But that post was me needling Specmaster over his tribulations with that PL310; it was a backhanded suggestion as to how he could make all that misery just go away.
Of course, Spec did not take the bait.That's because he knows the fight is worth it and the noise floor is not
That energy might be better spent turning that one into a cheap battery charger and getting a proper lab supply.
mnem
The only way to combat this scenario, that I have seen used in practice, was figured out in the 1970s in Multics. You attach security labels to all your files, you attach security labels to all your terminals, someone who logs into one of those terminals gets their security labels (and of processes they run) downgraded to those of the terminal. Try and display a 'secret' document on a 'restricted' terminal - system stops you (and logs it). If you have 'secret' graded terminals you put them in a room with an ugly, uncompromising guard outside who relieves you of any cameras, notebooks etc. and strip searches you on the way out to check that you haven't found a way to write the recipe for Kentucky Fried Chicken down the inside of your thigh.
Security is, first and foremost, a people problem and always will be; attempts to solve it with just computer technology will fail. Encryption is only ever good for ensuring that stuff is secure when it's being transported through, or stored in, somewhere that isn't secure. Proper 'secret' level security is always expensive.
Expalin 'covert channels' to them, and that TLS is riddled with them, therefore the MITM box could quietly give away everything, and watch them turn green.
So one of my Fluke 8800A's needs a minor repair. The 200mV/200 ohm range LED is intermittent. Sometimes comes on, sometimes doesn't, and even sometimes randomly flashes. So today I figured I'd pull it apart and see what's up.
Wouldn't you know it. The manual that I have is complete EXCEPT for the schematic of the display panel. So off to Artek Manuals and pay the $8 USD for a download. At least I know it will be a good copy and complete. But they "lock down" their PDF's and you can't copy/paste pages or portions of pages and drop into a separate file. Oh well.
Perhaps this can help you:
https://www.wikihow.com/Unlock-a-Secure-PDF-File
You can also get very usable results using the snipping tool to screencap directly from your .pdf viewer.
mnem
So one of my Fluke 8800A's needs a minor repair. The 200mV/200 ohm range LED is intermittent. Sometimes comes on, sometimes doesn't, and even sometimes randomly flashes. So today I figured I'd pull it apart and see what's up.
Wouldn't you know it. The manual that I have is complete EXCEPT for the schematic of the display panel. So off to Artek Manuals and pay the $8 USD for a download. At least I know it will be a good copy and complete. But they "lock down" their PDF's and you can't copy/paste pages or portions of pages and drop into a separate file. Oh well.
Perhaps this can help you:
https://www.wikihow.com/Unlock-a-Secure-PDF-File
You can also get very usable results using the snipping tool to screencap directly from your .pdf viewer.
mnem
Where does one find this alleged snipping tool?
So one of my Fluke 8800A's needs a minor repair. The 200mV/200 ohm range LED is intermittent. Sometimes comes on, sometimes doesn't, and even sometimes randomly flashes. So today I figured I'd pull it apart and see what's up.
Wouldn't you know it. The manual that I have is complete EXCEPT for the schematic of the display panel. So off to Artek Manuals and pay the $8 USD for a download. At least I know it will be a good copy and complete. But they "lock down" their PDF's and you can't copy/paste pages or portions of pages and drop into a separate file. Oh well.
Perhaps this can help you:
https://www.wikihow.com/Unlock-a-Secure-PDF-File
You can also get very usable results using the snipping tool to screencap directly from your .pdf viewer.
mnem
Where does one find this alleged snipping tool?
https://support.microsoft.com/en-us/windows/use-snipping-tool-to-capture-screenshots-00246869-1843-655f-f220-97299b865f6b
Also PowerToys, because fukkin' awesome: https://github.com/microsoft/PowerToys
mnem
*occasionally useful*
https://support.microsoft.com/en-us/windows/use-snipping-tool-to-capture-screenshots-00246869-1843-655f-f220-97299b865f6b
Also PowerToys, because fukkin' awesome: https://github.com/microsoft/PowerToys
https://www.howtogeek.com/665780/all-microsofts-powertoys-for-windows-10-explained/
And the old Image resizer PowerToy for those still flogging Win-not-10: https://www.bricelam.net/ImageResizer/
mnem
*occasionally useful*
Or "Shift" + "Windows Key" + "S" Only on win10 though.
Another problem management and admins make is to restrict everyday data that does not need to be restricted. The restrictions become a pain and workers find work-arounds for stuff that does not matter, but then the work-arounds get used on stuff that does matter. Another is enforcing "complex" passwords that humans can't remember so they write them down
Same with physical security. Years ago I was with the boss viewing a building the company was thinking of buying. The server room had RFID access control but the tags we were given were not on the list. Took me less tthan a minute to get in. They had mounted the reader on a plate so I unscrewed that and operated the door release mistakes made were mounting on a plate bypassed the reader anti-tamper (no I'm not saying what it was) and they had made the wiring connectons obvious
Aircraft software - Boeing 737 bug where if you were on a ILS approach on a specfic heading in a number of specific ranges of lat and long ALL FIVE primary flight and navigation displays go blank Fortunatly there were only about a dozen runways on the right heading in the affected locations.
Well I guess it time to decide what to do with the Thurlby PL310 after all the flipping time I've spent on it and the trouble its been, so I'll just have to put it on one side and wait for the time being........ until I need to use it. Yes that does indeed mean that its fixed and working again and ready for active duty, the little beauty...
Well I guess it time to decide what to do with the Thurlby PL310 after all the flipping time I've spent on it and the trouble its been, so I'll just have to put it on one side and wait for the time being........ until I need to use it. Yes that does indeed mean that its fixed and working again and ready for active duty, the little beauty...
