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The original paper on Lisp by John McCarthy could be considered an important part of CS history: Recursive Functions of Symbolic Expressions and Their Computation by Machine (Part I)

Claude Shannon's A Mathematical Theory of Communication is good to know as well.

I don't know if any of the original papers by Turing, Church and von Neumann have been put online so post some links if you find them.

For interactive symbolic manipulation, Maxima is an excellent open-source alternative. For numerical applications, Numerical Python and its associated packages beat both Matlab and Mathematica in my opinion. For 3D visualization, you can get VTK, which also has Python bindings.

Maxima is also used occasionally as a rapid prototyping language, but it's proprietary and it has a lot of rough edges. You are probably better off using one of a number of open languages with similar features, like Scheme, OCAML, SML, Prolog, or Haskell.

Don't forget about C++, however. In many ways, C++ nowadays allows you to write numerical code more naturally than any of these other languages (yes, better than Matlab and Mathematica), it has by far the best libraries available for it, and it gives you excellent performance. And you can even do symbolic mathematics in C++, with the right libraries (though it's not interactive, of course).

We're few and far between but we're watching you!

A plan9 users orgy would no doubt be a truly frightening experience.

With names like DeGood, Bitting, Cox, Pike, Yigit, Boyd, Digby, petra, Skip - throw in a couple of the Japanese [you know what *they're* like] it would be a night to remember.

There's only one female poster on the mailing list that I can recall [luckily Scandinavian so at least she's probably broad minded].

So, dress up in your Glenda the Bunny suit and come and join the fun.

The Fourth Edition of Plan 9 includes a substantially reworked security architecture, described in the USENIX Security 2002 conference paper by Russ Cox, Eric Grosse, Rob Pike, Dave Presotto, and Sean Quinlan.

One particular aspect that other operating systems may wish to adopt is our single-signon solution. A process called factotum is used to hold credentials like passwords and public/private keypairs and perform cryptographic operations. Factotum allows clients to speak a variety of cryptographic protocols and therefore legacy application servers can participate in our single-signon system without change and without even knowing it exists.

The factotum has no direct permanent storage, but rather fetches credentials at startup from a secstore server on the network. To authenticate safely with the secstore, Password Authenticated Key-exchange is used; this implies that the user just has to remember and type one password and passive eavsdroppers or even active malicious intermediaries can not launch even a dictionary attack against the system. The credentials are encrypted for storage on secstore, so even an administrator there would have difficulty reading them.

To see the code for all this, download the Plan 9 distribution and look in /sys/src/cmd/auth, particularly subdirectories factotum and secstore. The libraries /sys/src/libmp and /sys/src/libsec may also interest you.

Queries to ehg@lucent.com.
Copyright © 2002 Lucent Technologies. All rights reserved.

C++ is first of all definitely a separate language, in the sense that a C++ compiler will fail to compile legal C code. (Many compilers accept both C and C++ code, but must necessarily process them as either C or C++, not both.) If C and C++ are not "separate languages", then converting code from C to C++ or C++ to C must be a trivial task.

C++ is also a separate language in the sense that good C++ code (the definition of which does seem to differ depending on which edition of Stroustrup you look at) looks little like good C code. The STL (and templates in general) and exceptions result in source code that looks little like C.

it is merely an incremental improvement, an add-on basically. That's why it's called C++ and not D.

Stroustrup wrote: "I picked C++ because it was short, had nice interpretations, and wasn't of the form ``adjective C.'' in his own FAQ. No mention of emphasis on C++ "merely" being an "incremental improvement".

If you're curious, yes, there was a B, but there was not actually an A (or rather, there was, but it was called ALGOL).

B came from BCPL.

Some people think that "legacy stretching back further than TeX" is not a "win".

These same people might question why you are suggesting that something "used for man page formatting on tty devices" should be used for printed documentation.

Of course, such people clearly don't know the power of groff (for those people: try printing man pages out, and you'll see that it handles paper copy very well), but you're not exactly selling it.

