text:
Talk:PaX

Questions?
Anyone have any need for knowledge that I didn't fill? This is a basic rundown of what PaX is and does, and I'm no expert.

PaX bad for non-C programs
It should be noted that PaX breaks a lot of applications that try to manage their own heap, i.e. by using a garbage collector. Notable examples include SBCL and CMUCL which try to setup a heap layout that conflicts with address space randomization of PaX. The funny thing is that PaX is completely worthless for these Lisp compilers, as it is practically not possible to produce buffer or integer overflows. --Boelthorn 22:55, 18 July 2006 (UTC)

Anon author; not good?
"PaX at the time of this writing is not in the mainline kernel because The PaX Team does not wish to advocate it for mainline inclusion at this time."

... not to mention that, in the wake of the recent unpleasantness, the chances of Torvalds accepting an anonymous patch are zero? That was the very first thing that sprang to my mind when I saw the authors were playing anonymity games. I mean, wtf? Why the anonymity? There's going to be something relevant to discuss there. This is not normal practice, at all - David Gerard 06:46, 15 Jul 2004 (UTC)

It's ok to be anonymous
Whether I'm SCO Group, Jason Voorhees, or John Moser, the same rules apply: I release my work, I license my work, I hold the copyright. If an anonymous contributor releases his work under the GPL or BSD license, he has as much a chance of suing you as a non-anonymous contributor. It's the license you need to worry about, not the man's name.

Also, it's perfectly acceptable to remain anonymous; I didn't give up my name until a few months back. He shouldn't be forced to give up his by the open source community; although it's up to Linus if he wants to put PaX in the kernel.

--Bluefox Phoenix Lucid 16:39, 16 Jul 2004 (UTC)
 * BUT, anonymity looks suspicious, and in the absence of anything sensible to do, going after the suspicious looking always tempting. Thus, it's not entirely irrelevant in practice. ww 19:14, 21 Jul 2004 (UTC)

--WpZurp 06:43, 11 Aug 2004 (UTC)
 * Or, to be more blunt, anonymous contributors are not necessarily the creators of the source code. The anonymous contributors could have swiped the source code from someone else and, thus, aren't even legally entitled to place the work under GPL. To be even more paranoid, SCO could covertly leak source code to these anonymous contributors and then entrap Linux for copyright violation after including PaX. Wikipedia is safe (we hope) because contributions come in dribs and drabs but including a substantial project like PaX into the Linux kernal is like being offered a poisoned apple.

 * A good legal (though paranoid legal) point. Since legal paranoia is an important aspect of legal reality, it's a significant one. In this case, however, Linux (Linus) could presumably demonstrate a lack of intent which would militate against the worst (most paranoid) penalties. On the other hand, it could be claimed that acceptance of the anonymous (though un permissioned) code demonstrated a lack of reasonable diligence against this sort of possibility. Insufficient paranoid practice by Linus, in effect. Which would militate for increased penalties.
 * I sound like a lawyer don't I? On the one hand..., on the other hand..., and so on. The only thing missing is the large billing. It may be that in many respects, Shakespeare had it right.
 * On a related subject, it does appear -- as nearly as my sensors can penetrate the fog of litigation (Clauswitz should have been a lawyer) -- that SCO (nee Caldera and so on) is digging a deeper and deeper hole for themselves. And the collapse will be most spectacular, and vastly amusing, when it comes. Soon, soon... ww 13:42, 11 Aug 2004 (UTC)

clarity edits
Blue, I got some time sort of free and went through the first couple of sections doing clarity edits. I trust I haven't so grossly misunderstood something that I've lost meaning. And I hope that clarity has been increased; some unfelicities of language are at least corrected. The cost (aside from time) is some additional verbiage giving some of the background the less than expert might find useful. Tell me what you think. ww 19:14, 21 Jul 2004 (UTC)

Needs work ;)
Pretty good. You've been helpful :) Though, you or the other editors have added factual and grammerical errors, or misleading statements; whoever said "no data is lost" is FLAT WRONG, because you can't save application data in the middle of a PaX kill ;)   But the stuff is salvagable and mouldable into a better form than before :)

I guess I"ll have to give this a hard re-read later and clean up :)

--John Moser 16:12, 22 Jul 2004 (UTC)

copied from featured article cand comments

 * please ensure that comments and changes are entered at Wikipedia featured article candidates, it is not sufficient to do so only here.

From the FAC: === PaX (Linux) === Contested -- July 13

self-nomination

PaX is an article about a security patch for Linux. I enjoy using PaX, and wished to show my support by writing an article on it. As the article is well written, and work that I am particularly proud of, I felt I could nominate PaX for FA.

The article is very accurate, as I've written most of it from my experience and from data I've read on PaX, and have had the developer run over it for me to make sure there were no factual issues.

Even though I am a hardcore PaX supporter, I leave my personal feelings about PaX out of the article. I believe that I can best support PaX and the diffusion of information about it by avoiding any propagandist slur or influence in the article itself. My goals are to present a complete and concise description of what PaX is and what it does, and I believe that I have achieved this in PaX.

I believe that the article is written in such a way that it only presents the user with complete and concise information about what PaX is and what it does, and leaves him with only deep technical questions which can be answered by visiting the PaX homepage--linked to in PaX--and reading through the several pages of technical documentation. This is exactly what an encyclopedia is supposed to do.

--Bluefox Phoenix Lucid 04:10, 14 Jul 2004 (UTC)

