Few security tips on computer systems.

MrProfit · Oct 25, 2005

Quote from jaronimo:

UPS or surge suppressor. One or the other, never both.

Never plug a UPS into a surge suppressor, and never plug a surge suppressor into a UPS. This does not increase your protection, it actually lessens it.

I used to be able to explain why, but that part of my memory was deleted to make space for trading information. You can probably google it or find why on a UPS website if you are interested.

NO. There is a misunderstanding here:
I agree it is not allowed to plug a surge protector into the UPS. This is a correct statement. The reason is that any UPS output is not exactly the same as the power output in the wall socket. The wave is not exactly sinwave.
This can make a surge protector act as a filter and fail cutting your PC out.

Otherwise it is allowed.
Typical surge protector consists of one little coil, a simple capacity and the zener diode or a small element that burns short if the voltage exceeds certain voltage + fuse.

If the surge protector is more complicated (with an autotransformer or ferro-resonant transformer) then it is active and I'd not connect it with the UPS no matter the sequence.

Another correct statement is that most UPSes have such internal circuitry that there is no need to add any surgeprotection. However it doesn't hurt to plug the UPS in a simple surge protector, remembering the power rating of the protector has to exceed the power rating of the UPS.

bali_survivor · Oct 25, 2005

Quote from MrProfit:

.......
Also if you are a freak - do not use any laptop. These have keyloggers built in.
If you have any important data - you are vulnerable. I'll repeat:
All modern notebooks have hardware keyloggers built in. Beware!
.....

Where ever did you get that idea from that this is not a hoax?

Have you ever opened up your laptop or are you just going by some bullshit on the web?

You are just discrediting yourself with such nonsense.

Another naive armchair specialist who believes everything (s)he reads.

Maria

bali_survivor · Oct 25, 2005

Quote from MrProfit:

....

Otherwise it is allowed.
Typical surge protector consists of one little coil, a simple capacity and the zener diode or a small element that burns short if the voltage exceeds certain voltage + fuse.

....

Politely disagree.

A UPS is more often than not a switched power supply and if set behind a surge protector the surge protector can actually do more damage than good. Too much inductance just before the UPS....

Maria

bali_survivor · Oct 25, 2005

Quote from Goodfray:

For more safety, instal a reliable firwall in you PC.
The best one i know is ZoneAlarm
You can downlaod it for free

www.zonelabs.com

ZoneAlarm has a lot of incompatibility. Better to use a hardware based firewall with NAT and statefull inspection firewall (SIF).

Your machine will run snappier too (less load).

Threw out ZoneAlarm years ago in favour of sysgate personal firewall. (less problems) But that went too when I got an ADSL modem with a build in SIF.

Maria

jrlvnv · Oct 25, 2005

I am still trying to figure out what he meant by the ALT-CONTROL-DELETE statement. Went where he said and I found nothing about it

bali_survivor · Oct 26, 2005

Quote from jrlvnv:

I am still trying to figure out what he meant by the ALT-CONTROL-DELETE statement. Went where he said and I found nothing about it

Basically if you have a PC then you can set it in such a way that it asks for a password for logging on when you have booted up.

Under XP: go to Control Panel, User Accounts , Pick a Task => "change the way users log on and off" and untick "Use the Welcome screen". You will also need to set a password.

Hope this helps
Maria

maxpi · Oct 26, 2005

I found that TS8 would not run in a user account. It has to have a superuser account at the minimum to run. I am not sure how that is for security and in fact if anybody knows, please inform us all.

Max

dcraig · Oct 26, 2005

Quote from maxpi:

I found that TS8 would not run in a user account. It has to have a superuser account at the minimum to run. I am not sure how that is for security and in fact if anybody knows, please inform us all.

Max

The problem with running any software with superuser privileges is that if a vulnerability is exploited in that software the compromised code can do whatever it likes to the computer in question without restriction.

For example if you need superuser privilege to format a drive, and you are running as a normal user then an exploit cannot be used to format a drive. On the other hand if you were running as superuser, the compromised code can format the drive.

Microsoft and some software vendors have a lot to answer for in this area. Totally negligent.

MrProfit · Oct 26, 2005

Quote from bali_survivor:

Politely disagree.

A UPS is more often than not a switched power supply and if set behind a surge protector the surge protector can actually do more damage than good. Too much inductance just before the UPS....

Maria

Maria, it is nice you know more than average about electronics.
So please let me say one thing about the 'inductance":
The coil is a passive element!

It is like a resistor in a circuit.
It moves the phase a little bit.
It doesn't matter in a small frequency circuit like that.

It has a role to decrease the large spike when a surge occurs. That's it!

The coil might eventually get a little warm during load. UPS is gonna be fine. I promise.

bali_survivor · Oct 26, 2005

Quote from MrProfit:

Maria, it is nice you know more than average about electronics.
So please let me say one thing about the 'inductance":
The coil is a passive element!

It is like a resistor in a circuit.
It moves the phase a little bit.
It doesn't matter in a small frequency circuit like that.

It has a role to decrease the large spike when a surge occurs. That's it!

The coil might eventually get a little warm during load. UPS is gonna be fine. I promise.

Will have to , having studied electronics and robotics. Unfortunately your statement is incorrect since there will be a series / parallel circuit between the coil(s) and the capacitors used at the entry of the UPS's switching power supply.

Which has as a result that when the right high frequency impulse (read: spike) comes along the capacitor /coil circuit will nicely produce a very high voltage swing which is higher than the initial impulse.

Result: smoke escapes out of the parts and we both know that once the smoke has escaped we cannot put it back into the components and therefor the UPS will be RIP.

PS
in the future don't be belittling just because I am not male. I had to hold my ground when I studied and have a guts full of attitudes like that. Once again you are only doing damage to yourself.

Maria