And really I would recommend (La)TeX because I think it's more usable (closer to "what you see is what you mean" than roff); but if someone doesn't want to use TeX, I would recommend looking to modern-day roff users for information on using it: Plan 9.

As an example look at the phone company. Before the Bell breakup they made plenty of money and produced probably nothing innovative, at least nothing that benefited the consumer.

Yeah, Bell Labs never invented anything that you use every day

Anyone else have a dog-eared 1st EDITION K&R C out there?

Liberal Arts? Really? Hmmm. I've got one of them valuable degrees. Had to go back and get a Master's in Computer Science it was so useful.

Perhaps I need to re-read an interview with Brian Kernighan

BTW, let's remember that Brian Kernighan is not a "high creator" of C. All he did was write the book with DMR. Here's an exact quote from the aforementioned interview:
"I can't comment on the 'worse', but remember, C is entirely the work of Dennis Ritchie"

Still, liberal arts? I guess so. I remember several times thinking "crap, this could be automated" ... That said will, as the TIMES article states, students doing "... projects like making their own Web pages and writing a few simple programs ..." give them anything more memorable than music appreciation gave business students twenty years ago?

Personally, I think K would do everyone a favor is he actually did send the artsy ones into the inner regions of the macines. Computers are likely to be an every day tool in their careers - but just that - a tool. The students will need to learn how to remain creative and original in spite of the conveniences of a computer automating the drudgery of composing notes, sentences, graphics, etc ...

Just the same way we need to keep teaching elemenatary school kids their times tables - in spite of the fact that they are now equipped with solar powered calculators.

On a lighter note, in a paper by by Dennis Ritchie detailing the history of Unix we get this juicy quote about K's wit ...it was not well into 1970 that Brian Kernighan suggested the name 'Unix,' in a somewhat treacherous pun on 'Multics'...

Of course, I can't let this go by without asking the all important question "What Would Bjarne Do?"

In addition to our WAN/LAN I also run a medium size phone switch (195 nodes / 16 IP Phones / 2 PRIs for switched access / 1 dedicated Long Distance T1). When you get to the corporate level you're buying a solution; not building one in house, because phones are essential to the day to day operation of the company. Period. I think generically when you say phone switch you're referring to everything telco past the demarc; switch T1s/PRIs, operate internal digital stations, provide analog lines, route calls, manage security, reporting/tracking/billing, Voicemail, Auto Attendants, Hunt Groups, Digital Faxing- the whole 7 layer enchilada. Few corporations are going to allow their IT departments to go the Slashdot way w/ so much on the line. A modern phone switch must reliably scale to thousands of nodes including IP devices, support Unified Messaging (receiving faxes & voice mails through PC), have reporting right out of the box, must be easy to use, and work on the first cut over. While the word 'easy' is certainly a very relative word- in my experience most geeks (a word of complimentary endearment in my vocabulary) can easily master telco while the reverse is not often true. Believe it or not, in the old days these were sometimes the roles of separate administrators / departments.

You're right that *nix is a perfect fit for all of this; remember Unix was invented at Bell Labs. The auxiliary applications are there; to support your phone switch you need to reliably record and report all activity across your switch for billing, acct. tracking, etc. I would guess that *nix runs the backbone.

If you'd like you can become a dealer for the company that claims to have 'the world's first Linux technology based voice processing' including Unified Messaging.

By the way I think that Bayonne is encompassed in the umbrella project of GNUComm; hopefully it's just a matter of time before someone finishes the Embedded Linux Phone Switch. As an incentive to anyone who develops and releases a free system: even used handsets cost big money for a particular phone switch; pick wisely 'cause you're most likely stuck with it for a little while. Caveat: you will most likely be pushed out of the market by softphones.

Since you're in the market and I just went through this myself contact me off list and I'll share my experience with Inter-Tel Technologies which is one of the fastest growing companies in the US (short version: no I don't work there and overall positive).