 * Object. My general impression is that this is a long way off from being a feature-worthy encyclopedia article and currently reads like a piece of technical documentation. I'd recommend a spell on Peer Review first. Some specific problems: 1) Who is the author of the patch? The article should mention this. 2) The lead section is incomprehensible to a non-specialist, even to a computer science graduate. It's OK for a Featured Article to be technical, but the lead section should provide an overview, and provide definitions or wikilinks to essential concepts which might be unfamiliar for the reader. 3) Moreover, throughout the article, more links need to be given to technical concepts mentioned, even if the articles don't yet exist. 4) Any famous users of this patch? — Matt 04:34, 14 Jul 2004 (UTC)
 * Explain (2) please. Do computer science graduates not know what occurs inside a computer?  Particularly, do they not understand the basic concepts of memory managment and virtual memory?  Or does "Least Privilage" confuse people?  Nonetheless, I concede that somehow I managed to spit out incomprehensible gibberish grammerically.  This has been rewritten.  --Bluefox Phoenix Lucid
 * Sure; computer science graduates do indeed have at least a vague idea of what goes on inside a computer. However, there's probably few who could understand "Executable Space Protections to take advantage of or emulate the functionality of an NX bit; and Address Space Layout Randomization to obfuscate ret2libc" without further explanation, and the article currently offers no way of finding out the meaning of the undefined technical terms. — Matt 19:45, 14 Jul 2004 (UTC)
 * Check my work, I've added a wikilink but the page doesn't exist. Also, check currently section 1.1.  --Bluefox Phoenix Lucid
 * I think I satisfied (2) and (3). Please check my work and strike if you agree.  --Bluefox Phoenix Lucid
 * (1) and (4) I've satisfied. --Bluefox Phoenix Lucid
 * Object. I agree with the above objections.  Also, the article is lacking a discussion of why PaX is significant.  The feeling I get from the article is almost that PaX is just one security patch that implements several ideas implemented by other people.  Does PaX make a technical contribution?  Is there a significance to how it affects society?  What's the impact?  Without being POV, of course, the article needs to make the argument.  Zashaw 05:06, 14 Jul 2004 (UTC)
 * I can't help your "feelings" that you get from the article. I show what PaX supplies.  It supplies a lot, and there's no reason why supplying more than one thing should imply that you stole the ideas or code from everyone else.  The best I can say is, look at the date given in section 3 for when PaX came around.  It grew from there.  --Bluefox Phoenix Lucid
 * Added section 1. --Bluefox Phoenix Lucid
 * I'm comfortable withdrawing my objection. I found section 1 very helpful.  One thing it doesn't address is how PaX differs from other security patches or schemes, both for Linux and other OSs.  I know little about the area, but would think that there must be other similar patches, and something contrasting PaX somewhat more would be nice.  On a related note, it'd be nice to know if the schemes that PaX implements are new to PaX, or if they've been around before, but were just integrated into PaX.  Zashaw 21:11, 23 Jul 2004 (UTC)
 * In addition to that, it needs information about 'why the patch is needed'. Why isn't it in the mainline kernel?  Morwen - Talk 06:22, 14 Jul 2004 (UTC)
 * As I understand it, the author isn't ready to advocate PaX for mainline yet, as it doesn't work on all architectures. --Bluefox Phoenix Lucid
 * I noted this on the article now in section 1. --Bluefox Phoenix Lucid
 * Object as of this date's version. The article covers a signficant approach to a serious problem, has more than merely Linux relevance, and deserves a WP article. There is, buried in the version of this date, a possible featured quality article. The technical issues cannot be described without some obscurity to the previously unexposed and so this is acceptable in such an article. However, even so technical an article can be structured as to help such a Reader. This version is not. Newspaper pyramid structure is redundant, overly wordy and repeats too much, but it does put the most approachable account right at the top. This article does not do so, and for so technical a topic, this is a major problem for the Reader not already familiar with the topic. There is some discussion of the virtues of good 'narrative arc' in articles on technical topics at Talk:Secret sharing which may help illuminate my objection. ww 20:24, 14 Jul 2004 (UTC)
 * OK, this interests me. Would you be willing to help with this?  The most important part of an article is its factual accuracy (which implies NPOV), but a very close second (almost a gemini) is how well it conveys the information to the reader.  If I'm missing on one of these points (you say the second), that's bad.  Should I move section 1, Why PaX is significant, to the top?  --Bluefox Phoenix Lucid
 * Illustration needed. A diagram helping explain the concept to the less technical reader would do nicely. - David Gerard 21:34, 14 Jul 2004 (UTC)
 * Bask in the awesomeness of my obvious lack of drawing skills :) --Bluefox Phoenix Lucid
 * I misread the instructions earlier and have been striking out peoples' objections as I satisfy them. Please strike this one if you find the diagrams adequite.  --Bluefox Phoenix Lucid
 * Those are just what I was thinking of :-) Now I would like a shrubbery something theoretically main-page-friendly. That's not an objection to FAC status, btw, just a request for a nice bit of eyecandy. - David Gerard 10:32, 15 Jul 2004 (UTC)
 * I'll see if he'll let me use the PaX Tux. :)  --Bluefox Phoenix Lucid
 * Anyone is free to prettify my diagrams; but you should note that the simplistic display brings more attention to what it is rather than "ooh eye candy. . . wtf was this supposed to be?" Go ahead and make wavy, curvy, 3D cute things if you like; but try not to make it less point-in-face.  :)  Also try to keep the same size. --Bluefox Phoenix Lucid 16:17, 16 Jul 2004 (UTC)
 * Not an objection: A bit more on why the authors want to remain anon would be appropriate. Particularly given that, in the wake of the recent unpleasantness, the chance of an anonymous patch ever getting into the kernel is zero. This sort of behaviour from an open source author is more than just somewhat odd, it's distinctly weird - David Gerard 10:32, 15 Jul 2004 (UTC)
 * He says, "tell him 'just because' ;P" --Bluefox Phoenix Lucid
 * How convincingly childish of him - David Gerard 20:11, 15 Jul 2004 (UTC)
 * No law says he has to give you his name. I've only recently released my name to the public.  --Bluefox Phoenix Lucid
 * FIGHT THE POWER!!!1!1!!!!11! FUCK YOU I WON'T DO MY HOMEWORK! as the band sang. No, but it has helped form my opinion of him - David Gerard 22:10, 16 Jul 2004 (UTC)
 * Now you're just being childish. --John Moser 05:17, 17 Jul 2004 (UTC)
 * He also says, "also tell him that i don't want to get pax into the kernel," which is noted in the article --Bluefox Phoenix Lucid
 * Object. There's been some good work on this article, and its improved loads. I particularly like the "Address space layout randomization" diagrams. However, I still think there's a few problems: 1) The "History" section is currently just a snippet from a HISTORY log file; could we rework this into an actual narrative paragraph? It would also be useful to have some dates in the lead section, too. 2) What's a ret2libc attack? 3) Do we know why it's not advocated for Kernel inclusion at this time? Does it need further development? 4) What other patches are available that do the same work as PaX? 5) How effective is PaX at preventing shellcode and "ret2libc" attacks? Completely? Mostly? — Matt 00:42, 20 Jul 2004 (UTC)
 * I'll do quick answers for now, back to the article later. --John Moser
 * The snippet from the history logfile is a primary source, I thought that would be nice in leui of a wordy paragraph about how old PaX is.
 * Dates in the lead section. You mean the section before Section 1, right?
 * ret2libc hasn't been written; but the term basically means, "Return To libc." The idea is that you overflow a buffer, write the address of, say, mprotect (hence the restrictions to mprotect) or memcpy (nasty idea:  memcpy repetedly to call memcpy and cause an infinite loop or data corruption) to the return address.  When the function exits, that function is called.  This is not injecting code.
 * The PaX Team does not wish to advocate. I believe they have their own reasons; but the most I've heard is something about it only working on a handfull of architectures (see NX) instead of *ALL* architectures (see every arch Linux supports).
 * Try "See Also," you'll see Exec Shield. That's only similar, though.
 * Shellcode/code injection, completely with full restrictions. Ingo Molnar (author of Exec Shield) repetedly states in e-mail that PaX is "finegrained protection;" rather than just supply an NX bit, it supplies a policy that basically ammounts to, "You will not have any memory executable after it's been writable.  This is not negotiable."  This policy removes the possibility of executing any memory that can't be guaranteed to have never been writable in the life of the process, which is essential to code injection.  The restrictions disallow W|X as well as adding PROT_EXEC (aka 'X') where it didn't previously exist.  Logically, this is 100% effective UNLESS the attacker can create a shared library and then mmap it in with executable permissions (if he can, he's good).
 * The "Executable space protections" section is now clearer on this. It explains the policy on memory that PaX implements, and leads the reader to the conclusion (which is also handed to them) that code can not be injected into the program. --John Moser 07:33, 21 Jul 2004 (UTC)
 * As for ret2libc attacks, you have to find some odd way to map out the executable space remotely to succeed, or else have God on your side, severely. If you have local access, there's /proc/(pid)/maps; but there's a patch that blots out all the useful information from THAT as well.  Unfortunately, this patch "doesn't belong in PaX" :)  Interestingly enough, if the attacker can't find various libc functions to do a ret2libc attack, he's pretty much scrsewed on the above idea of creating a shared lib and mmaping it in.
 * Object. After reading the article, I can't tell if PaX has anything beyond emulation of the NX bit.  The intro seems to say it also marks program memory as non-writeable. Is that different from the NX bit?  How? How does PaX compare to the other NX implementations like W^X? and Exec Shield?  Also, understanding of one of the major features of PaX as you have written it is dependent on knowing what a ret2libc attack is and even what ret2libc itself is. - Taxman 01:09, Jul 20, 2004 (UTC)
 * PaX, as stated above, implements a finegrained memory protection policy which goes beyond the other two. The point of PaX isn't to just add an NX bit; it's to keep little 12 year old bastards who think they're l33t because they can download some bash script and crash your webserver OFF your computer.  PaX has an effect even if there already is an NX bit, as indicated by PAGEEXEC:  "PAGEEXEC uses or emulates an NX bit."  I guess I should repeat that it uses a hardware NX bit if available.  I'll have to mention this in the article I guess. --John Moser 06:53, 21 Jul 2004 (UTC)
 * The "Executable space protections" section is now clearer on this; it's not a direct answer, because I want to stay away from "PaX Is God, ES and W^X suck" on the article. --John Moser 07:33, 21 Jul 2004 (UTC)
 * That kind of advocacy is not what is called for. But a concise section mentioning the basic differences between the approaches is fairly critical to the article. How is PaX "beyond the other two"? We are after all talking about approving this as one of Wikipedia's best articles and that should be a pretty high standard. - Taxman 20:08, Jul 21, 2004 (UTC)
 * Ingo Molnar points out in an e-mail conversation that on i386, the emulation ("approximation") tracks the upper code segment limit, and that mprotecting a high memory address (the stack) takes away ALL protections on lower memory. Also, he notes that PaX is more fine grained.  In short, I can't really do it without pointing out that PaX is simply more secure.  Molnar says that Exec Shield breaks less; but really, the toolchain has to mark binaries with PT_GNU_STACK/HEAP (we can make the toolchain do this for PaX, too) to provide a by-default nonexecutable stack.  Very little breaks, under either situation.  When things break under PaX, someone (the person writing the Makefiles for the apps, the distro provider, or the system administrator) has to mark the binaries with chpax and/or paxctl.  --John Moser 04:33, 22 Jul 2004 (UTC)
 * It can be noted that PAGEEXEC uses the same technique now as Exec Shield, as a PERFORMANCE BOOST; and then falls back to the original, high overhead method under situations where Exec Shield would lose protection. SEGMEXEC I still (unoficially) measured at 0.6% scalar overhead.  Again, I'm basically saying, PaX is more secure and accurate than ES, which basically means that ES sucks (from a security standpoint).  --John Moser 04:33, 22 Jul 2004 (UTC)
 * OK, there's a new section added before the History section. --John Moser 05:43, 22 Jul 2004 (UTC)
 * All that is good stuff. Still nothing on W^X and whether PaX offers anything that isn't in OpenBSD by default, or at least how the approach differs and advantages/disadvantages. For a patch that is not in the main kernel and no likelihood of it, you've set a high bar for what the article needs to cover in order to be featured. Good work so far though.  Just try not to get frustrated at criticism of your article.  It is what can make it a great article. Besides, I'm not asking for 5 paragraphs.  One or two concise ones would do. - Taxman 22:34, Jul 22, 2004 (UTC)
 * Heh, gimme a break here man. :)  W^X is OpenBSD, PaX and ES are both Linux.  I think trying to compare with W^X may be a little out of scope; Exec Shield could actually be viewed as a competitor of sorts, whereas W^X could no more compete with PaX than PaX could compete with Windows XP SP2's NX code.  Also, W^X and Exec Shield are similar technologies; but I know even less particulars about W^X than about Exec Shield (which I gathered my data about over e-mails with Ingo Molnar).  --John Moser 22:54, 22 Jul 2004 (UTC)
 * What a ret2libc attack is is outside the scope of the article. I don't define shellcode or virtual memory or anything else.  The article doesn't exist for ret2libc?  I can write a stub, but that's it.  --John Moser 06:53, 21 Jul 2004 (UTC)
 * That stub is fine, we just need something in that case. As I look at it again, the lead sentences in What does PaX offer does give the gist of what ret2libc attacks are all about. - Taxman 20:08, Jul 21, 2004 (UTC)

suggested dab improvement
jm, References in the article to system calls or library calls might be well if they were set off typographically. I suggest that they be put into a monospaced typeface, which is a sort of standard for executable code in the book design world. I understand this will be a bit of work, but with an article of this technical nature, everything that can help the reader's mind get around the material is worthwhile. In fact, that's the writer's burden regardless of the article. Anyway, I thought I pass on the thought. ww 13:34, 23 Jul 2004 (UTC)

Monospacing
Sure, how do you do monospacing?

Also, nice with the clarity; although I need to keep up behind you for things that you keep getting wrong or making bad grammar out of :p It's really helpful despite the rough edges though.

