0

Is there any algorithm where user can prove to server that the encrypted data sent by the server has been re-encrypted/destroyed by user after reading it?

Lets assume there is a server and user. The server wants the proof that data sent to user has been re-encrypted/destroyed after it has been read. Assuming user didn't create multiple copies of data.

Though there is one option to encrypt with the servers public and sent the data back to server so that server can verify. But in this case I dont want the server to read actual data. So this scenario is ruled out.

This can be applied to the scenario where the customer stores the data in the third party servers and after the contract is finished he wants to make sure that the data has been destroyed by the 3rd party servers and proof is provided to the customer.

Assumptions : There are no multiple copies of data, Third party servers can access the data before deletion.

Thanks.

EDIT:

To the doubts raised by community member. Lets assume the server will give access to some other resource on providing information that data has been encrypted. Second one: I gave the example of public key encryption so that server can use his private key to decrypt , but I dont want server to read the data. I need something similar to that. I dont need 100% reliable solution. I just need a close one.

  • 1
    How can you possibly make the assumption that multiple copies of the data have not been made? What you're asking for is simply not possible and no amount of clarification or wishing on your part is going to change that. – Ben Oct 6 '16 at 12:24
5

Let's say you sent me a file. After a month, I decide to delete it. How on Earth do you expect to notice about an action done in my local machine?

And if magically you could do so, what's preventing me to send you a fake "confirmation" message that the data has been removed?

So to answer your question, no, there is no reliable proof that data has been encrypted/destroyed by the user.

  • Firstly thanks for responding. To answer your questions. Lets assume the server will give access to some other resource on providing information that data has been encrypted. To your second question: I gave the example of public key encryption so that server can use his private key to decrypt , but I dont want server to read the data. I need something similar to that. I dont need 100% reliable solution. I just need a close one. – share75 Oct 6 '16 at 8:54
  • @share75 your edit doesn't change anything. it's the same, still you're relying on a message the third-party will send you when the data is removed, and therefore, could be crafted to let you think the data was removed. – yzT Oct 6 '16 at 9:19

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.