In addition to our WAN/LAN I also run a medium size phone switch (195 nodes / 16 IP Phones / 2 PRIs for switched access / 1 dedicated Long Distance T1). When you get to the corporate level you're buying a solution; not building one in house, because phones are essential to the day to day operation of the company. Period. I think generically when you say phone switch you're referring to everything telco past the demarc; switch T1s/PRIs, operate internal digital stations, provide analog lines, route calls, manage security, reporting/tracking/billing, Voicemail, Auto Attendants, Hunt Groups, Digital Faxing- the whole 7 layer enchilada. Few corporations are going to allow their IT departments to go the Slashdot way w/ so much on the line. A modern phone switch must reliably scale to thousands of nodes including IP devices, support Unified Messaging (receiving faxes & voice mails through PC), have reporting right out of the box, must be easy to use, and work on the first cut over. While the word 'easy' is certainly a very relative word- in my experience most geeks (a word of complimentary endearment in my vocabulary) can easily master telco while the reverse is not often true. Believe it or not, in the old days these were sometimes the roles of separate administrators / departments.

You're right that *nix is a perfect fit for all of this; remember Unix was invented at Bell Labs. The auxiliary applications are there; to support your phone switch you need to reliably record and report all activity across your switch for billing, acct. tracking, etc. I would guess that *nix runs the backbone.

If you'd like you can become a dealer for the company that claims to have 'the world's first Linux technology based voice processing' including Unified Messaging.

By the way I think that Bayonne is encompassed in the umbrella project of GNUComm; hopefully it's just a matter of time before someone finishes the Embedded Linux Phone Switch. As an incentive to anyone who develops and releases a free system: even used handsets cost big money for a particular phone switch; pick wisely 'cause you're most likely stuck with it for a little while. Caveat: you will most likely be pushed out of the market by softphones.

Since you're in the market and I just went through this myself contact me off list and I'll share my experience with Inter-Tel Technologies which is one of the fastest growing companies in the US (short version: no I don't work there and overall positive).

take a look at Plan 9... you'll find there what you're looking for...

This story from Dennis Ritchie tells of an error message in old versions of Unix that was actually sort of a Bell Labs version of "All your base".

From personal experience, one that sticks out in my mind is from Microsoft's Flight Simulator. If you auger into the ground, it says "Crash". If you bellyflop into Lake Michigan it says "Splash". But if you make a perfect landing, forgetting the minor detail of putting down your landing gear, it'd say "Crash! Lower your gear next time!" This message dates all the way back to MFS 1.0.

Dennis Ritchie has an explanation of it here.

BLAST has only been possible since a fundamental breakthrough by in 1996 by Foschini and friends. Foschini's work showed that the Shannon Law you learnt at Uni was not the full story. In fact, Shannon's Law can be written as a matrix equation and in the presence of multipath interference one effectively has a full capacity channel between each pair of antennae. 'N' Antennas at each end means 'N' times the capacity in the same bandwidth. Read Foschini's paper for a proper, quite readable, explanation:

G. J. Foschini, Layered Space-Time Architecture for Wireless Communication in a Fading Environment When Using Multiple Antennas , Bell Labs Technical Journal, Vol. 1, No. 2, Autumn 1996, pp 41-59.

Bell Lab's BLAST site also has more detail.

single secure sign-on for multiple domains

here
or
[pdf]

Claude Shannon was a great engineer and theorist. His seminal work, "The Mathematiccal Theory of Communication" created the field of information theory. Even though it was the first complete treatment of information theory, and is over fifty years old, it is still a good read for the mathematically inclined. You can obtain a reprint of this paper at the Bell labs website].

You need to be able to grok everything in "The Unix Programming Environment" by Kernighan & Pike.

Tats in addition to just about everything else listed here.