--John Moser 01:25, 25 Jul 2004 (UTC)

 * jm, Sorry about errors. I've been trying for conceptual clarity not absolute precision, as is evident. As for grammar, I trust (fervently hope, really) that they're typos. As for monospacing, it's something like (from memory now...) stuff . A look at one of the programming examples (eg, sort algorithms) will betray the trick exactly. ww 19:12, 26 Jul 2004 (UTC)

Impact on performance ?
I saw you request for peer review. I kind of remember that some programmers use (or used ?) self-modifying programs to improve the performance of critical codes. I guess that this would be impossible with PaX. Shouldn't it be discussed in the article ? Or is it just an old technique that nobody uses anymore ? Pcarbonn 19:21, 28 Jul 2004 (UTC)
 * Pcarbonn, Some languages allow self-modifying code (eg, changes in calling parameters, jump sequences, etc) but the dangers inherent with humans using such techniques has made such languages far less popular than they used to be in former times (when dinosaurs roamed the machine rooms). Some hardwae architectures (eg, at lease one early HP series) depended on self modifiying object code as well; if I recall correctly, the subroutine mechanism worked that way on those machines. The problem is that it's hard enough to get non mutable code working right; changing code on the fly is much trickier. The position that such code is more efficient (in time or resources) is no longer tenable. Memory is cheap (size, cost, power consumption, ...), and easily available (cost, power consumption, ...) processor speeds are such that such arguments rarely make economic sense anymore.
 * PaX makes the assumption (at the operating system memory management level) that some areas in memory can be known at process setup time (and later on as memory is assigned and freed) to be read only for some process(s), and that preventing such access by others improves system security. Given the ubiquity and persistence of malware and malware writers, this is a sensible apprehension. A process remains free, under PaX (as I understand the intent) to keep code in a read/write portion of its assigned memory and self-modify at will. If it goes west and tries to scribble where it shouldn't, the OS gets told and kills it; that your code did such a thing is your problem -- back to the debugger! The memory model used by most modern languages makes self modification (ie, doing exotic things with pointers) difficult when programs written in those langauges are running under PaX type supervision, but that's not really a PaX level issue; it's trying to keep the operating system from crashing and programs (including malware) from interfering with each other. You weren't supposed to be doing that sort of thing anyway, there being no language support for it in most cases.
 * Thus, the efficiency hit you envision isn't an issue for programs written in most modern languages. PaX imposes no program execution time overhead and little program setup time overhead, as I follow it. Its main running time overhead load is at the kernel level, and resource overhead lies in using a little memory to keep track of its charges. A program written in a self modifying language whose runtime package is willing to work in a PaXified environment ought not to even notice.
 * In general, if you want maximum run time efficiency (minimum execution time, minimum memory use) you should avoid general purpose operating systems altogether. But embedded programming like that isn't within the PaX brief at all. Maybe this clarifies things a bit? ww 16:56, 29 Jul 2004 (UTC)

 * PaX does the exact opposite of "A process remains free, under PaX (as I understand the intent) to keep code in a read/write portion of its assigned memory and self-modify at will." Code can not be in a read/write portion of assigned memory; you'll never be allowed to execute it if it's writable.  Only combinations of (read/write) or (read/execute) are allowed; (execute) also cannot be added if it is not already set on a page.  Thus, code can never self-modify.  Programs that try to self-modify with PaX restrictions in place are terminated immediately.
 * PaX does not protect processes from other processes; it protects them from themselves. It'd be comparable to if a night patrol walked around your neighborhood after say 10pm and made sure to lock your front door and roll up your car window and lock your car doors if you forgot to.  The times when this breaks programs would be comparable to when you leave your keys in your car.   It tries damn hard to stay out of your way, just don't do anything broken.
 * PaX will recognize trampolines, and "emulate" them by some method unknown to me. Short version, it just does.  If you want to know how, go read the docs--which the article links to because it's not made to go into the deep technical aspects of PaX, more just to touch the surface.  It won't allow blocks of code to be generated at runtime (like Java); Executable space protections pretty much makes this clear (esp. paragraph 4).
 * As for performance, there are no current official measurements. I got 0.67% (I think it was 0.67, I know it was 0.6 something) measured on x86 with a k7 Athlon XP with SEGMEXEC.  This is <1%, so it's low; it's also a scalar (it's a percentage, pretty CPU independent), so it's the same everywhere.  PAGEEXEC used on systems supporting HW NX would be pretty much effectively 0%; it's variable, but a trick noted in the PAGEEXEC segment brings it down to below SEGMEXEC's overhead on x86 in many situations.  When this trick fails, the overhead can rocket up to 5%, 20%, whatever, high high levels.
 * --John Moser 23:05, 29 Jul 2004 (UTC)
 * Clearly we see here a limitation in my understanding of PaX operation. I apologize for getting inverted on this one. However, as self-modifying code is generally thought (and experience shows) to be a Bad Thing, Pax's actual behavior (as stated by jm above) is sensible however much I missed something. Sorry about that. ww 14:00, 30 Jul 2004 (UTC)
 * Ah, good, you understand now. That means my work here is done :)  --John Moser 00:51, 2 Aug 2004 (UTC)

Featured Article!!! :D
This page is now a Featured Article!

Special thanks go to all of those who objected at the first FAC run and those who contributed, including Matt Crypto, Raul654, Ww, Taxman, Kate, Goplat, Timwi, David Gerard, and the rest of you who helped that I may have missed. Although I undertook getting this article up to FA status as a personal goal, it could not have been done without the input, clarity, simplification, and spell checking of the Wikipedia community.

Special thanks also goes to The PaX Team for looking over the article and checking for accuracy several times. It should be noted that there hasn't been an examination by them since the last bits of deep technical information were added (although the changes since then are supported by the information already gathered, or are not strongly technical); if something turns out to be inaccurate-- which should not be the case, but we are all human-- the fault would not lay on them. :)

Again, thanks to you all for your contributions; now I don't have to spend 10 hours explaining PaX to newbies :D

--John Moser 06:31, 11 Aug 2004 (UTC)

Request for references
Hi, I am working to encourage implementation of the goals of the Verifiability policy. Part of that is to make sure articles cite their sources. This is particularly important for featured articles, since they are a prominent part of Wikipedia. The Fact and Reference Check Project has more information. If some of the external links are reliable sources and were used as references (as I believe is the case with this article), they can be placed in a References section too. See the cite sources link for how to format them. Thank you, and please leave me a message when a few references have been added to the article. - Taxman 19:39, Apr 22, 2005 (UTC)

Dead link
During several automated bot runs the following external link was found to be unavailable. Please check if the link is in fact down and fix or remove it in that case!

 * http://lists.netsys.com/pipermail/full-disclosure/2005-March/032240.html
 * In PaX on Mon Jul 17 14:41:55 2006, Socket Error: (110, 'Connection timed out')
 * In PaX on Thu Jul 27 00:36:42 2006, Socket Error: (110, 'Connection timed out')

maru  (talk)  contribs 04:36, 27 July 2006 (UTC)

Orders of magnitude
PaX says On 32-bit systems, this amounts to 16 orders of magnitude; that is, the chances of success are recursively halved 16 times.. If an amount is halved 16 times it gets 2^16 = 65536 times smaller, which is 5 orders of magnitude, not 16. Orders of magnitude states that sometimes powers of 2 are used instead of powers of 10, but that's so uncommon that in my opinion "65536 times" should be used instead. // Duccio (write me) 23:01, 24 August 2006 (UTC)

On Portal:Free software, PaX is currently the selected article
Hopefully Portal:Free_software can attract some people here to help improve the article so that it doesn't lose its featured article status. For one thing, I recommend that people add references to this article. It will remain on the portal for a week or so. The previous selected article was Emacs. Gronky 23:02, 11 June 2007 (UTC)

 * Well, I can't say it helped much. Anyway, the selected article has moved on again and is now OpenWrt. Gronky 15:39, 20 June 2007 (UTC)

Data execution prevention
Am I right to think that PaX's executable space protection is analogous to Windows SP2 and later's data execution prevention feature? Would it be relevant to mention this in the article? RW 02:57, 9 July 2007 (UTC)

Needs references
This article's only reference is the documentation of the subject, with no inline citations. Is anyone interested enough in this article to improve it to the current featured article standard?  Pagra shtak  01:06, 27 October 2007 (UTC)

Attack against PaX requiring brute forcing only 16 bits (up to 20 maximum)
On the Effectiveness of Address-Space Randomization demonstrates an attack on PaX ASLR from 2004 that requires brute forcing 16 bits (with an upper bound of 20 bits) of randomness for systems with 32-bit address spaces. Probably worth a mention in the article, but I don't know how future work on it turned out.

Swolchok (talk) 22:22, 27 January 2009 (UTC)

External links modified
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I have just added archive links to 1 one external link on PaX. Please take a moment to review my edit. If necessary, add after the link to keep me from modifying it. Alternatively, you can add to keep me off the page altogether. I made the following changes:
 * Added archive http://web.archive.org/web/20070926222018/http://packetstorm.linuxsecurity.com/0503-exploits/paxomatic.c to http://packetstorm.linuxsecurity.com/0503-exploits/paxomatic.c

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External links modified
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Notability?
As grsecurity was deleted too, is this single patch from that patchset any more notable than the patchset itself? --ilmaisin (talk) 22:57, 19 August 2021 (UTC)

title: Talk:PaX


text:
Pony car

Pony car is an American car classification for affordable, compact, highly styled coupés or convertibles with a "sporty" or performance-oriented image. Common characteristics include rear-wheel drive, a long hood, a short decklid, a wide range of options to individualize each car and use of mass-produced parts shared with other models. The popularity of pony cars is largely due to the launch of the Ford Mustang in 1964.

There is much debate among enthusiasts about the exact definition of a pony car, and what differentiates the vehicle from a muscle car. The general consensus is that pony cars are smaller and more refined than muscle cars. A few intermediate-size vehicles, such as the Dodge Challenger, may be considered to belong to both categories.

In 2024, the Ford Mustang became the last remaining pony car still in production. The Challenger and the Camaro ended production in 2023; though the Camaro's final model year is 2024.

1960–1963: Predecessors

In the early 1960s, Ford, Plymouth, and AMC began noticing the rising interest in small, sporty cars, and the increasing importance of younger customers. In order to convince the management of Ford to approve a small, sporty car for production, the Budd Company built a prototype two-seat roadster called the XT-Bird. The XT-Bird was built using the compact car chassis of the Ford Falcon with a modified 1957 Ford Thunderbird body. Ford rejected the proposal, preferring to design a four-seat sporty car instead which would expand its sales volume.

The Budd Company then approached American Motors Corporation (AMC) with the Budd XR-400 prototype, which was based on a 1962 AMC Ambassador two-door with a shortened chassis and the body moved 16 in rearward to allow for a longer hood (bonnet). The automaker's "management expressed interest in a new car with a sports flair" and work on the AMC Rambler Tarpon, a 2+2 coupe with an elongated fastback roof, began in early 1963.

