.
Rob Densmore, former US navy airman, told Al Jazeera that the infection was a common keystroke logging virus – which registers the keystrokes pilots use to control the unmanned drones from afar.
“It has to have a point of access, so we know that thumb drives – basically USB drives – are used to upload navigational information, guidance information to Predator and Reaper drones.
“And if there’s a way somehow that that information, or that thumb drive, can come into contact with a network or with the internet, that’s where the danger is because that basically means that information can be carried across from the Reaper drones.”

http://english.aljazeera.net/news/americas/2011/10/201110816388104988.html

Government approach to security can be described as designing an unsinkable boat that has no doors between compartments and then, to make it usable, cutting a random and increasing number of undocumented holes between compartments.