Okay... so what eventually was the culprit...? Or are you working up a big post and gonna leave us hanging 'til the big reveal...?
mnem
he would never do that.
Another problem management and admins make is to restrict everyday data that does not need to be restricted. The restrictions become a pain and workers find work-arounds for stuff that does not matter, but then the work-arounds get used on stuff that does matter. Another is enforcing "complex" passwords that humans can't remember so they write them down
Same with physical security. Years ago I was with the boss viewing a building the company was thinking of buying. The server room had RFID access control but the tags we were given were not on the list. Took me less tthan a minute to get in. They had mounted the reader on a plate so I unscrewed that and operated the door release mistakes made were mounting on a plate bypassed the reader anti-tamper (no I'm not saying what it was) and they had made the wiring connectons obvious
Aircraft software - Boeing 737 bug where if you were on a ILS approach on a specfic heading in a number of specific ranges of lat and long ALL FIVE primary flight and navigation displays go blank Fortunatly there were only about a dozen runways on the right heading in the affected locations.
That door thing reminds me of the "security consultants" that we had come in once to check machine room security at a defence facility. One of them walked about a metre back and shouldered the door and it opened right up . Had to replace 100 odd doors due to that
The only way to combat this scenario, that I have seen used in practice, was figured out in the 1970s in Multics. You attach security labels to all your files, you attach security labels to all your terminals, someone who logs into one of those terminals gets their security labels (and of processes they run) downgraded to those of the terminal. Try and display a 'secret' document on a 'restricted' terminal - system stops you (and logs it). If you have 'secret' graded terminals you put them in a room with an ugly, uncompromising guard outside who relieves you of any cameras, notebooks etc. and strip searches you on the way out to check that you haven't found a way to write the recipe for Kentucky Fried Chicken down the inside of your thigh.
Security is, first and foremost, a people problem and always will be; attempts to solve it with just computer technology will fail. Encryption is only ever good for ensuring that stuff is secure when it's being transported through, or stored in, somewhere that isn't secure. Proper 'secret' level security is always expensive.
Yep spot on. I built a DMS years ago based on that principle but with some extensions for time-windowing access, working groups and better auditing
My favourite find in recent years was when I pointed a Software Composition Analysis product at itself (BlackDuck) and it found some holes. They hadn't even run their own product on their own code and it was shipping a vulnerable Tomcat implementation
We’ve all done it
You hit the jackpot with that. It’s one of the nice series in an old case
Well I guess it time to decide what to do with the Thurlby PL310 after all the flipping time I've spent on it and the trouble its been, so I'll just have to put it on one side and wait for the time being........ until I need to use it. Yes that does indeed mean that its fixed and working again and ready for active duty, the little beauty...
Okay... so what eventually was the culprit...? Or are you working up a big post and gonna leave us hanging 'til the big reveal...?
mnem
he would never do that.haha, yeah, the culprit was ME.
Well I guess it time to decide what to do with the Thurlby PL310 after all the flipping time I've spent on it and the trouble its been, so I'll just have to put it on one side and wait for the time being........ until I need to use it. Yes that does indeed mean that its fixed and working again and ready for active duty, the little beauty...
Okay... so what eventually was the culprit...? Or are you working up a big post and gonna leave us hanging 'til the big reveal...?
mnem
he would never do that.haha, yeah, the culprit was ME.
LOL... sure proof that you are a engineer, even if only in spirit.
mnem
Part 2 of the PL310 saga.
PL310 part 2
Then I decided to revisit everything as I must have missed something along the way and working backwards until I reached the pass transistor, the 2N3055, and found that all the problems had been of my own making, oh the shame of it I had missed wired it and had the base and emitter leads reversed
Reversed these and powered up, bingo it is only fecking working, my only defence is that I must have had a senior moment when soldering the leads up.
When its been warmed, the reading do agree with each other to with 1 mV.
We’ve all done it
You hit the jackpot with that. It’s one of the nice series in an old caseGood job I never put the collector on the base, that sucker has 51V on it, lucky the wire was just too short to reach eh? Yeah I'm really pleased about it being newer than it looks.
The only way to combat this scenario, that I have seen used in practice, was figured out in the 1970s in Multics. You attach security labels to all your files, you attach security labels to all your terminals, someone who logs into one of those terminals gets their security labels (and of processes they run) downgraded to those of the terminal. Try and display a 'secret' document on a 'restricted' terminal - system stops you (and logs it). If you have 'secret' graded terminals you put them in a room with an ugly, uncompromising guard outside who relieves you of any cameras, notebooks etc. and strip searches you on the way out to check that you haven't found a way to write the recipe for Kentucky Fried Chicken down the inside of your thigh.
Security is, first and foremost, a people problem and always will be; attempts to solve it with just computer technology will fail. Encryption is only ever good for ensuring that stuff is secure when it's being transported through, or stored in, somewhere that isn't secure. Proper 'secret' level security is always expensive.
Yep spot on. I built a DMS years ago based on that principle but with some extensions for time-windowing access, working groups and better auditing
Multics also had all those, and more. Multics is still worthy of study for hints of how to do things from a security perspective now (53 years after its first delivery). It was designed as a computing utility (utility in the sense of the electric company et al) in the days when people only foresaw large centralised computer systems. As such it was designed to be used by mutually distrustful groups, and to achieve military grades of security - it was the first system to get Orange Book B2 accreditation. It had many worthy and well thought out features (like a system security administrator role account that couldn't do anything except run the security tools). Starting point for finding more: https://multicians.org/security.html.
Whoops! The whole recent tendency to throw whole big third party subsystems (e.g. Tomcat) into products is just asking for trouble.