Examples of production cars that included sporty and youthful appeal were the 1960 Chevrolet Corvair. Initially positioned as an economy car, the Corvair's plusher-trimmed and sportier Monza model sold around 144,000 units by 1961. The Corvair Monza's bucket seats and floor-mounted transmission shifter started a trend toward these features being offered in cars ranging from compacts to full-size cars. Competing models inspired by the Corvair Monza included the Ford Falcon Futura and Futura Sprint models and the Rambler American 440-H and Rogue models. Most sporty compacts were powered by the same economical six-cylinder engines as their more mundane platform counterparts, but in some cases, optional V8 engines were available along with four-speed manual transmissions.

1964–1966: Initial pony cars released
The first pony car to be released was the Plymouth Barracuda, which went on sale on April 1, 1964 (two weeks before the Ford Mustang). The Barracuda was released as a fastback coupe, based on the platform of the Plymouth Valiant compact car. Chrysler's precarious financial situation meant that there was a limited development budget for the Barracuda, which led to a compromised design. The Barracuda was criticized for having insufficient distinction from the Valiant and the styling drew mixed reactions. As a result, Barracuda sales were a fraction of the Mustang's.

At the Ford Motor Company, executive Lee Iacocca had commissioned marketing studies that suggested that if a unique-looking sporty car could be offered at an affordable price, that the car would find many buyers. Therefore Ford continued development of a sporty 2+2 car based on the Ford Falcon platform, leading to the launch of the 1965 Ford Mustang on April 17, 1964. The Mustang was available as a two-door coupé and convertible, and had a unique "long hood, short deck" appearance. In its base specification, the drivetrain was typical of an economy car: a 170 cuin six-cylinder engine with a three-speed manual transmission. The US$2368 base price included bucket seats, carpeting, floor shifter, sport steering wheel, and full-wheel covers. However, options such as V8 engines, a four-speed manual gearbox, air conditioning, and power steering could increase the price by up to 60%, which made such versions very profitable for Ford.

The Mustang was an enormous success, with first-year sales forecasts of 100,000 units being shattered on the first day, when Ford dealers took orders for 22,000 vehicles, forcing the company to shift production mid-year. The extended model year sales totaled 618,812 Mustangs. The Mustang broke all post-World War II automobile sales records, "creating the 'pony car' craze soon adopted by competitors."

The 1965 Mustang provided the template for the new class of automobiles. The term "pony car" to describe members of its ranks was coined by Car Life magazine editor Dennis Shattuck. The characteristics of a pony car were defined as:
 * A sporty compact car for the masses, that could carry four people
 * Long hood, short deck profile, and "open mouth" styling
 * Affordable base price (under US$2500 – in 1965 dollar value)
 * Wide range of options to individualize each car
 * Manufactured using mass-produced parts shared with other models
 * Youth-oriented marketing and advertising

Many pony cars were produced with economical six-cylinder or small V8 engines and although powerful engines and performance packages were offered, the majority were sold with six-cylinder engines or relatively small V8 engines. The high-performance models saw limited sales and were largely limited to drag racing, road racing, or motorsport homologation purposes.

1967–1970 Segment expands
Initially, General Motors believed that the restyled 1965 Chevrolet Corvair (a rear-engined compact car) would be an adequate challenger for the Mustang. However, once GM realized that the Corvair was doomed, the more conventional Nova-based Chevrolet Camaro was introduced for the 1967 model year built on the new GM F-body platform and used a conventional front-engine layout. A few months later, the Camaro-based Pontiac Firebird was introduced.

The Mustang was redesigned for the 1967 model year and became the basis for the upscale Mercury Cougar on a longer wheelbase.

American Motors introduced its first pony car in 1967 with the AMC Javelin. The car was described as a "roomy, comfortable, peppy and handsome example of a so-called pony car, the type of automobile that's showing up more and more on US highways."

In 1969, the Dodge Challenger joined the already crowded pony car segment. The Challenger was essentially an enlarged Barracuda.

The pony car market segment was maturing and all four domestic automakers were building versions of the long hood/short deck template that Ford had developed. The term pony car applied to all versions of these nameplates, from base models to the high-performance muscle car models, developed in league with factory supported racing to gain a marketing edge. The competition between the manufacturers was so fierce that the introduction and rollout of the Trans-Am Series from 1966 to 1972 is described as a battle in "The Pony Car Wars".

While sales were strong throughout the end of the 1960s, pony cars' greater value was in generating brand loyalty, particularly among the crucial youth market. In 1970 Car and Driver reported that while very few pony car drivers bought a second, around 50% purchased another model from the same manufacturer. Even so, by as early as 1969 sales were beginning to slide, dropping to 9% of the total market from a peak of 13% in 1967.

Directly inspired by the Ford Mustang, Ford of Europe began production of the Ford Capri in 1968 (using the Cortina MkII platform and driveline and a few components from the Escort), while GM Europe introduced the Opel Manta and Vauxhall Firenza. In April 1970, the Capri began to be imported from Europe and was sold in Lincoln-Mercury dealerships.

The success of the Mustang also inspired the creation of the Toyota Celica compact coupe, which was released in 1970, while Toyota had earlier introduced the 1967 Toyota 1600GT 2-door hardtop and installed a DOHC I4 cylinder engine with dual carburetors and a 5-speed manual transmission. Like the Mustang, the Celica was built using the platform of an economy car; although the Celica was 23 in shorter than the Mustang and did not offer a V8 engine. Several Japanese automakers sold compact coupes in the United States as smaller competitors to pony cars. However, no Japanese manufacturer produced a pony car.

1971–1975: Larger cars, declining sales
As with many automobile redesigns, each subsequent generation of the pony cars grew larger, heavier, costlier, and more comfort-oriented. This trend towards larger and more comfort-oriented pony cars was also influenced by many buyers in the late 1960s and early 1970s purchasing optional equipment and models with higher prices. Examples of the increasing size and weight of pony cars are:
 * The 1970 Dodge Challenger was only slightly smaller externally than its Dodge Coronet stablemate, an intermediate-sized four-door sedan. The Challenger was less than 200 lb lighter than a typical intermediate sedan.
 * The 1971 AMC Javelin was 191.8 in long, which is 10 in longer than the 1965 Ford Mustang.
 * The 1973 Ford Mustang was 8.5 in longer, 5.9 in wider, and over 600 lb heavier than the original 1965 Mustang.

Big block V8 engines became available in pony cars, which increased straight-line performance but underscored the limitations of the suspension, brakes, and tires. The six-cylinder and lower-specification V8 engines struggled with the increased mass of the pony cars.

By 1970 buyers were moving away from the pony cars, either toward smaller compact cars or the more luxurious personal luxury cars. The pony car market was also hindered by high insurance rates and increased restrictions on performance cars. In the following years, power outputs of the performance models began to erode as a result of stricter vehicle emissions controls. By 1972, small imported sports cars were increasing in popularity, and the domestic pony cars were not selling well. Industry observers believed that the Chevrolet Camaro and Pontiac Firebird might be discontinued after the 1973 model year.

The 1973 oil crisis left the large and heavy pony cars out of step with the marketplace. The Mustang, which had grown to become an intermediate-sized car and alienated buyers, was downsized for its second-generation; this 1974 Ford Mustang II was marketed as a fuel-efficient model with luxury or sporty trim packages. Inspired by smaller imported sporty cars such as the Toyota Celica and Ford Capri, the new Mustang II was unveiled a few months prior to the 1973 oil embargo. Ford "decided to call it Mustang II, since it was a new type of pony car designed for an era of high gas prices and fuel shortages." To compete with these new sporty subcompacts, General Motors introduced the 1975 Chevrolet Monza and its badge-engineered variants. GM's original pony cars (the Chevrolet Camaro and Pontiac Firebird) were almost canceled, but remained in production.

Chrysler Corporation did not downsize its pony car models, but instead discontinued the Dodge Challenger and Plymouth Barracuda after the 1974 model year. The AMC Javelin was also canceled after 1974. The 1974 Mercury Cougar—originally designed as an upscale version of the Ford Mustang—left the pony car segment, as the vehicle was upsized and marketed in the personal luxury car segment.

1976–2004: Resurgence of popularity and performance
The popularity of pony cars increased in the late 1970s with examples appearing in movies and TV programs like the Pontiac Firebird Trans Am in Smokey and the Bandit, the Pontiac Firebird in The Rockford Files and the Ford Mustang II Cobra II in Charlie's Angels. The "Z28" high-performance option for the Chevrolet Camaro had been discontinued after 1974, however it was resurrected for 1977 due to the popularity of the Pontiac Firebird Trans Am.

The 1979 Ford Mustang (third generation) was redesigned using the larger Ford Fox platform. The redesigned Mustang also formed the basis of the Mercury Capri (second generation), which replaced the European-built first-generation and was now available with a V8 engine.

Chrysler Corporation, beset by financial problems, did not revive the pony car, instead offering smaller coupes such as the Dodge Daytona and Chrysler Conquest (a badge-engineered Mitsubishi Starion) in this market segment.

American Motors Corporation remained absent from the pony car segment, however the 1979 AMC Spirit subcompact was marketed as a competitor to the hatchback versions of the Ford Mustang. The Spirit was available with four-cylinder, six-cylinder, or V8 engines, and the model range included sporty "GT" and "AMX" models. In 1982, the Spirit GT became America's first pony car with a 5-speed manual.

In the early 1980s, concerns about fuel economy prompted Ford to seriously consider replacing the Mustang with a smaller front-wheel drive model (which eventually appeared as the Ford Probe instead). The Chevrolet Camaro and Pontiac Firebird escaped a similar fate with General Motors' front-wheel drive "GM-80" program canceled late in development. Emissions and fuel economy concerns also led the 1982 Chevrolet Camaro and Pontiac Firebird to be available with four-cylinder engines for the first time.

The introduction of fuel-injection on V8 engines in the mid-1980s—such as the Ford "5.0" engine (available in the 1986 Ford Mustang) and the General Motors "LB9" engine (introduced in the 1985 Chevrolet Camaro IROC-Z and Pontiac Firebird Trans Am)—benefitted the pony cars with increased power and fuel economy. However, declining sales and the growing popularity of light trucks and sport utility vehicles ultimately led to the Firebird and Camaro being discontinued after 2002, leaving the Mustang as the only remaining American-built pony car until the 2008 Dodge Challenger was introduced.

