Very interesting topic. As I said earlier in another thread, I don't keep anything up in the cloud that I need to keep secure. Not so much for lack of confidence in the security of any given cloud provider, but just as a general practice. Then I don't worry too much if my cloud account is breached, other than my general dismay at a website getting breached. I also use a password manager(Dashlane https://www.dashlane.com/ for all of my password protected sites and I let Dashlane set the password. It does a good job of picking a strong password, and I don't have Dashlane upload my data to Dashlane's servers. I also have a pretty strong password on my local copy of Dashlane.

After a few data breaches like we have seen recently, I am a bit paranoid. Also, when I was in industry the company for which I worked had a couple of breaches in which my name, social security number and a few other choice bits of info were released. But those weren't breaches through the corporate network. One was a laptop theft, and the second was when the spouse of a colleague installed Limewire on a work laptop and in so doing exposed the laptop to the world. It isn't clear why that laptop had personnel data on it, but it did.

That being said, the university at which I now work has some pretty strong policies in place for faculty and staff with regard to data security. I have spent some time in the last couple of months improving the security of our local network(just the little bit that is our lab's), changing IP addresses on equipment so that they are not public, ensuring that none of our equipment is broadcasting such that anyone can connect.

I work in a med school, where HIPAA(health insurance portability and accountability act)controls our data usage. HIPAA is the mechanism by which access to patient information is controlled. Given that, we get periodic presentations by our IT guys on handling data. The med school also provides us with secure servers for data storage. I don't keep patient data on my local machine. I am not in a clinical setting anyway, so the only patient data that I have is from genetic screens that we are doing, and all of those data are anonymized so that even if the data were lost, no one could trace it back to a real person.

Finally, my iPad is encrypted, and I will be encrypting my laptop soon. While I don't have any sensitive data from work on my iPad, there are personal data on there I would like to keep safe. One of our IT guys told me that if we used the screen lock on the iPad, then the data are encrypted. I need to check this out. If it is not the case, then I need to get some encryption software. I do have some sensitive data on my laptop, but since it is anonymized, I don't have a lot of concern about that. I do have concern about my personal data.

Jim

MadaboutDana wrote:

But the decision of the US courts to insist that Microsoft
should hand over data held in Ireland has, I think, thrown a shadow over
100% US-owned services. What bothers me even more about that is the
failure by the Irish government to make any kind of statement along the
lines of 'hold on, that would be illegal under Irish law'. No, they're
too dependent on American goodwill to dare to do that.

I had missed this news; quite remarkable I dare say.

Interestingly, Amazon Web Services have just announced their Frankfurt-based infrastructure:
http://aws.amazon.com/blogs/aws/aws-region-germany/

Alexander Deliyannis wrote:

I had missed this news; quite remarkable I dare say.

Interestingly, Amazon Web Services have just announced their
Frankfurt-based infrastructure:
http://aws.amazon.com/blogs/aws/aws-region-germany/

Alex, that does not need to keep Amazon from giving NSA and other "authorities" access. Moreover: German agencies also spy on German and foreign citizens. :-(

Franz

Franz Grieser wrote:

Alex, that does not need to keep Amazon from giving NSA and other
"authorities" access. Moreover: German agencies also spy on German and
foreign citizens. :-(

I would have never thought that we are not taken good care of, heaven forbid...

I think it's foolhardy to trust any company in any country with data you really want to keep secure. The only way to ensure it's secure is if it is encrypted *locally* (on your local machine) with a strong passphrase that is never stored anywhere. You want a system where there is no way for the server administrator to ever decrypt your data -- the only way for the data to be decrypted is if you personally disclose the passphrase. Locally-encrypted systems are more likely to have this type of security.

I believe that boxcryptor classic provides such a system. If I recall correctly, the new version of boxcryptor does not.

The next-best is to have data that is encrypted on the server but using a key that is not stored anywhere. The problems with this type of a system are (a) you transmit your password to the server so it's always possible it's stored in some cache; and (b) there is more likely a backdoor because when your key is transmitted to the server it's possible they use it to create a dual-key encryption where they keep one backdoor key even though they don't have your primary key. This is not possible with locally encrypted systems where your password is never transmitted to the server. I think Apple's newly-announced iCloud security seems to be in this league, and they say they don't keep a backdoor or a copy of your password and cannot decrypt the data for law enforcement, so if you take them at their word that's a good model.

Note that any system where you can share your files with someone else has to have some kind of a second key. Mega.com (the successor to mega upload) has this type of system. They have some type of complicated scheme where they say they don't save the second key, and have run a contest to break their security which I believe resulted in no successful hacks, but because of the second key this system is inherently less secure. (And of course there's the question of whether you want to give your data to Kim Dotcom...) It's possible the new iCloud has this unstored second-key issue too - I don't know if you can share a file with someone else with it.

Either way, the point is that you don't want to rely on trusting some company -- anywhere in the world -- if they have any way to decrypt your data. It doesn't matter what country it is. The Hague Convention and other treaties allow for civil and criminal discovery in most countries, meaning that a subpoena from the U.S. will be enforced in those countries if it satisfies various requirements. Plus, just because a company is located in one country does not ensure that they will always host their data there, particularly if the company changes ownership. Local encryption with a long passphrase you never transmit anywhere is the best solution - that way you trust yourself, not some company.

dan7000 wrote:

The only way to ensure it's secure is if it
is encrypted *locally* (on your local machine) with a strong passphrase
that is never stored anywhere. You want a system where there is no way
for the server administrator to ever decrypt your data -- the only way
for the data to be decrypted is if you personally disclose the
passphrase. Locally-encrypted systems are more likely to have this type
of security.

Apparently this is the logic of Wuala:
https://www.wuala.com/en/learn/technology
"As a side effect, it is impossible to recover your password in case you forget it. You can test your cloud storage provider’s security by checking whether they offer password recovery or password reset. If yes, then it does not employ client-side encryption. With client-side encryption, security is embedded deeply in the design of the storage."

I haven't used Wuala much, but it is marketed as the Swiss approach to data security--with clear connotations of Swiss banks and money security...

Dan, after reading your very good summary of approaches, I was wondering how Wuala handles sharing of files. They explain the procedure, though I admit I didn't proceed to read the full paper:

"One of the main challenges with client-side encryption is key management. If you only want to back up, a single master key is enough. However, if you want to be able to share data selectively, your cloud storage must feature a sophisticated key management scheme. Wuala features such a system, called Cryptree, whose basic principles are described in this paper. http://dcg.ethz.ch/publications/srds06.pdf

Currently, Wuala uses AES- 256 for encryption, RSA 2048 for signatures and for key exchange when sharing folders, and SHA-256 for integrity checks."

I tried Wuala a couple of years ago and ended up dropping it because, if I recall, their Android client was slow and/or ugly. It's interesting that they have a dual-key encryption scheme to allow sharing --- that's what I think mega.com is doing too. Theoretically dual-key will be unbreakable (absent brute force) if nobody except the expected recipient gets the public key. See Wikipedia if you are interested - it's really cool stuff. But in practice most dual-key systems do you the favor of saving your public key for you so they can transparently decrypt your shared files for your recipients. Obviously if a provider can encrypt a file for your share recipient, they can also decrypt it under subpoena. Switzerland is a signatory to the Hague convention and thus will allow US litigants to compel the production of documents from Swiss companies (with the exception of banks pursuant to the Swiss Banking Privacy Act). See http://bern.usembassy.gov/obtaining_evidence.html

FYI (not very relevant to the initial question, but it might be of interest):


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