Ext. USB-HD question and oberservation (1 Viewer)

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Paradox-SJ

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Nov 20, 2003
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I am using a Buffalo 1TB DriveStation DUO in spanning mode. Its uses to 7200rpm SATA drive with 16mb cache. When I first installed it I could not play back HD material without sound and picture issues.

I was going to return it but decided to try a few things before hand just to make sue because I got it at such a really good price. ($299.00)I

First I reformatted it to FAT32 in spanning mode and ran read/write/io test against it. It was avg 10.2-10.5mb sec. (I didn’t know if this is fast or not)

Then I changed it to raid 0 and it was 9.8-10.1mb sec…So it is actually faster in spanning mode so that was not the issues.

I changed the drive write caching mode to Optimize for performance (this should be an windows only setting)

Switched it back to spanning mode and plug it back into my 622. The 622 reformatted it and I transferred a movie.

Low and behold it tranfered in record time (compared to before) AND when I went to play it back I no longer had any AV issues and I could even use trick play. (FF/RW to some extent)

In other words the problem was/is now solved. What brought about this change…I have no idea but if anyone else does I would love to hear it.

-------------------------
Now my question:

Why does it take so long to transfer material from the device to the 622 or vice-versa? I can transfer a 8gb file between other ext usb-HD and my computer in 10min or less this thing takes an hour or so to do the same thing.

What gives?
 
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Jim5506

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622/722 in encrypting/decrypting the data as it is transferred. Data on the 622 internal HDD is not encrypted, the EXT HDD is encrypted.
 

TheKrell

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Nay - en/decr doesn't have a weight here - if it will be true, you'll not available to play recordings from ESD.
Assuming you meant "wait", then this comment absolutely does not follow logically. Just because you can play an 8gB file from external storage in real time, it does not follow that a transfer with decryption isn't happening. It could very well slow that transfer down from 10 minutes (like a PC) to an hour, as reported by Paradox-SJ. P-SJ, what is the playing time of that 8gb file? I imagine it's longer than 1 hr.
 

Smith P.

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Oct 4, 2003
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I did measure transfer speed and posted it early - 3...5 Mbps; now HD movie have 8...12 Mbps bandwidth.
Do your math if transfer speed limited by encryption, but play speed with decryption 2 or 3 times is higher.
I think you telling things what still in clouds for you.
 
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TheKrell

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I did measure transfer speed and posted it early - 3...5 Mbps; now HD movie have 8...12 Mbps bandwidth.
Do your math if transfer speed limited by encryption, but play speed with decryption 2 or 3 times is higher.
:confused: Am I the only one around here confused by P.Smith's remarks? He seems to be saying that his transfer speeds are even more putrescent than the OP, who reported 8GB/hr (approx) speeds. That translates into... 17Mbps.

So, let's suppose P.Smith made a mistake and the OP was right with his 8GB/hr figure. (P.Smith seems to be claiming that the transfer rate is actually slower than real time! I can't believe any of you would blow $40 on such crappy performance!) Anyhow, given that HD movies only need 12Mbps, while the transfer goes at 17Mbps, then the receiver can clearly play movies off external archives without violating the laws of physics even if it's encrypting or decrypting on the fly. So, according to my math, Jim5506 is (most likely) right. And yes, P-SJ, the files are (in general) not encrypted on the 622 internal disk, except for a couple of channels whose names have escaped my memory at the moment.
 

Jim5506

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Data on internal HDD is readable, same data on ExtHDD is not readable with same method. There is a change of some type taking place between internal and external HDD.
 

Paradox-SJ

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Nov 20, 2003
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Data on internal HDD is readable, same data on ExtHDD is not readable with same method. There is a change of some type taking place between internal and external HDD.

So this supports that encyption is taking place during the transfer. No?

And thus the converse of decryption on play back?

All pointing to ONE of the reason for the slow transfer speeds and maybe even the poor trick play when playing for ext.HD
 
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