2005–present: Retro-style revival

Since the 1980s, the dilemma facing car manufacturers in offering pony cars is the lack of mass-produced automobile platforms to use as a basis for building them. Unlike the mid-1960s, the majority of modern compact cars are front-wheel drive with four- or six-cylinder engines, and engineering a dedicated rear-wheel drive performance vehicle platform specifically for a pony car is an expensive proposition.

The 2005 Ford Mustang (fifth generation) was the sole remaining pony car at the time of its introduction. The success of the Mustang-inspired the 2008 Dodge Challenger (third-generation) to be introduced, followed by the 2010 Chevrolet Camaro (fifth generation). Unlike previous pony cars, the Challenger and fifth-gen Camaro were built on the platforms from full-size cars. The Mustang and Camaro were sold in a coupe and convertible body styles, whereas the Challenger was sold only as a coupe.

The next generation of pony cars consisted of the 2015 Ford Mustang (sixth generation) and the 2016 Chevrolet Camaro (sixth generation) in 2015. The Mustang was the first pony car with independent rear suspension, a turbocharged four-cylinder engine, and right-hand drive required for specific export markets. The sixth-generation Camaro was downsized from a full-sized platform to a mid-sized platform more in line with its traditional size.

The first all-wheel drive pony car was the V6-powered 2017 Dodge Challenger GT.

The seventh-generation Mustang will debut in 2024. The new generation is very similar to the sixth generation in size, configuration, and options.

The sixth-generation Camaro will be discontinued at the end of the 2024 model year. However, Chevrolet has stated, "This is not the end of Camaro's story."

The current Dodge Challenger and Charger are expected to be discontinued after the 2023 model year, and replaced with a new, fully electric, retro-styled Charger Daytona, which will most likely be a 2-door coupe similar to the current Challenger. Ford plans to debut the fully electric eighth-generation Mustang in 2028, and GM is considering an electric Camaro coupe as well.

Vehicles

 * AMC Javelin (1968–1974)
 * Chevrolet Camaro (1967–2002; 2010–2023)
 * Dodge Challenger (1970–1974; 2008–2023)
 * Dodge Charger (2024–present)
 * Ford Mustang (1965–present)
 * Mercury Capri (1979–1986)
 * Mercury Cougar (1967–1973)
 * Plymouth Barracuda (1964–1974)
 * Pontiac Firebird (1967–2002)

Motor racing
The 2000s pony car revival also saw a renewed focus on motor racing, beginning with the NASCAR Xfinity Series (then called the "Nationwide Series") in 2010, where the Dodge Challenger and Ford Mustang silhouette racing cars were introduced. Modern pony cars have also competed in the Rolex Sports Car Series, SCCA World Challenge, and the Michelin Pilot Challenge. The Ford Mustang and Chevrolet Camaro have been homologated for Group GT3 racing, and the Ford Mustang was homologated in 2017 for SRO GT4 racing. Pony cars like the Dodge Challenger, Ford Mustang, and Chevrolet Camaro are still used today in the NASCAR Pinty's Series.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Pony car


text:
Poets' Corner

Poets' Corner is a section of the southern transept of Westminster Abbey in London, where many poets, playwrights, and writers are buried or commemorated.

The first poet interred in Poets' Corner was Geoffrey Chaucer in 1400. William Shakespeare was commemorated with a monument in 1740, over a century after his death. Over the centuries, a tradition has grown up of interring or memorialising people there in recognition of their contribution to British culture. In the overwhelming majority of cases, the honour is awarded to writers.

In 2009, the founders of the Royal Ballet were commemorated in a memorial floor stone and on 25 September 2010, the writer Elizabeth Gaskell was celebrated with the dedication of a panel in the memorial window. On 6 December 2011, former Poet Laureate Ted Hughes was commemorated with a floor stone. On 22 November 2013, the fiftieth anniversary of his death, writer C. S. Lewis was commemorated with a memorial floor stone. The poet Philip Larkin was commemorated with a floor stone dedicated on 2 December 2016.

History
The first poet interred in Poets' Corner, Geoffrey Chaucer, owed his 1400 burial in the Abbey (in front of St. Benedict's Chapel) more to his position as Clerk of Works of the Palace of Westminster than to his fame as a writer. The erection of his magnificent tomb by Nicholas Brigham in 1556 (to where Chaucer's remains were then transferred) and the nearby burial of Edmund Spenser in 1599 began a tradition that still continues. The area also houses the tombs of several Canons and Deans of the Abbey, as well as the grave of Thomas Parr who, it is said, died at the age of 152 in 1635 after having seen ten sovereigns on the throne.

Burial or commemoration in the Abbey does not always occur at or soon after the time of death. Lord Byron, for example, whose poetry was admired but who maintained a scandalous lifestyle, died in 1824 but was not given a memorial until 1969. Even William Shakespeare, buried at Stratford-upon-Avon in 1616, was not honoured with a monument until 1740 when one designed by William Kent was constructed in Poets' Corner (though shortly after Shakespeare's death William Basse had suggested Shakespeare should be buried there). Samuel Horsley, Dean of Westminster in 1796, was said to have tartly refused the request for actress Kitty Clive to be buried in the Abbey:

"if we do not draw some line in this theatrical ambition to mortuary fame, we shall soon make Westminster Abbey little better than a Gothic Green Room!"

Not all poets appreciated memorialisation and Samuel Wesley's epitaph for Samuel Butler, who supposedly died in poverty, continued Butler's satiric tone:

Some of those buried in Poets' Corner also had memorials erected to them over or near their grave, either around the time of their death or later. In some cases, such as Joseph Addison, the burial took place elsewhere in Westminster Abbey, with a memorial later erected in Poets' Corner. In some cases a full burial of a body took place, in other, later, cases the body was cremated and the ashes buried. There are also cases where there was support for a particular individual to be buried in Poets' Corner, but the decision was made to bury them elsewhere in the Abbey, such as Edward Bulwer-Lytton. Other notable poets and writers, such as Aphra Behn, are buried elsewhere in the Abbey. At least two of the memorials (both to individuals buried in Poets' Corner – Rowe and Gay) were later moved to a location elsewhere in the Abbey due to the discovery of old paintings on the wall behind them. In 1936 the ashes of the author and poet Rudyard Kipling were interred.

Memorial types
The memorials can take several forms. Some are stone slabs set in the floor with a name and inscription carved on them, while others are more elaborate and carved stone monuments, or hanging stone tablets, or memorial busts. Some are commemorated in groups, such as the joint memorial for the Brontë sisters (commissioned in 1939, but not unveiled until 1947 due to the Second World War), the sixteen First World War poets inscribed on a stone floor slab and unveiled in 1985, and the four founders of the Royal Ballet, commemorated together in 2009.

The grave of Ben Jonson is not in Poets' Corner, but is in the north aisle of the nave. It has the inscription "O Rare Ben Johnson" (perhaps the original spelling) on the slab above it. It has been suggested that this could be read "Orare Ben Johnson" (pray for Ben Johnson), which would indicate a deathbed return to Catholicism, but the carving shows a distinct space between "O" and "rare". The fact that he was buried in an upright grave could be an indication of his reduced circumstances at the time of his death but it has also been suggested that Jonson asked for a grave exactly 18 inches square from the monarch and received an upright grave to fit in the requested space. As well as the gravestone in the north aisle of the nave, a wall tablet commemorating Jonson was later erected in Poets' Corner.

As floor and wall space began to run out, the decision was taken to install a stained glass memorial window (unveiled in 1994 in memory of Edward Horton Hubbard), and it is here that new names are added in the form of inscribed panes of glass. There is room for 20 names, and currently there are six names on this window, with the latest entry (Elizabeth Gaskell) unveiled on 25 September 2010. The memorial ceremonies often include guest speakers. In 1995, Oscar Wilde was commemorated in the window and those in attendance included Sir John Gielgud and Dame Judi Dench who both read extracts from his work.

First World War poets
The memorial in Poets' Corner, Westminster Abbey, to 16 Great War poets is a slate stone slab with the names of the poets inscribed on it. It was unveiled on 11 November 1985, the 67th anniversary of the Armistice. An additional inscription quotes Owen's "Preface":

My subject is War, and the pity of War. The Poetry is in the pity.

The † symbol indicates poets who died during the war.

Royal Ballet
The stone slab floor memorial to the four founders of the Royal Ballet was dedicated on 17 November 2009.

Elsewhere in the Abbey
Poets and writers commemorated elsewhere in Westminster Abbey, but not in Poets' Corner proper.

title: Poets' Corner


text:
User talk:Ivanf

Hello and welcome to Wikipedia!

Here are some tips to help you get started:

 * If you haven't already, please add your name to the new user log to let others know a little about yourself.
 * Read the article describing how to edit a page and feel free to experiment in the Sandbox.
 * When editing pages, use the preview button before submitting and try to fill in the summary box for every edit.
 * Eventually, read the Manual of Style and Policies and Guidelines.
 * If you need help, post a question at the Help Desk or ask me on my talk page.
 * Explore, be bold in editing pages, and, most importantly, have fun!

Good luck! Jrdioko

P.S. One last helpful hint. To sign your posts like I did above (on talk pages, for example) use the '~' symbol. To insert just your name, type (3 tildes), or, to insert your name and timestamp, use ~ (4 tildes).

title: User talk:Ivanf


text:
Legislative Assembly of the Northwest Territories

The Northwest Territories Legislative Assembly, or Legislative Council of the Northwest Territories (with Northwest hyphenated as North-West until 1906), is the legislature and the seat of government of Northwest Territories in Canada. It is a unicameral elected body that creates and amends law in the Northwest Territories. Permanently located in Yellowknife since 1993, the assembly was founded in 1870 and became active in 1872 with the first appointments from the Government of Canada.

Until 2014, the assembly was officially defined under federal law as "Legislative Council". However, under Northwest Territories territorial law, it was defined as "Legislative Assembly". The federal name was changed when the Northwest Territories Act was rewritten in 2014. Under different periods of its history it has alternated names.

Members of the Legislative Assembly are sworn in by the commissioner of the Northwest Territories.