Claude Shannon was a great engineer and theorist. His seminal work, "The Mathematiccal Theory of Communication" created the field of information theory. Even though it was the first complete treatment of information theory, and is over fifty years old, it is still a good read for the mathematically inclined. You can obtain a reprint of this paper at the Bell labs website .

for instance CSP has a reasonable theoretical foundation and is infinitely nicer to program with than those locks and semaphors invented in the '70s...

here's a brief history and more accessible explanation. plan 9 has a nice C implementation.

so much nicer to program with!

for instance CSP has a reasonable theoretical foundation and is infinitely nicer to program with than those locks and semaphors invented in the '70s...

here's a brief history and more accessible explanation. plan 9 has a nice C implementation.

so much nicer to program with!

for instance CSP has a reasonable theoretical foundation and is infinitely nicer to program with than those locks and semaphors invented in the '70s...

here's a brief history and more accessible explanation. plan 9 has a nice C implementation.

so much nicer to program with!

See for example the work at Bell Labs reporting in 1998 which was also reported in the journal Nature (subscription required) as early as 1997. The mechanism by which this broad negative-TCE occurs is nonetheless spectacular -- the zirconia atoms basically get pulled in and fold over against each other as the oxygen atoms vibrate more intensely with heating. This recent announcement (and several more in the last few years) are Soundbite Science.

IANAA (I am not an archeologist) but the oldest reference to such an expression on groups.google (they need a Oldest first option...) that I could find was this post wich states:

Never underestimate the bandwidth of a station wagon full of mag tapes.
-- Dennis Ritchie

The quote is attribuited to Dennis Ritchie.

Flee in terror! It's coming!

factotum (plan 9's authentication agent) is not a single sign-on solution, although it can be when used in conjunction with secstore. what it does mean is that applications do not have to be burdened with complex and error-prone authentication code, and that there is one, well-verified, point in the system that holds secrets and understands the protocols.

in the factotum scheme, you can mark certain accounts (e.g. your bank account access) so that they will always require a password to be entered; you can also use the scheme without secstore (which is what i'm doing currently) which just forces you to type in each password the first time it's required. secstore is a means to store all your passwords in one place securely, which you can then use to prime factotum.

this is the essence of the plan 9 approach - choose an abstraction and write it in a simple, modular way so that it's applicable to a wide range of previously unanticipated scenarios. it's a wonderful system, and one that carries forward the true unix tradition, something that UNIX lost long ago.

factotum (plan 9's authentication agent) is not a single sign-on solution, although it can be when used in conjunction with secstore. what it does mean is that applications do not have to be burdened with complex and error-prone authentication code, and that there is one, well-verified, point in the system that holds secrets and understands the protocols.

in the factotum scheme, you can mark certain accounts (e.g. your bank account access) so that they will always require a password to be entered; you can also use the scheme without secstore (which is what i'm doing currently) which just forces you to type in each password the first time it's required. secstore is a means to store all your passwords in one place securely, which you can then use to prime factotum.

this is the essence of the plan 9 approach - choose an abstraction and write it in a simple, modular way so that it's applicable to a wide range of previously unanticipated scenarios. it's a wonderful system, and one that carries forward the true unix tradition, something that UNIX lost long ago.

BTW, Plan 9 is brought to you by the same Bell Labs research group that bought you Unix (according to a Plan 9 developer I talked to).

<snicker/>

And why, oh why must every "open source/free software columnist" being their articles with a potshot to Microsoft as a way to justify Linux's existence? Must they always do that? How about letting the technology stand by itself?

These slides (pdf) are a good intro to quantum computing, and explain how quantum operations could work.

Some of it is a bit above me, I think I will need to go back to my Uni text books before I can understand the proof on page 18. But it does go into some practical algorithms.

The page on error correction (page 27) is also sobering. Can anyone imagine a 100,000 bit computer that might only return one result every few seconds?

Assembly language is important, and needs to be taught, but I'm not sure first year is the place for it. Give the students a solid year of pascal or something strict, and get them into good habits while you can. Unless first years are of a lot higher standard then in Australia, teaching them assembly will ruin all the good things taught by pascal (or similar).

