Many years ago when I chose pat.net for my domain I had the option of grabbing pat.com. But I decided that I wasn't a business - I am a person. So.net seemed suitable for my own network connectivity.
I believe nuclear materials are safeguarded using a similar system. A bundle of fiberoptic cables is used as a "chain", with the ends somehow twisted and locked. The twisting has the effect of breaking some of the cables in a random pattern that can be verified or monitored continuously by shining a light through the bundle. Presumably any attempt to remove the cable (or cut it) would alter the pattern.
Java never had serious incompatability problems on the client side - Java's windowing toolkit AWT did. AWT was not written in Java. It was a huge (relative to Java) chunk of C code that stuffered from all of the incompatabilities and portability problems that C programs do in addition to the uncharted territory of trying to provide a cross platform GUI environment using native widgets.
The Java VM is, of course, a C program - but it is a tiny one. Almost all of the core Java libraries are written in Java itself, leveraging only very low level facilities. (Crypto is done in java, DNS is done in Java, etc.)
Swing, Java's pure Java GUI toolkit, is arguably the most modern, powerful , and portable GUI environment that exists right now. It is portable because it relies on only low level AWT facilities (simpe graphics areas and basic input) and then builds on top of that in pure Java.
At the time java was to first ship with Netscape, Sun had a pure Java version of the AWT toolkit. But Netscape apparently convinced them that native look and feel was more important than cross platform implementation. AWT - the buggy, non-portable, GUI C code - was thus hung around Java's neck.
If we'd had a pure Java GUI relying only on simple graphics primitives we could have build arbitrary interfaces that worked - cross platform - from the beginning. They would have been slow at first, and then rapidly gotten better (as Swing has).
Netscape set Java up and Microsoft knocked it down for a while at least...
-- Pat Niemeyer, Author of Learning Java, O'Reilly & Associates and the BeanShell Java scripting language.
This is a misconception - The only runtime phenomenon that Java requires is array bounds checking. Everything else - including all of its safety rules are performed in a static verification pass. This is what allows Java to be "jit'd" to native code and run at full speed.
However because Java has so much more structure by virtue of the intermediate byte code language a runtime profiler can dynamically optimize sections of code based on their behavior, not just their static characteristics.
Ask yourself - what can I do at compile time that I can't do better with more information at runtime? The answer is nothing... The only trade off is in start up performance and it's just a matter of time before the OSs handle that better.
Pat Niemeyer,
Author of Learning Java, O'Reilly & Associates
There should be two layers of protection between us and this phenomenon -someone tell me where I'm wrong.
First - every one of these exploits presumably overflows a C language buffer in some variation of read(). Why does C allow this? Why don't we build a better libc to fix this?
Second - Intel chips since the 286 have included domain memory management - Memory segments are supposed to be classified as DATA,STACK,TEXT, etc. How is it possible for an app to write to TEXT? Shouldn't the worst that the broken libc is able to do be to crash the app? Why don't OSs use this feature?
Please someone tell me how worms are possible today...
Pat Niemeyer,
pat@pat.net
What does p2p have to do with anything?
on
P2P Goes To War
·
· Score: 1
I have been amused by the p2p nonesense for a while now... But this story just makes no sense. In what way could p2p possibly help anyone build a simulator?
Anything that can be done with p2p can be done just as well without p2p, if you remove legal/ip boundries.
What we need then is a hash mechanism that is resistant to minor mechanical changes. Watermarking technologies (attempt to) do this for much harder things like sound and images. I'm sure it has been done for text.
Then to extend the concept we need to assign a probability to the spam. Perhaps your mail client would then sort it and show it to you colored yellow for probably spam so you could more easily delete it.
Pat Niemeyer
Author of Learning Java, O'Reilly & Associates
Slashdot Mirror
Maybe I'm just sleepy, but wasn't the anniversary two years ago?
Pat
Many years ago when I chose pat.net for my domain I had the option of grabbing pat.com. But I decided that I wasn't a business - I am a person. So .net seemed suitable for my own network connectivity.
Just a thought,
Pat
I also had no idea what that meant... I assumed they were obsoleting something.
Pat
I believe nuclear materials are safeguarded using a similar system. A bundle of fiberoptic cables is used as a "chain", with the ends somehow twisted and locked. The twisting has the effect of breaking some of the cables in a random pattern that can be verified or monitored continuously by shining a light through the bundle. Presumably any attempt to remove the cable (or cut it) would alter the pattern.
Neat.
Pat Niemeyer
Java never had serious incompatability problems on the client side - Java's windowing toolkit AWT did. AWT was not written in Java. It was a huge (relative to Java) chunk of C code that stuffered from all of the incompatabilities and portability problems that C programs do in addition to the uncharted territory of trying to provide a cross platform GUI environment using native widgets.
The Java VM is, of course, a C program - but it is a tiny one. Almost all of the core Java libraries are written in Java itself, leveraging only very low level facilities. (Crypto is done in java, DNS is done in Java, etc.)
Swing, Java's pure Java GUI toolkit, is arguably the most modern, powerful , and portable GUI environment that exists right now. It is portable because it relies on only low level AWT facilities (simpe graphics areas and basic input) and then builds on top of that in pure Java.
At the time java was to first ship with Netscape, Sun had a pure Java version of the AWT toolkit. But Netscape apparently convinced them that native look and feel was more important than cross platform implementation. AWT - the buggy, non-portable, GUI C code - was thus hung around Java's neck.
If we'd had a pure Java GUI relying only on simple graphics primitives we could have build arbitrary interfaces that worked - cross platform - from the beginning. They would have been slow at first, and then rapidly gotten better (as Swing has).
Netscape set Java up and Microsoft knocked it down for a while at least...
-- Pat Niemeyer,
Author of Learning Java, O'Reilly & Associates and the BeanShell Java scripting language.
This is a misconception - The only runtime phenomenon that Java requires is array bounds checking. Everything else - including all of its safety rules are performed in a static verification pass. This is what allows Java to be "jit'd" to native code and run at full speed.
However because Java has so much more structure by virtue of the intermediate byte code language a runtime profiler can dynamically optimize sections of code based on their behavior, not just their static characteristics.
Ask yourself - what can I do at compile time that I can't do better with more information at runtime? The answer is nothing... The only trade off is in start up performance and it's just a matter of time before the OSs handle that better.
Pat Niemeyer,
Author of Learning Java, O'Reilly & Associates
There should be two layers of protection between us and this phenomenon -someone tell me where I'm wrong.
First - every one of these exploits presumably overflows a C language buffer in some variation of read(). Why does C allow this? Why don't we build a better libc to fix this?
Second - Intel chips since the 286 have included domain memory management - Memory segments are supposed to be classified as DATA,STACK,TEXT, etc. How is it possible for an app to write to TEXT? Shouldn't the worst that the broken libc is able to do be to crash the app? Why don't OSs use this feature?
Please someone tell me how worms are possible today...
Pat Niemeyer,
pat@pat.net
I have been amused by the p2p nonesense for a while now... But this story just makes no sense. In what way could p2p possibly help anyone build a simulator?
Anything that can be done with p2p can be done just as well without p2p, if you remove legal/ip boundries.
Pat Niemeyer
What we need then is a hash mechanism that is resistant to minor mechanical changes. Watermarking technologies (attempt to) do this for much harder things like sound and images. I'm sure it has been done for text.
Then to extend the concept we need to assign a probability to the spam. Perhaps your mail client would then sort it and show it to you colored yellow for probably spam so you could more easily delete it.
Pat Niemeyer
Author of Learning Java, O'Reilly & Associates