Early history
The Legislative Assembly was first known as the Temporary North-West Council and was created in 1870. The first appointments to the council were made on December 28, 1872. The Temporary Council was dissolved in 1876 and a new permanent council was appointed and moved to the new capital of Fort Livingstone in 1876. The council moved to Battleford a year later based on the planned location there of the Canadian Pacific Railway.

The very first election to the Assembly would take place on March 23, 1881, as Lawrence Clarke was elected to represent the electoral district of Lorne. In 1883 the Assembly moved south to Regina based on amendments to the route of the railway. The first territory-wide election took place on September 15, 1885, known as the 1885 Northwest Territories election.

Three years later the first general election took place. All the voting members of the Assembly were elected for the first time, and an elected speaker took office. The Lieutenant Governor still had executive authority however and appointed and ran the cabinet. After the second general election in 1891 the first fully elected Assembly without any appointed members. The Assembly achieved Responsible Government for the first time in October 1897 as the Lieutenant Governor appointed Frederick Haultain as the first Premier to form a government. Robert Brett became the first Leader of the official opposition and party lines were roughly drawn based on Conservatives and Liberals.

The Haultain government lobbied for Government of Canada for provincial powers for the Northwest Territories. In response on September 1, 1905, the provinces of Alberta and Saskatchewan were created by Prime Minister Wilfrid Laurier out of the southern populated portion of the territories.

Court of law
The Northwest Territories Legislative Assembly served as the first court of law in the Northwest Territories from 1876 until the creation of the Supreme Court of the Northwest Territories in 1887. Appointed members of the council served as stipendiary magistrates would travel the territories and oversee legal cases when the Legislature was not sitting. In 1887 the Northwest Territories moved to a new system that assigned judges to judicial districts and separated the legal and judicial branches.

Ottawa
After the creation of Alberta and Saskatchewan, the remainder of the Northwest Territories was too sparsely populated by enfranchised voters to justify holding elections. The territory reverted to its confederation entry status. A new council was set up in Ottawa consisting of a Commissioner—the effective replacement of the Lieutenant Governor—and four appointed members.

Frederick White was appointed as the first Commissioner and did not recall the council to sit during his time in office. During this time, the Territories were run by the federal Department of Mines and Resources. The first session of the Council of the Northwest Territories took place in 1921. The council members were bureaucrats appointed from the Interior Ministry and were not resident citizens of the territory.

In 1939, the Yellowknife Administration District was created to provide services within 25 miles of Yellowknife. However, it was not until 1947 that John G. McNiven was appointed to represent the district. McNiven was the first member appointed to the council from north of the 60th parallel.

In 1951 the council held its first general election in 49 years. The fifth general election elected three members from the District of Mackenzie. The old council was completely dissolved and five members were appointed along with the three elected representatives.

The council gradually gained more powers back from the federal government as the population in the territory grew. In 1967 the Carrothers Commission moved the territorial capital from Ottawa to Yellowknife and for the first time elected members represented all parts of the territories. In 1975 the Legislative Assembly became fully elected, and the first elected speaker since 1905, David Searle, presided over the Assembly.

Consensus government
Commissioner John Parker gave up his powers of running the executive council and appointed George Braden as leader of the government and the first premier since 1905. The model of responsible government that was used this time around was known as consensus government. The executive council or cabinet forms government while all the regular members form an unofficial opposition.

The modern consensus government model is inherently non-partisan and serves effectively as a constant minority government. The legislature uses this model up to the current day; the same model of government is also used in the Legislative Assembly of Nunavut, although Canada's other territorial legislature, the Legislative Assembly of Yukon, uses a traditional partisan politics model.

The consensus government model has received criticism on various grounds, including that it hampers long-term political and economic development in the territory because the lack of political parties mean that there is no mechanism to carry over a political agenda from one assembly to the next; that it complicates the ability of less wealthy citizens to serve in the assembly because the lack of political parties means that election candidates must raise all of their campaign funds on their own; that it prevents the voters from being able to demand or vote for systemic change, since there is no mechanism to replace an ineffective or underperforming government with another alternative; and that it hampers efforts to improve diversity in representation, such as the election of more women and ethnic minorities to the legislature.

In 2018, MLA Kieron Testart introduced an amendment to the territorial Elections Act to permit the introduction of party politics in the legislative assembly, but his motion received no support from other MLAs and was dropped. In 2019, he planned to organize a group of ideologically aligned MLA candidates in the 2019 Northwest Territories general election into a "Liberal Democratic" slate, but backed off of the plan after it was leaked to the press.

Assembly buildings

The building that has housed the Northwest Territories Legislative Assembly has changed many times since it was founded. The first building was the original Manitoba Legislature in Fort Garry. After the council moved to Fort Livingstone it was housed in the Swan River Barracks used by the North-West Mounted Police.

The first building built for the needs of the Assembly was NWT Government House in Battleford. That building also served as a residence for the Lieutenant Governor. In 1883 the Assembly moved to Regina. The Territorial Administration building was built to accommodate the growing Assembly and used until 1905.

After the creation of Alberta and Saskatchewan, the capital was moved to Ottawa and the council sessions took place in an office building on Sparks Street. When the council sessions returned to the territories, they were held in any infrastructure suitable as they traveled from community to community.

After the capital was moved to Yellowknife in 1967 a temporary site for the Legislative Assembly was used until the new Legislature building was finished in 1993. The design of the current Legislature building was created by Pin/Taylor Architects company from Yellowknife.

Current membership
The membership of the 20th Northwest Territories Legislative Assembly, was selected in the 2023 Northwest Territories general election on November 14, 2023. Each member represents one electoral district.

The territory has fixed election date legislation that ensures elections are held every four years on the first Monday in October.

The legislature since 1905 is a non-partisan body and all members run and sit as independents.

Cabinet Ministers
The seven ministers of the Government of the NWT are found in the Executive Council of the Northwest Territories.


text:
Talk:Dave Winer

Podcasting
If you guys undo one more change without providing some proof I'll report you. DAVE DID NOT INVENT PODCASTING.--Irelan12 (talk) 18:44, 1 May 2012 (UTC)
 * Hi - discussion is key - I suggest a read of WP:BRD - its a good way of working together - you make a B old edit and its R everted and you then Discuss - BRD - Please don't post in capitals, its considered shouting, thanks - You  really  can  18:48, 1 May 2012 (UTC)

Quit telling me what to do and stop adding incorrect statements. There are people who founded large companies that don't have this much talk about their blogs and fake claims of inventing things. You guys are being rediculous.--Irelan12 (talk) 18:51, 1 May 2012 (UTC)

Now, if you want any of those back, provide proof. --Irelan12 (talk) 18:57, 1 May 2012 (UTC)

 * Irelan, please calm down. We have discussed these questions at great length.  Winer's role in the development of podcasting is clear and well known. Winer’s role in developing and promoting EditThisPage is also well known. Both are clearly documented.  None of this is ridiculous, or even contested by the overwhelming consensus here.  Some questions of nuance may deserve discussion. Were other developers at Userland worth mentioning here?  Should more attention to these matters be paid at Userland's page?  But the outlines are clear.  Further, your tone seems less the civil -- and appears to be growing more agitated, not less, as suggested by your threat to "report you".

 * I'd also like to point out that the subject founded several very successful companies and did, in point of fact, play a central and crucial role in developing and popularizing outliners, podcasts, and outlines. Your insistence that these are "fake claims" is not supported by the historical record and, in themselves, raise some potential BLP issues.

 * In any case, I think I speak for a number of editors in asking that you not make further sweeping edits along these lines before discussing them, and obtaining a reasonable consensus, here. MarkBernstein (talk) 19:07, 1 May 2012 (UTC)

Writer Section
The "writer" section is clearly not worthy of being in the page. It is simply fluff meant to add credibility to the rest of the page. If you look at Steve Wozniak his personal site isn't mentioned, the same is true for other tech company heads.--Irelan12 (talk) 16:45, 26 April 2012 (UTC)

If no one objects to this, here, I will consider it approval to edit the page. Any undoing will be considered vandalism.--Irelan12 (talk) 16:56, 26 April 2012 (UTC)

 * strong objection. Winer was for many years a leading tech journalist. His journalism alone would make him notable in wikipedia terms. In addition, Winer's Scripting News was extremely important in forming weblog style, and in creating the now-familiar role of tech celebrity. (Please assume good faith and tone down the threats that "any undoing will be considered vandalism". By whom? Let's get along.) MarkBernstein (talk) 17:07, 26 April 2012 (UTC)
 * Mark, you certainly haven't wanted to get along in the past. He isn't a journalist at all. He has a personal blog that details his personal feels. His work for Hotwired is documented. I see no other tech company founders who's personal blog is listed in their article. All of this talk like, "important in forming a style and the father of", simply exists because I pointed out that he didn't invent the things this article claims he did. I have no objection to including a link to Scripting news, but a section about writing because he has a personal site? Come on.--Irelan12 (talk) 17:13, 26 April 2012 (UTC)

 * Some examples: Jakob Nielsen is directly comparable. John Gruber occupies a place today much like the one Winer occupied years ago. On Winer's role in the development of weblog style, see Scott Rosenberg, __Say Anything_ Scott_Rosenberg_(journalist).  MarkBernstein (talk) 17:39, 26 April 2012 (UTC)
 * Both of those people's personal sites are listed as links. Only companies are listed in the article.--Irelan12 (talk) 17:44, 26 April 2012 (UTC)
 * Analogies with other Wikipedia articles are irrelevant. There is one simple and compelling rationale for this section: Winer's writing is discussed in a non-trivial number of reliable sources, which are duly referenced in the section. ARK (talk) 19:40, 26 April 2012 (UTC)

