3 ms·

I'm not exactly sure what is being sold here. Is it an ostensibly-secure spreadsheet as a service? If I wanted a secure spreadsheet my instinct would be to us

by na85 10y ago

I'm not exactly sure what is being sold here. Is it an ostensibly-secure spreadsheet as a service? If I wanted a secure spreadsheet my instinct would be to use LibreOffice on an airgapped system and store it in an encrypted container of some kind... I'm not sure any sort of cloud solutions would even enter into my deliberations if I had truly sensitive stuff to work with.

davidcerezo 10y ago
It's not about encrypting files (encryption at rest): you can do the secure multi-party computations over your private LAN, and the encrypted network traffic will never leak to anybody (ie. no way to cryptanalyze anything in the future). It's about encrypting the computation between the parties: this kind of technology is being used to prevent satellite collisions on secret orbits, for example.
- na85 10y ago
  >It's not about encrypting files (encryption at rest): you can do the secure multi-party computations over your private LAN, and the encrypted network traffic will never leak to anybody Honest question: Can't I do that already by using SFTP or ssh and uploading a spreadsheet? I just feel like I'm missing something. Do you have some kind of real-time aspect going on? Second question: How do I know that your closed-source app isn't exfiltrating the data clandestinely? > (ie. no way to cryptanalyze anything in the future). Assuming no flaws are ever going to be discovered in your crypto scheme in the future is pretty bold. >It's about encrypting the computation between the parties: this kind of technology is being used to prevent satellite collisions on secret orbits, for example. Given that anything orbiting the earth can be observed from the ground with sufficient resolution, there's no such thing as a secret orbit. This sounds more and more like snake oil.
  - davidcerezo 10y ago
    >Honest question: Can't I do that already by using SFTP or ssh and uploading a spreadsheet? I just feel like I'm missing something. Do you have some kind of real-time aspect going on? No, you aren't encrypting the computation, just encrypting some data. Using secure computation (garbled circuits, secret sharing, homomorphic encryption, ...), you are encrypting every mathematical operation. > Second question: How do I know that your closed-source app isn't exfiltrating the data clandestinely? >Assuming no flaws are ever going to be discovered in your crypto scheme in the future is pretty bold. What I've written is: if you are carrying the secure computation on your private LAN and nobody is sniffing the traffic (potentially gigabytes), in the future they will have no way to cryptanalyze what the inputs were. And you can check that no information is being sent to anywhere during the secure computations: all the encrypted data is sent between the two computers carrying out the secure computation. > Given that anything orbiting the earth can be observed from the ground with sufficient resolution, there's no such thing as a secret orbit. This sounds more and more like snake oil. You can learn more here: https://eprint.iacr.org/2013/850 https://eprint.iacr.org/2013/850 https://eprint.iacr.org/2016/319 https://eprint.iacr.org/2016/319
    - na85 10y ago
      My skepticism was the secret orbits, not the shared multiprocessing. There's no such thing as a secret orbit.
      - anfractuosity 10y ago
        I think secret orbit just means the orbit might not be publicly published. I assume this is what is being referred to: https://sharemind.cyber.ee/private-satellite-collision-prediction/ https://sharemind.cyber.ee/private-satellite-collision-predi...
- debatem1 10y ago
  Who uses SMC for conjunction avoidance? I'm very curious to hear more about this.
smacktoward 10y ago
I agree it's confusing, but from my reading I think they're talking about a different kind of security than what you describe. It's more like this: you and I have some process we're collaborating on, and we both have an interest in getting accurate outputs from some kind of computation related to that process. But the only way to get really accurate outputs is to feed in proprietary, "secret" data from both your company and mine, and while we both have an interest in those outputs, neither of us wants to share our proprietary data with the other. This solves that problem by letting us each put our data into our own Excel workbook, mine visible only to me and yours only to you, and then get the output of some mutually-agreed-upon calculation using both of our inputted data, without ever seeing the numbers the other party put into their workbook. So if you and I can agree on formulas that would provide the outputs we want, and I trust you to enter accurate data on your end and you trust me on mine, we can now do a lot of interesting analysis without ever having to open our respective kimonos, as the saying goes (http://www.npr.org/sections/codeswitch/2014/11/02/360479744/why-corporate-executives-talk-about-opening-their-kimonos http://www.npr.org/sections/codeswitch/2014/11/02/360479744/...). I have no idea how well it actually works, or how secure the data flowing between the workbooks actually is. But it's an interesting idea!
- na85 10y ago
  >It's more like this: you and I have some process we're collaborating on, and we both have an interest in getting accurate outputs from some kind of computation related to that process. But the only way to get really accurate outputs is to feed in proprietary, "secret" data from both your company and mine, and while we both have an interest in those outputs, neither of us wants to share our proprietary data with the other. Ahh, that makes a little more sense. Seems like I could get your "secret" data by simply reversing the operation that gives us our shared result, though, doesn't it? Unless it's some kind of modulo type thing.
  - davidcerezo 10y ago
    No, you can't reverse anything. There are more details at: https://www.calctopia.com/2017/02/01/on-the-security-model/ https://www.calctopia.com/2017/02/01/on-the-security-model/

by na85 10y ago

davidcerezo 10y ago

It's not about encrypting files (encryption at rest): you can do the secure multi-party computations over your private LAN, and the encrypted network traffic will never leak to anybody (ie. no way to cryptanalyze anything in the future). It's about encrypting the computation between the parties: this kind of technology is being used to prevent satellite collisions on secret orbits, for example.