Spend it teaching them data structures, or algorithms. Something that will make them write chunks of code. Give them some API they have to use, doesn't have to do much, the one I liked was abstract data types in pascal. Get some one to write a heap binary tree, or a B-tree or something, and make them use the supplied API to store and get data.

Then and only then teach them assembly language. Teach them how a compiler works, and how a virtual machine works.

Then and only then can you teach them C. I still shudder at the memory of trying to teach the correct use of pointers. Once you know what a indiect reference, a stack and a heap is, paramter passing is easy.

The other usefull excesice for teaching dynamic memory is to write you own versions of malloc, realloc and free (thanks Rob Pike )

Already does a lot of this.

Well, it does.

Plan 9 from Bell Labs.

Have fun.

Yes, my software does essentially this, wrapped up in a nice utility (though, you get day resolution).

What we want, of course, is a better replica of plan9's dumpfs, featuring a real filesystem layer and compressed block differences. This is on my TODO list.

-jeremy

The South Pole research station has a bunch or radio telescopes. Like this

Of course, the prevalent wireless standard is 802.11, and 802.11 networking (also being based on radio frequencies) isn't allowed at the station because it messes up the telescopes.

I understand they have problems with people setting up rogue access points anyway. They track 'em down with this.

Quantum physics hasn't delivered anything for forty years.

Excuse me? Heterostructure lasers haven't been around for forty years yet, have they?

Check out this list of achievements that quantum physics has made for telecommunications.

Has there been, or ever will be, a form of Un*x that natively supports Unicode in all things?

From the 1995 paper describing "Plan 9" , the OS from the authors of Unix at Bell Labs:

Another departure from ANSI C is that Plan 9 uses a 16-bit character set called Unicode [ISO10646, Unicode]. Although we stopped short of full internationalization, Plan 9 treats the representation of all major languages uniformly throughout all its software.

I often like to sit out underneath the stars with a close girl-friend of mine, but one thing stands in the way of us seeing the natural beauty of the stars: Light Pollution.

When you mention this to people they often admit to not having noticed it before; after all, when was the last time you've been somewhere that strange sodium yellow streak wasn't shooting across the sky? If you weren't thinking about it you might take it to be a natural aura.

I saw a photo a while back (on the printed page, I've searched on Google and couldn't find it) of the night sky a 1000 miles west of Sydney Australia : the sky was still scared by the bright lights.

I found this picture on Google of light pollution from space: Light pollution over Canada circa 1975 As far as I am aware, this is of Canada, all though the picture isn't very clear I'm afraid it does illustrate a point about the long-reaching effects of light pollution.

On the greater impact outside of amateur sky watches, I can imagine this greatly hampers the efforts of earth-bound telescopes, and obviously explains why they are in such remote locations.

Is there anywhere on earth with NO light pollution?

Take a look at VeriSoft, "a tool for software developers and testers of concurrent/reactive/real-time systems."
http://www.bell-labs.com/project/verisoft/

so much of today's lax security is due to legacy design, not inherent difficulty. this is worth remembering.

My desktop isn't clucky or slow. It also doesn't look all that much like Windows. I'm not sure what the default Gnome config is nowadays, but my setup has a Mac-like menu bar at the top and no panel at the bottom. I rather like it.

As for bold, radical interfaces, sure that would be cool. In fact I noticed that some UI researcher did a presentation at the Gnome Summit. But the truth is that isn't going to attract mainstream users. They couldn't care less.

Object filing system, so for instance you can have people, and money as objects, and multiple directory hierarchies. I won't go into too much detail here.....

GUI based on Mozillas Gecko - with some optimisation that would be the most kickass graphics engine imaginable

Total network transparency: Linux is pretty good, but imagine having network swap, if you run out of hard disk space, objects that haven't been accessed for a while are swapped out to other computers. Net result: huge amounts of disk space.