Notability of Share Your OPML and Edit This Page
Also, Id like to get along, but some of this is obviously fluff and making some of the things hes done vastly more important than they were. Some of these share your OPML site type entries are for sites that were never popular and don't exist anymore. Bill Gates started a company before Microsoft, but its never got its own section. Lets be fair instead of promoting fluff.--Irelan12 (talk) 17:19, 26 April 2012 (UTC) For example, Editthispage.com was a Userland site, not Dave's site.--Irelan12 (talk) 17:22, 26 April 2012 (UTC)
 * Share your OPML was noted in the technology press at the time. The comparison with Bill Gates is spurious: Living Videotext created a new commercial product category and won a major industry award for one of its products. ARK (talk) 19:53, 26 April 2012 (UTC)
 * Editthispage and some of the ohter sites are Userland sites, not Dave's. You will leave untruths in the article and try to take away negative things that are clearly mentioned in a notable blog. Please quit editing this article as you have proven you can't do so with a clear mind. --Irelan12 (talk) 16:15, 27 April 2012 (UTC)
 * I agree with ARK, and I am not convinced by your arguments. Disclosure: though I was a Radio Userland user for a short time 10 years ago or more, I do not presently use any of Winer's software, nor do I know him personally. -- DaveSeidel (talk) 18:15, 27 April 2012 (UTC)
 * Winer never formalised corporate governance at UserLand -- it was understood that he was making the strategic and operational decisions on his own. It was certainly his decision to launch Edit This Page, and it was his decision to pump it up even in the absence of a business plan. So insisting on a separation between Winer the man an UserLand the company is mostly an exercise in splitting hairs.
 * I've added a reference from an O'Reilly book to the Share Your OPML section, which should establish its notability beyond reasonable doubt. ARK (talk) 18:48, 27 April 2012 (UTC)
 * That dosen't cut it, the site that is listed as a reference shows a screen shot that says Userland. Why is it so important to puff this article up? It was clearly a Userland product.--Irelan12 (talk) 19:05, 27 April 2012 (UTC)
 * UserLand was a small company that consisted of Dave Winer and whatever half-dozen-or-so programmers he was hiring at any one time. For most of its history, UserLand also depended on Winer to write the cheques that would keep the company going because revenue was negligible or inexistent. Winer was also the majority shareholder, so he wasn't accountable to anybody. The difference between Winer the man and UserLand the company amounts to a pointless quibble.
 * Again, this is a fluff piece. I have cited proof that Editthispage was a Userland product and you still refuse to remove it. — Preceding unsigned comment added by Irelan12 (talk • contribs) 17:45, 28 April 2012 (UTC)
 * It is common knowledge that EditThisPage was a UserLand site, there is no "proof" required. Nobody, however, finds your argument convincing that the circumstance is grounds for excluding EditThisPage from Winer's biography. DaveNet and Scripting News were UserLand sites at the time. ARK (talk) 19:38, 28 April 2012 (UTC)
 * If its common knowledge that Userland made it then your opinions don't matter. It should be removed according to the rules of Wikipedia. I thank you for admitting such.--Irelan12 (talk) 22:36, 28 April 2012 (UTC)

 * I see no reason to exclude a UserLand project from the page; the subject ran the company and was its primary software designer. MarkBernstein (talk) 00:31, 29 April 2012 (UTC)

Well I'm going to remove it. Your opinion is not important when it's a matter of fact.--Irelan12 (talk) 01:04, 29 April 2012 (UTC)

 * Why remove Edit This Page? It's been discussed here, and I think the consensus is clear that Edit This Page belongs on this page. Of course, if you'd like to improve the Userland page by discussing it there as well, that would be excellent! Why not think of some better ways to extend and improve this page? MarkBernstein (talk) 02:32, 29 April 2012 (UTC)
 * Only items that are true and referenced belong. Editthispage was created by Userland, it dosen't belong here.--Irelan12 (talk) 02:37, 29 April 2012 (UTC)
 * There are several broken links. We need to fix this to make sure the references are correct.--Irelan12 (talk) 23:56, 30 April 2012 (UTC)
 * Pretending to fix a broken link, Irelan12 has just made a bad-faith edit removing the Edit This Page section, overruling the view of the other editors in this thread. ARK (talk) 07:55, 1 May 2012 (UTC)
 * I have added two book references to the Edit This Page section, one of which explicitly identifies Winer as the "proprietor" of the service. ARK (talk) 10:13, 1 May 2012 (UTC)
 * EDITTHISPAGE WAS MADE BY USERLAND.--Irelan12 (talk) 18:44, 1 May 2012 (UTC)

Lawsuit and Cybersquatting
Quit undoing things and calling them vandalism. If the statements are true they can be here. Quit trying to edit out anything negative. You act like children. You do not own Wikipedia and can't delete things that you simply don't like.

Its nice that this page is protected every time someone adds something that isn't flattering to Dave Winer. I would like to see anyone argue that Gawker and the other sources are not apropriate. There is nothing wrong with the edits I made, the people here are simply biased and childish. If you can show that any of the things added are untrue, please discuss it here rather than simply trying to force people to do as Mr. Winer asks.(Irelan12)
 * Winer's alleged cybersquatting is not a matter of "truth" but of relevance. A minor squabble over a few domain registrations is simply too trivial to merit inclusion in this biography, even if a self-described gossip magazine and an adversarial blog chose to report it. The litigation over weblogs.com was apparently decided in Winer's favour, so the there is no reason to repeat the charges brought against him. ARK (talk) 00:37, 26 April 2012 (UTC)
 * ARK (talk) Your reasoning for not wanting the cyber squatting episode in the article, is that it is not flattering to Dave. The episodes got more attention in the media then most of the other things mentioned here. Also, the lawsuit's outcome has no baring on its merit. He was sued and I provided documentation. If you would like to include what the outcome was please do so. Simply editing my contributions is the vandalism you guys have accused me of. You are capable of adding what you want, so do so if you have references and please leave what it true in the article.--Irelan12 (talk) 16:28, 26 April 2012 (UTC)

 * I changed the section topic to a more neutral-sounding summary. I think this is probably a good idea for keeping everyone calm and civil.

 * I think good faith suggests that we should assume that ARK's edits are intended to improve Wikipedia, and civility suggests that we should not attribute motivations to other users. WIkipedia articles should be informative; they are not meant to be catalogs of every fact or occurrence, verifiable or not. Someone filed a lawsuit; they lost. This happens all the time for all sorts of reasons, and there's no clear reason to think this episode is significant.  Two businesses disagreed over exactly who owned what; the courts cleared it up. Happens every day. You, NIrelan, care about it, but I don't know why it matters to the general reader. MarkBernstein (talk)

I would like to propose the Cybersquatting section for removal as it does not meet the notability criterion. Moreover, the headline of the article cited for support should disqualify that article from consideration as a reliable source. ARK (talk) 19:59, 26 April 2012 (UTC)
 * Agree. DaveSeidel (talk) 20:44, 26 April 2012 (UTC)
 * Ark this just shows your bias, the cybersquatting section is based on a more reputable site than anything referncing the OPML part.--Irelan12 (talk) 16:15, 27 April 2012 (UTC)
 * The irrelevance you wish to include under Cybersquatting is still only supported by a potty-mouthed piece in a gossip rag. Its foul language is evidence that the piece didn't go through an editorial process. Normally on Wikipedia, editorial process is the baseline for a reliable source. ARK (talk) 20:49, 27 April 2012 (UTC)

 * Delete the section, keep OPML. It seems to me that we discussed the cybersquatting question some time ago and decided it was not sufficiently important to include. Is this not a WP:DEADHORSE? The question of separating Winer from UserLand is pointless; whatever its revenues and governance, UserLand was unquestionable an influential software developer and Winer was its software designer and architect. The Gawker piece is not a reliable source, and even if there were a reliable source -- there are surely court records -- the incident would not be notable. Businesses ask courts to decide who owns what all the time, and people do defensive domain registrations all the time as well.   MarkBernstein (talk) 21:00, 27 April 2012 (UTC)
 * +1. The horse does indeed stink to high heaven. -- DaveSeidel (talk) 21:36, 27 April 2012 (UTC)
 * Another obvious concern is Nirelan's conflict of interest: He was party to the incident he wishes to include in Winer's biography, and has previously failed to get the biography deleted in response to the incident. Here's the comment thread that triggered the hostilities in 2007. ARK (talk) 10:01, 28 April 2012 (UTC)
 * Ark Bestydevine or whatever her screen name is has contributed several things to this article and personally knows Dave. — Preceding unsigned comment added by Irelan12 (talk • contribs) 17:45, 28 April 2012 (UTC)
 * I'm going to remove the Cybersquatting section per WP:DEADHORSE (original discussion in 2007) ARK (talk) 18:44, 29 April 2012 (UTC)

BLP noticeboard
This article is now the subject of a thread on the BLP noticeboard: see Biographies of living persons/Noticeboard. —Tom Morris (talk) 19:54, 27 April 2012 (UTC)

 * Irelan12 has been blocked indefinitely as a sock puppet of Nirelan. ARK (talk) 18:51, 29 April 2012 (UTC)

 * Block logs: [Irelan12] [Nirelan] -- Irelan12 has been blocked for 48 hours. ARK (talk) 19:40, 1 May 2012 (UTC)

 * user:Irelan12 has been banned from Wikipedia after a discussion at the Wikipedia administrators' noticeboard. ARK (talk) 10:39, 2 May 2012 (UTC)

Neutrality questioned
This article has been nominated by an anonymous user to be checked for its neutrality. As the user offers no discussion of this nomination, I assume it can be ignored and the template should be removed. ARK (talk) 08:24, 14 October 2012 (UTC)

 * I agree. But isn't it interesting how quiet and trouble-free this page has been in the six months since one user was banned? MarkBernstein (talk) 17:37, 14 October 2012 (UTC)

 * I just read through all of the prior history of contention on this article. I understand the banned user's point, and am sympathetic. I also understand why it was problematic, in the context of Wikipedia. Wikipedia isn't intended to be a form of investigative journalism. Wikipedia cannot right grievous miscarriages of justice nor remedy unethical behavior by the subjects of BLP articles. Trying to do so wouldn't right the wrongs expressed by the banned editor(s), but rather, lead to defamation lawsuits against WP. That isn't helpful to anyone!