na85 10y ago
>It's not about encrypting files (encryption at rest): you can do the secure multi-party computations over your private LAN, and the encrypted network traffic will never leak to anybody Honest question: Can't I do that already by using SFTP or ssh and uploading a spreadsheet? I just feel like I'm missing something. Do you have some kind of real-time aspect going on? Second question: How do I know that your closed-source app isn't exfiltrating the data clandestinely? > (ie. no way to cryptanalyze anything in the future). Assuming no flaws are ever going to be discovered in your crypto scheme in the future is pretty bold. >It's about encrypting the computation between the parties: this kind of technology is being used to prevent satellite collisions on secret orbits, for example. Given that anything orbiting the earth can be observed from the ground with sufficient resolution, there's no such thing as a secret orbit. This sounds more and more like snake oil.
- davidcerezo 10y ago
  >Honest question: Can't I do that already by using SFTP or ssh and uploading a spreadsheet? I just feel like I'm missing something. Do you have some kind of real-time aspect going on? No, you aren't encrypting the computation, just encrypting some data. Using secure computation (garbled circuits, secret sharing, homomorphic encryption, ...), you are encrypting every mathematical operation. > Second question: How do I know that your closed-source app isn't exfiltrating the data clandestinely? >Assuming no flaws are ever going to be discovered in your crypto scheme in the future is pretty bold. What I've written is: if you are carrying the secure computation on your private LAN and nobody is sniffing the traffic (potentially gigabytes), in the future they will have no way to cryptanalyze what the inputs were. And you can check that no information is being sent to anywhere during the secure computations: all the encrypted data is sent between the two computers carrying out the secure computation. > Given that anything orbiting the earth can be observed from the ground with sufficient resolution, there's no such thing as a secret orbit. This sounds more and more like snake oil. You can learn more here: https://eprint.iacr.org/2013/850 https://eprint.iacr.org/2013/850 https://eprint.iacr.org/2016/319 https://eprint.iacr.org/2016/319
  - na85 10y ago
    My skepticism was the secret orbits, not the shared multiprocessing. There's no such thing as a secret orbit.
    - anfractuosity 10y ago
      I think secret orbit just means the orbit might not be publicly published. I assume this is what is being referred to: https://sharemind.cyber.ee/private-satellite-collision-prediction/ https://sharemind.cyber.ee/private-satellite-collision-predi...
debatem1 10y ago
Who uses SMC for conjunction avoidance? I'm very curious to hear more about this.

smacktoward 10y ago

I agree it's confusing, but from my reading I think they're talking about a different kind of security than what you describe. It's more like this: you and I have some process we're collaborating on, and we both have an interest in getting accurate outputs from some kind of computation related to that process. But the only way to get really accurate outputs is to feed in proprietary, "secret" data from both your company and mine, and while we both have an interest in those outputs, neither of us wants to share our proprietary data with the other. This solves that problem by letting us each put our data into our own Excel workbook, mine visible only to me and yours only to you, and then get the output of some mutually-agreed-upon calculation using both of our inputted data, without ever seeing the numbers the other party put into their workbook. So if you and I can agree on formulas that would provide the outputs we want, and I trust you to enter accurate data on your end and you trust me on mine, we can now do a lot of interesting analysis without ever having to open our respective kimonos, as the saying goes (http://www.npr.org/sections/codeswitch/2014/11/02/360479744/why-corporate-executives-talk-about-opening-their-kimonos http://www.npr.org/sections/codeswitch/2014/11/02/360479744/...). I have no idea how well it actually works, or how secure the data flowing between the workbooks actually is. But it's an interesting idea!

na85 10y ago
>It's more like this: you and I have some process we're collaborating on, and we both have an interest in getting accurate outputs from some kind of computation related to that process. But the only way to get really accurate outputs is to feed in proprietary, "secret" data from both your company and mine, and while we both have an interest in those outputs, neither of us wants to share our proprietary data with the other. Ahh, that makes a little more sense. Seems like I could get your "secret" data by simply reversing the operation that gives us our shared result, though, doesn't it? Unless it's some kind of modulo type thing.
- davidcerezo 10y ago
  No, you can't reverse anything. There are more details at: https://www.calctopia.com/2017/02/01/on-the-security-model/ https://www.calctopia.com/2017/02/01/on-the-security-model/