Welcome to Virtual-Notary, a free, secure, electronic notary service.

  1. How does it work?
  2. You select a factoid that you would like authorized. We check that factoid, create a record of it that you can refer to later, and issue you a cryptographically-signed certificate that attests to that factoid.

  3. What can I get notarized?
  4. Anything and everything that we can verify electronically. These include:
    Electronic documents, pictures, recordings, source code
    You can show that you possessed a specific document, picture or recording at a certain date. You can also acquire an unforgeable code hash certificate that you can distribute with your code.
    Web page contents
    You can prove that certain information was published on the web, even if it is deleted later. We'll make a copy of the said content for posterity.
    Social media content
    You can get notarized copies of Tweets, so you'll have documentation even if the owner deletes them later.
    Personal credentials
    You can get a record of institutional affiliation, e.g. you can demonstrate that you are gainfully employed.
    DNS and WHOIS records
    You can get a notarized record of the owner of a given DNS record at the time of forensic analysis.

  5. What are some usage scenarios where one would use a virtual notary?
  6. We list some sample use cases in this blog post.

  7. How trustworthy is virtual-notary?
  8. The Virtual Notary issues statements about online facts that it can ascertain independently. These factoids are then made available to you online (and you can share the URL with others if you like), as well as issued to you in the form of a cryptographically protected certificate (an X.509 attribute certificate). This certificate is protected with state of the art cryptography, and its validity can be checked at any time in the future, even if, for some reason, the virtual notary is shut down. Note that the Virtual Notary, like a real notary, does not check absolute facts (i.e. it cannot say "this is person X"); instead, it checks facts as it sees them from its own vantage point (i.e. it says "person presenting identification that says X"). The Virtual Notary does not claim that it is bullet-proof against being broken in; in fact, it is almost inevitable that every single website can be compromised by a sufficiently determined attacker. Consequently, the protocol is designed to contain and recover from such break-ins. One way transitions made through the public record, via the Bitcoin hash chain and Twitter updates, ensure that an attacker cannot tamper with the historical record.

  9. How does Virtual Notary protect its notary log?
  10. The critical data structure behind a notary service is a log documenting the history of transactions that have taken place up to that point in time. Virtual Notary protects this log using one-way hash functions to compute the serial number of each successive issued certificate. Since each certificate is dependent on the series of certificates that were issued prior, and since one-way hash functions render it practically impossible to craft a certificate that yields a particular desired hash, even an attacker who has compromised the system cannot insert a backdated certificate into the notary log. To further protect the notary log, Virtual Notary publishes the hash of the log every time a certificate is issued. Specifically, every time Virtual Notary issues a factoid certificate, Virtual Notary tweets the transition of the hash chain through the handle @VNotary. Further, Virtual Notary also records the transitions of the chain every 24 hours on the Bitcoin block chain by embedding the new hash in the output scripts of transactions made by the address .

    The Virtual Notary hashes are 64 bytes long but the Bitcoin output scripts allow us to embed only 40 bytes per transaction and hence two transactions are made every 24 hours to embed all 64 bytes of the hash. The output scripts in the transaction corresponding to the value of 0.0001BTC has the Virtual Notary hash embedded. The first 24 bytes of the Virtual Notary hash are prefixed with 16 '0's in the first transaction and the remaining 40 bytes of the hash appear as part of the second transaction.


  11. Is Virtual-Notary.org a legally-recognized notary?
  12. No. Virtual Notary is not recognized in any jurisdiction by the legal system as a notary public. The site is a technological proof of concept. It is no substitute for the use of a notary public in cases where the law mandates a legally-recognized notary public. That said, the certificates issued by Virtual Notary are cryptographically protected and strong. They can serve as trustworthy evidence in the same capacity as a statement from an independent third party.

  13. What happens if your service is terminated?
  14. First, we have no plans to ever terminate this service. Second, the service is constructed such that the certificates we issue are self-standing. Even if the Virtual Notary service were to be terminated, the certificates will be parse-able and meaningful to third parties. You do not need our involvement to prove that a certificate is valid.

  15. What happens if your service is compromised, or if you are corrupt?
  16. Our certificates provide strong assurance even against adversaries who may be able to break into our systems and even if the site is operated by corruptible people who may want to retroactively change the record of events kept by the notary.

    We do not claim our website to be perfectly secure against hacking. No website can credibly make that claim. Instead, we have implemented techniques on our servers such that even a corrupt notary cannot forge records and modify past history.