 * Be all this as it may, I found the article quite informative as it is now. I don't believe that a recording of the subject's voice is necessary. Otherwise, it is quite sufficient for me to see that the subject's background as a businessman is chronicled, sparsely but sufficiently. The same is true regarding the question of "Who invented RSS, RSS 1.0 and RSS 2.0, Aaron Swartz or DW?" and so forth. I am most grateful for the details regarding DW and Professor Jay Rosen's collaborative endeavors. The article is probably too lengthy, and fails to mention religious affiliation, marital status or offspring. If I were gratuitously trouble-making, I would initiate a squabble about whether the subject should be included in Category American Jews. I am not inclined toward that, not for now. --FeralOink (talk) 04:50, 28 July 2013 (UTC)
 * The inclusion of the subject's voice is not a matter of being "necessary" or not: it's a nice thing to have, like good photography and so on. A whole project run by User:Pigsonthewing and others was setup to collect these. Just because something isn't "necessary" doesn't mean we shouldn't include it if it is both interesting and doesn't fall foul of content policies. —Tom Morris (talk) 15:59, 31 March 2014 (UTC)

We've had the "POV check" for 5 1/2 months; it's time to delete it. MarkBernstein (talk) 23:57, 1 April 2014 (UTC)

Edits of this date
Calling for a little outside attention to the article. I came here today to find out the role of this individual in some technological advances. The article is rich with detail, but limited in its broader perspective, in part because it relies so thoroughly on news reports (which do not have the persecutive or go deeply enough to be actual best sources for WP historical statements), and then, as well, it relies on substantial material, sourced and unacknowledged, that derives from the title subject. For these reasons, I have called for a technology expert to see if some Winer sources can be replaced with third-party, scholarly, secondary sources, to buttress stated importance of his contributions and innovations.

In course of doing this, an effort was made to begin the process of checking and completing citation to standard, esp. URL-only citations.

As well, I have made more transparent the lack of sourcing of some material to Winer sources (adding tags to clear autobiographical statements), and as a matter of principle and policy, have removed a variety of external links that were embedded in the text (turning them into formal sources). An inexplicable external link to a blog, of Winer's father, was removed, because it was unclear what this source was intended to convey. (Perhaps the externally linked blog was the blog of the father; regardless, it was not properly placed as a source, and was not a valid source for the fact that the gentleman named was Winer's father.

As well, the general issue is explained in this way, to include the indirect: It is clear that Mr Winer has initiated and participated in many efforts, organizations, and companies. When these organizations and companies produce informational materials about Winer efforts, products, etc. these sources of information are still, inherently under the control of the title subject (while he is at the helm of the effort), and so these are not independent, third-party sources, as called for under WP:VERIFY. Hence, these also do not contribute the perspective that is most needed (and called for via the expert tag), for this article.

Otherwise, in lessor matters, I combined two overly short sections containing related career content categories, made a section title to be "Family background and education" as this is more standard for BLP articles, added a "Personal life" section, to end, as per standard for biographies,

Finally, the reason for the "third-party" and BLP refimprove" tags was simply this: there was a complete lack of third-party sourcing in the Early life… section, and most material there was unsourced. And as I scanned elsewhere in the article, I noted that this bad habit of inserting unsourced sentences had begun to occur, in this otherwise well-researched article.

It is best we keep to standard, and not let the article begin to drift to the addition of stray unsourced statements. People's opinions and stray thoughts are fine, but they are not encyclopedic.

That is all, Press on. Le Prof. Leprof 7272 (talk) 21:11, 17 March 2016 (UTC)

title: Talk:Dave Winer


text:
Biostratigraphy

Biostratigraphy is the branch of stratigraphy which focuses on correlating and assigning relative ages of rock strata by using the fossil assemblages contained within them. The primary objective of biostratigraphy is correlation, demonstrating that a particular horizon in one geological section represents the same period of time as another horizon at a different section. Fossils within these strata are useful because sediments of the same age can look completely different, due to local variations in the sedimentary environment. For example, one section might have been made up of clays and marls, while another has more chalky limestones. However, if the fossil species recorded are similar, the two sediments are likely to have been laid down around the same time. Ideally these fossils are used to help identify biozones, as they make up the basic biostratigraphy units, and define geological time periods based upon the fossil species found within each section.

Basic concepts of biostratigraphic principles were introduced many centuries ago, going as far back as the early 1800s. A Danish scientist and bishop by the name of Nicolas Steno was one of the first geologists to recognize that rock layers correlate to the Law of Superposition. With advancements in science and technology, by the 18th century it began to be accepted that fossils were remains left by species that had become deceased and were then preserved within the rock record. The method was well-established before Charles Darwin explained the mechanism behind it—evolution. Scientists William Smith, George Cuvier, and Alexandre Brongniart came to the conclusion that fossils then indicated a series of chronological events, establishing layers of rock strata as some type of unit, later termed biozone. From here on, scientists began relating the changes in strata and biozones to different geological eras, establishing boundaries and time periods within major faunal changes. By the late 18th century the Cambrian and Carboniferous periods were internationally recognized due to these findings. During the early 20th century, advancements in technology gave scientists the ability to study radioactive decay. Using this methodology, scientists were able to establish geological time, the boundaries of the different eras (Paleozoic, Mesozoic, Cenozoic), as well as Periods (Cambrian, Ordovician, Silurian) through the isotopes found within fossils via radioactive decay. Current 21st century uses of biostratigraphy involve interpretations of age for rock layers, which are primarily used by oil and gas industries for drilling workflows and resource allocations.

Fossils as a basis for stratigraphic subdivision
Fossil assemblages were traditionally used to designate the duration of periods. Since a large change in fauna was required to make early stratigraphers create a new period, most of the periods we recognize today are terminated by a major extinction event or faunal turnover.

Concept of stage
A stage is a major subdivision of strata, each systematically following the other each bearing a unique assemblage of fossils. Therefore, stages can be defined as a group of strata containing the same major fossil assemblages. French palaeontologist Alcide d'Orbigny is credited for the invention of this concept. He named stages after geographic localities with particularly good sections of rock strata that bear the characteristic fossils on which the stages are based.

Concept of zone
In 1856 German palaeontologist Albert Oppel introduced the concept of zone (also known as biozones or Oppel zone). A zone includes strata characterized by the overlapping range of fossils. They represent the time between the appearance of species chosen at the base of the zone and the appearance of other species chosen at the base of the next succeeding zone. Oppel's zones are named after a particular distinctive fossil species, called an index fossil. Index fossils are one of the species from the assemblage of species that characterize the zone.

Biostratigraphy uses zones for the most fundamental unit of measurement. The thickness and range of these zones can be a few meters, up to hundreds of meters. They can also range from local to worldwide, as the extent of which they can reach in the horizontal plane relies on tectonic plates and tectonic activity. Two of the tectonic processes that run the risk of changing these zones' ranges are metamorphic folding and subduction. Furthermore, biostratigraphic units are divided into six principal kinds of biozones: Taxon range biozone, Concurrent range biozone, Interval biozone, Lineage biozone, Assemblage biozone, and Abundance biozone.

The Taxon range biozone represents the known stratigraphic and geographic range of occurrence of a single taxon. Concurrent range biozone includes the concurrent, coincident, or overlapping part of the range of two specified taxa. Interval biozones include the strata between two specific biostratigraphic surfaces and can be based on lowest or highest occurrences. Lineage biozones are strata containing species representing a specific segment of an evolutionary lineage. Assemblage biozones are strata that contain a unique association of three or more taxa within it. Abundance biozones are strata in which the abundance of a particular taxon or group of taxa is significantly greater than in the adjacent part of the section.

Index fossils

Index fossils (also known as guide fossils, indicator fossils, or dating fossils) are the fossilized remains or traces of particular plants or animals that are characteristic of a particular span of geologic time or environment, and can be used to identify and date the containing rocks. To be practical, index fossils must have a limited vertical time range, wide geographic distribution, and rapid evolutionary trends. Rock formations separated by great distances but containing the same index fossil species are thereby known to have both formed during the limited time that the species lived.

Index fossils were originally used to define and identify geologic units, then became a basis for defining geologic periods, and then for faunal stages and zones.

Ammonites, graptolites, archeocyathids, inoceramids, and trilobites are groups of animals from which many species have been identified as index fossils that are widely used in biostratigraphy. Species of microfossils such as acritarchs, chitinozoans, conodonts, dinoflagellate cysts, ostracods, pollen, spores and foraminiferans are also frequently used. Different fossils work well for sediments of different ages; trilobites, for example, are particularly useful for sediments of Cambrian age. A long series of ammonite and inoceramid species are particularly useful for correlating environmental events around the world during the super-greenhouse of the Late Cretaceous.

To work well, the fossils used must be widespread geographically, so that they can be found in many different places. They must also be short-lived as a species, so that the period of time during which they could be incorporated in the sediment is relatively narrow. The longer lived the species, the poorer the stratigraphic precision, so fossils that evolve rapidly, such as ammonites, are favored over forms that evolve much more slowly, like nautiloids.

Often biostratigraphic correlations are based on a faunal assemblage, rather than an individual species — this allows greater precision as the time span in which all of the species in the assemblage existed together is narrower than the time spans of any of the members. Furthermore, if only one species is present in a sample, it can mean either that (1) the strata were formed in the known fossil range of that organism; or (2) that the fossil range of the organism was incompletely known, and the strata extend the known fossil range. For instance, the presence of the trace fossil Treptichnus pedum was used to define the base of the Cambrian period, but it has since been found in older strata. If the fossil is easy to preserve and easy to identify, more precise time estimating of the stratigraphic layers is possible.

Faunal succession
The concept of faunal succession was theorized at the beginning of the 19th century by William Smith. When William was studying rock strata he began to recognize that rock outcrops contained a unique collection of fossils. The idea that these distant rock outcrops contained similar fossils allowed for Smith to order rock formations throughout England. With Smith's work on these rock outcrops and mapping around England, he began to notice some beds of rock may contain mostly similar species, however there were also subtle differences within or between these fossil groups. This difference in assemblages that appeared identical at first, lead to the principle of faunal succession, where fossil organisms succeed one another in a definite and determinable order, and therefore any time period can be categorized by its fossil extent.

title: Biostratigraphy


text:
User:M.C. ArZeCh

Mostly just a bookworm who maintains an avid interest in pragmatism (James & Dewey, to some extent Rorty & Quine), magick, psychology, and a dozen other random little things that I don't know enough about. I hold a B.A. in psychology from the University of Washington and would like to do graduate work in the field, though my interests are also beginning to swerve in other directions these days.

title: User:M.C. ArZeCh