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Submission + - x86 Computation Without Executing Any Instructions (usenix.org)

jones_supa writes: Trust Analysis, i.e. determining that a system will not execute some class of computations, typically assumes that all computation is captured by an instruction trace. A team at Dartmouth College shows that powerful computation on x86 processors is possible without executing any CPU instructions. They demonstrate a Turing-complete execution environment driven solely by the IA32 architecture’s interrupt handling and memory translation tables, in which the processor is trapped in a series of page faults and double faults, without ever successfully dispatching any instructions. The 'hard-wired' logic of handling these faults is used to perform arithmetic and logic primitives, as well as memory reads and writes. This mechanism can also perform branches and loops if the memory is set up and mapped just right. The lessons of this execution model are discussed for future trustworthy architectures.

Comment Re:Places Needing Stable IT Staff (Score 1) 472

  I get your point but:

  In todays economy there are still a few pockets of stability and they tend to be in the
  places I put in this list. Not all positions, but some. E.g. We do hire some temps but they know they
  are temps and are about 5% of the workforce. I obviously don't work for Microsoft.

  These are places where they need (and more importantly: know they need) some working memory
  of how the place is runs. They are places where it is a big hairy deal to hire or fire certain positions.
  They are of a size that it is not unusual for exactly ONE person to know how to do a critical task.
  Even if cross trained, there is usually one (or maybe two) people who are really good at that critical
  task so you better have responsible people who would like to stay awhile.

  I am a sysadmin, I've been here for a decade, my most junior co-sysadmin has been here for years.
  No degree by the way, just a massive list of accomplishment. Me, I have a degree in a related field
  and fewer accomplishments.

  Even our web people have been here for years. That said, we all sometimes find ourselves working
  outside our original job descriptions from time to time. Money is tight but they want us to stay as long as
  we are doing a job that needs (or will soon need) doing.

  My particular organization has been through many expansions and contractions in the last century
  but makes extraordinary efforts to keep sharp people. My part is to stay sharp and grow. We have
  let go sharp people in the recent contraction, but we try to avoid it.

  In 2013 this is an exceptionally good situation to be in I know but these situations exist and are
  worth looking for.

Comment Places Needing Stable IT Staff (Score 2) 472

Emphasize stability if you can, this can make age a plus. Not that age
guarantees stability or youth means not responsible but you are more
likely to be considered in a place looking for stability.

County government,especially smaller counties. They typically run on shoestrings but they
can really appreciate someone who can keep systems running well. Likewise midsize
towns and cities.

If you have some oddball skills, that can be a plus. In fact if you know INGRES, are willing
to live in Seattle and are stable: Drop me a line!

Medical computing often wants someone a little older. Banking will often hire someone older.

  Midsized organizations 100-500 can be an especially rich vein, places that have been around
  awhile so gray hair isn't unusual and small enough not to automate the initial job search. They
  also often have enough work to keep a small team busy.

  Surprisingly, these can be research departments at
  Universities (yes, they sometimes happily hire people without degrees. Who
  better knows a degrees worth for day to day computing? Arguing with the person
  with an MS who wants to convert everything to Python is not fun.).

I think it a fair bet there are security companies watching the news
that are going to be more accepting of someone older than they were
a month ago.

Comment Socratic Dialog (Score 1) 716

Some of us need the Socratic Dialog. I was driven to learn about mathematics. I had real drive and read a LOT. I was smart. Yay me. I managed to mis-learn a heck of a lot that way. It wouldn't have been so bad later on but I mis-learned some basic things. It was unpleasant and time consuming to go back and edit out what I got wrong and I needed someone outside my own head. I couldn't see what's wrong in my own head alone. Sadly, even in college, that kind of teaching isn't available so much but it's golden.

Comment Re:I'm Cured! (Score 1) 602

As funny as that is: "I'm Autistic" seems a more powerful social excuse than "I have Aspergers". In any case: most of us whatever-we-ares still need to do our limited best not to be jerks. If we want a social life: Labels are more of a tool to find strategies to be less of an asshole than an excuse for being one. ...and pathetically, getting all pedantic on a funny joke is probably itself an example of assholery. Sorry dmomo.

Comment MANY Daylight Savings Times, Not One. (Score 1) 475

If you co-ordinate with people in different countries this gets to be pretty annoying. Seattle PST/PDT doesn't change the same days as in, for instance: Victoria, Australia. Which aren't the same days as say, London, England. This makes co-ordination a bit of a drag. The deltas shift around every Spring and Fall: not once, but several times. UT makes it manageable but it still grates.

Further, the few farmers I know couldn't care less.

Comment An Argument for Archer (Score 1) 618

I liked Archer and much of the series (except the theme) because the ship was so limited. By definition almost every spacefaring race they came across was more technologically advanced and they had to deal with that. He was often ignorant, if well meaning, because humans just hadn't been around that much. He had to clean up some of his own messes (not a common theme for Kirk) and actually live with the Prime Directive; leaving a whole species he could save...but doesn't. He had to deal with the Vulcans, who were not entirely wonderful in Archer's experience AND had to ask for their help.

In short: Archer had to successfully play with the big kids in a toy ship.

Comment ITU attempted to replace TCP/IP back in the Day (Score 5, Informative) 171

OK, many people involved are probably retired or dead by now, but way back in the early eighties there was the ISO networking standard which was to replace TCP/IP and it was HEAVILY pushed by ITU. It had it's charms but man it was heavy.

"ISO will replace TCP/IP in 5 years" was a real thing. After 10 years the phrase became a joke. Now it isn't even that.

Ever wondered why the L in LDAP stands for "Lightweight"? It started as a radically simplified version of ISO directory services.

Almost nobody used ISO (including ITU, which at the time preferred paper over networks internally) but ITU really pushed it over that toy internet thing. They also charged a lot of money to buy the bookshelf-meters of ISO documentation...only available on paper for the most part.

It is probably completely unfair to the ITU of 2012 but I find myself worried whenever they are mentioned in the same breath as "internet".

Comment Above Your Pay Grade: Some consequences (Score 1) 349

If you are asking these questions (they are good questions) this is likely WAY above your pay grade. You need to find the people that know the regs and tech and get them involved. Now. Slashdot is nice but it's nowhere near sufficient and much posted will be simply wrong if you care about your career even when technically correct (and a lot won't be).

The number of ways to screw this up (assuming it is even allowed) are mind boggling and there are at least three major categories of ways to screw up: Military, Technical and Political.

Please note you may be opening a can of worms not just with the Navy but the country you are berthed at! There are places where encrypted internet traffic is not looked upon kindly.

The trade offs are non trivial. Having on-ship access means devices are more likely to stay on board, which is a very good thing. Installing high speed internet access can make any data leaks go faster, not a good thing. If you do this you need every t crossed and every i dotted.

This must come up a lot and I guarantee the Navy has a stack of rules somewhere. If you are lucky: self-consistent ones.

...and a random thought: Would setting up WiFi be "interesting" in compartmentalized steel ship?

Comment Mathematicians Teaching Statistics (Score 1) 265

Have you had statistics training? If not, please get a little.

I may be the only mathematician who had this problem (I wasn't all that good) but Statistics threw me for a loop at first (I was briefly fairly competent eventually). Statistics isn't calculus; calculus is a big part of classical statistics.

A pure mathematician hitting statistics cold may have almost as big a problem a student with little mathematics. Mathematics knowledge can actually get in the way at first.

The big breakthrough for me was realizing a random variable isn't much like the variables I was used to. That I had to think differently. Once past that, I was at an advantage again because I had gotten through undergrad calculus and linear algebra but until then, I was MORE confused than the soft science majors around me.

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