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bleke

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Beamforming is cheap, for sectorial scan phone cpu can easily handle it, of course it will not be all big HQ image, but for initial scan is enough, but ADC with pulse generator - that one is expensive, for decent quality digital steering you need for example minimum 16 channel adc in mhz range and that one is not cheap. If you think it cheap go and google 128 channel ADC plus 128 pulse generators with protection circuit (i know somebody says overkill, but for ndt is pretty norm)

ndt - non destructive testing

[dead] 8 years ago

If you don't like Linus, you can always fork Linux and create DyslexicAtheist OS :), but no you are attacking, he clearly says few mails later, that killing machine without very good reason is big no:

I absolutely refuse to take any hardening patches at all that have BUG() or panic() or similar machine-killing in it.

It needs to be revised and is not cool(tm) project than creating new language and rethinking how to avoid any pointer arithmetic (starting from char *str, to arrays char str[999]) is not very easy task.

You can run whatever system (L4 with formal verification and written in super secure language...) as long as there no redundant checks you are already doomed from start. Stuxnet is nice example why critical system must have at least:

* Somebody periodically in person checking what happening and cross-checking results with operator

* Have alternative monitoring system, even amateur arduino system with rs-422/485 network and independent sensors, can become impenetrable wall for Stuxnet type worms.

There have been multiple times posted about this and i not following too much, but i haven't seen anybody who can tune even small cnc for small scale production in less than year where there virtually 0 defects (problems arise from software, used materials or even production changes; and they take long time). What i saw from PR tesla rushed and now got problems came to them. Of course it can happen and with human personal

It is more like "The smallest dogs always bark the loudest" a.k.a. make sure/at least try to remind why are you important for everybody who meet.

Sorry that sounded like i'm scorching you i didn't mean it. Yes agree with when using HW initializing code in constructors I ended with two types of 'constructors/inits': 1 - for object initialization 2 - just for hardware and calling manually :/.

note, static initializers works in embedded you need to execute functions between __init_array_start and __init_array_end before using any static object in gcc somewhere in program

From my perspective, most difficult part about containers is setting mount point and creating minimal root tree in which container tools like docker or lxc shines, of course when you need small specific container for your service it is nice to have working code on the hand.

Very ineffective solution for this type authentication, currently any manageable switch has option to enable packet switching only between selected ports (and is same with wirelesses, you can set that clients don't communicate directly), just use firewall plus few scripts and solution ready.

For universities there are thing as eduroam, which works like following: 1. there are 802.x authentication with certificates and users + password; 2. for legacy clients just landing page with firewall tricks

First thing what I do if it is my spacecraft i will not send anything until I'll far away enough to not be detected and probably won't point transmitter to planet which are investigated (I know that signal can be reflected back from cosmic debris, but who can send rock to other solar system won't have problem to calculate signal path which doesn't point to us)

Because IPv6 from user point of view it is 128 bit address and nothing more. From technical point there will be always that golden switch/router witch have problems with IPv6 and it is hardware bug, because router golden nobody will be new device for big chunk of money.

Every time i start to think about similar architecture I start thinink why nobody come with idea that to add Wi-Fi support dump pipe mode (direct L2 mode if i'm right) and all security/packet droping handled by higher layer; like direct OpenVPN packets on air and everything handled by software. Ofcourse it will hurt some performance but security you can have few sacrifices.

I guess today maybe no, but 10-15 years later and after one or few terrorists attacks with standard narrative, we will get in situation where without government id you could not write a comment, like today in china. This is not happening because of need security, but because of people ignorance and government greed to control everything.