hello

I know that a safe erasing of data must be done using at least 1 wipe pass. However my question is: do, also, several full formats the same effect? thanks  

- williamsonn

hello

I know that a safe erasing of data must be done using at least 1 wipe pass. However my question is: do, also, several full formats the same effect? thanks

Generally no. This is dependent on the particulars of the OS involved, the media (floppy or hd) and what switches have been applied with the format command (eg. DOS /u switch on a floppy).
Also, what do you mean by a " full" format?  

- williamsonn

I know that a safe erasing of data must be done using at least 1 wipe pass. However my question is: do, also, several full formats the same effect? thanks

Depends on the OS, and how a full format is implemented. For example, a full format under XP is not the same thing as a full format under Win7.  

In more detail, any "full format" in a NT based OS BEFORE Vista is not "destructive".
"Full format" in Vista and later does fill each and every sector of the volume with 00's (besides the sectors for the filesystem structures that will be re-written), so while not being a "complete" wipe (as anything outside the volume is left "as is") it is effectively destructive.
(the target of disk wiping is the disk, the target of "format" full or not is the volume).

For the record the notion

that a safe erasing of data must be done using at least 1 wipe pass

is inaccurate as there is not any documented report of anyone ever recovering anything after a single 00 pass, at least on "modern" hard disk, which means roughly those made in the last 10 years.


jaclaz
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I guess I am wondering why you are asking? It takes little time, and little expertise to seed a flash drive with dummy data, make a few notes of what is on there and where, and then format it with various OSes.

In the time it takes for you to post and wait for a reply, you'd have your answer first hand, rather than having an answer from unknown sources.  

In addition to what's been already said, full (or even quick) format of an SSD drive will normally destroy its content due to the TRIM/garbage collection operation. However, some remnants of original data may still appear in SSD's reserved memory areas, so saying that several cycles of full format destroy 100% of data on an SSD drive would not be technically correct.

Also, formatting a traditional (magnetic) hard disk, even if you're filling the sectors with zeroes, is not the same as using a cryptographically sound wipe. Properly implemented wiping fills disk content with random data (that must be cryptographically sound random data in order to pass certain certifications). This is due to the fact that, theoretically, data overwritten with zeroes can still be recovered off magnetic plates with dedicated hardware. Note that I said "theoretically", as I don't really know what happens if such hardware is used with a modern drive with high storage density and perpendicular writing.
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- Belkasoft

Properly implemented wiping fills disk content with random data (that must be cryptographically sound random data in order to pass certain certifications).

Belkasoft, would you recommend this for SSD?
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