Data disposal: Every action leaves a trace
Footprints in the sand
We can then take the necessary steps to create an environment for informational safety:
- We can apply security at the intellectual property asset level (document or data field) to ensure that only those who are meant to see information do get to see it.
- We can apply controls on what can be done with the document, for example stopping a document from being printed, from cut and paste working, from being forwarded to others.
- We should apply the capability to rescind document access from those whom we decide we aren't as sure about as we might once have been, such that the document will self-destruct from their device should they try to access it.
- We need to make sure that when we delete a document, it is deleted. The disk drive on which it resides should hash over the file contents repeatedly until only the most indepth forensic tools would be able to recover the underlying information.
- Not only do we need to ensure that it deletes from us, but that it also deletes from any other systems where it resides, from our own backups and mirrors, from any recipients inboxes, from their file systems and so on, and that this is done through secure deletion.
Is this paranoia? I think that we have to take it as a given that within the majority of large organisations there will be information that it is unwise to have committed to any electronic form, but that email being one of the main means of communication will ensure that it is there.
Whether we want to have a means of legal deniability, or just corporate deniability, for some of the information is what we need to decide.
Linux has a built-in Shred command to get rid of information, but Windows and most flavours of Unix do not.
Even with Linux, we have a dependence on being able to see the physical disk, rather than the virtual pointers being held in a virtualised storage environment.
Therefore, we need to look at what else can be done, and a fully integrated storage management/information lifecycle management environment should be able to offer some form of solution.
Some of the vendors in this space are looking at the problem, but until there is end-user pull, it is unlikely we will see general availability of such capabilities, with only government security services and other high-requirement places having solutions in place, generally via bespoke coding.
Maybe it's time that we started making more noise, telling vendors that secure information and secure forensic deletion is a full requirement.
Only then will the vendor community put in the work to provide a fully integrated solution that is easy to use and yet really ensures that what we want to stay private, stays private and what we want deleted is deleted to all but the most stringent of forensic examinations.
There are point solutions available in the meantime, but making them available to everyone in an easy to use manner is not so easy.
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