Knowledge representation based APIs. Most operating systems use huge data structures passed to functions to control them. Windows is big offender, not sure about Linux (depends on desktop I think). However, the web is heading towards being based on AI knowledge representation systems - the semantic web. If the OS was internally built on logical assertions and RDF-style abstract data structures, it'd be in prime position for ultratight web integration.

www.slackware.com
www.redhat.com
www.debian.org
www.mandrake.org
cm.bell-labs.com/plan9dist/
www.atheos.cx
www.freebsd.org
www.openbsd.org
www.netbsd.org

That's that problem solved, then. Next, please!

It's okay, I get the two mixed up all the time, too.

O'Reilly Open Books Project
Bruce Eckel's "Thinking in..." books
Data Structures and Algorithms books
MIT's Structure and Interpretation of Programming Languages
Numerical Recipes series
Handbook of Applied Cryptography
The Art of Assembly Language Programming
Object-Oriented System Development
GTK+/Gnome Application Development
GNU Autoconf, Automake, and Libtool
Effective Perl (partial)
Programming Pearls (partial)

Hi,

If Martin Fowler's Refactoring is not on your list, it should be added.

This book is changing the way people write code, and is up there with Knuth's books, Kernighan and Ritchie, and Design Patterns in terms of influence over software development.

Start here, this is an introduction.

Then, beyond any doubt, you should read Shannon's original paper, published in 1948. There is some math involved (the course is normally taken on 4th year in a University), but don't worry.

Snannon's 1948 paper, and Kotelnikov's math (from 1933) laid the foundation of the information theory as we know it.

Alesis makes bad-ass 8-channel 20-bit digital audio recorders like the XT20 which store data on S-VHS tapes just fine . If you're just tuning in, the beauty of digital is that you can optimize your information storage/transmission for the medium/channel. (this is why Shannon is so cool) If you know the effective storage capacity of a piece of magnetic tape which is getting old has been stretched a bit, you encode the data at that capacity. That way the media can degrade a bit and you don't loose anything. If you use a nice robust encoding method, the media can degrade beyond that point and you still dont loose much. If you wanted to use regular VHS instead of a higher capacity tape, you just run the tape faster and don't pack the bits as tightly (probably not an issue as there's no mention in the article of using _actual_ VHS tapes, and 1. im sure they want to use more expensive media to prevent copying and 2. _actual_ VHS tapes should have been designed to hold about as much info as they do, and while going digital lets you optimize the space you have, HDTV may require more info than you can fit on conventional VHS tapes) Granted, you can destroy a tape, but you can destroy an optical disk too.

So, yeah, that was my short answer to "Seems to me you'd lose a lot of that HD picture after a few viewings too." ;-)

What Gupta and Kumar showed was that total capacity scales as sqrt(n) (repeating DOES increase TOTAL capacity! not just range). However per conversation capacity scales as n/sqrt(n) = 1/sqrt(n) -> 0 as n -> inf.

But Gupta and Kumar assume that when one station is transmitting, all others within its radius must be silent.

What Reed claims to be able to take advantage of is the technology of spatial and multi-path deconstruction using software radios that use multiple antennas to seperate multiple signals arriving at the same time on the same frequency. This technology is known as BLAST, and can be found at: ATT bell labs site

He seems to claim that the combination of multi-path software signal processing, cooperative repeaters, motion of many stations, and a cellular type access to wire or fiber backbones mean that for every new user the total capacity increases enough to support that user without degrading everyone else.

He doesn't seem to have a mathematical proof, but I am thoroughly convinced that we can at least massively scale individual's access to radio based data transmission with better technologies, and it is already the case that the regulations are terrible. So many of his points are right even if hhis theoretical result isn't perfect.

You can't beat "The Unix Programming Environment" by Kernighan and Pike. It was a great book when it was released in 1984 and it's great now. Same for Software Tools by Kernighan and Plaugher, from 1976.

You can't beat "The Unix Programming Environment" by Kernighan and Pike. It was a great book when it was released in 1984 and it's great now. Same for Software Tools by Kernighan and Plaugher, from 1976.