Insight DLTs - A first step to tamper-proof documents based on Distributed Ledger Technologies.
A practical use case to understand DLT technology using the IOTA tangle.
WHY READ THIS INSIGHT?
Nowadays, sharing documents and information has never been easier. It is possible to share information by e-mail, to make it available on websites for download or store it within various file systems distributed on hundreds of platforms worldwide.
Some examples of common file sharing systems:
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DropBox
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OneDrive
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GoogleDrive
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IPFS
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Bittorrent
The mentioned solutions work great as long as no one manipulates the documents.
However, how can anyone make sure the content created and shared through the different systems has not been manipulated or changed. Knowing that a minor change in the content could sometimes have great consequences. For example, someone changes somewhere a “one” for a “no”, which may lead to a complete different interpretation of the intended content.
Taking the above into consideration, let's show how to secure the content you wanted to share, using the new Distributed Leger Technologies (DLTs).
Let's talk about that.
SIGNETS AND HASHES - A SIGN OF TRUST.
Before we dive into the digital methods, let's take a look at a more simple example such as letters and see how it was made sure, they weren't manipulated while being sent.
A common method to do so is to use a signet or a seal pressed into sealing wax or stamped on an envelope over the closing. If the seal or stamp is received broken or not fitting correctly, then the letter has been most probably manipulated.
Similarly, we can check today if the information within a document has been changed or not by using Hashing Algorithm such as SHA256.
Simply explained, SHA is a repeatable cryptographic algorithm which takes the information and calculates a unique checksum of letters and numbers with always the same length.
To make sure this is true, we prepared a small example where you can try it yourself.
If you take the string “siticom.online” and use SHA256 to generate it’s checksum, you should receive the string
“8c21713c73598dd93afd81d2c7a1dbcf0dc99c16d70b4b6087cb2c9016e24987”.
If you tried it yourself, then you can be sure, that this is true. You can do the same with documents and files, which also can have a SHA256 checksum.
The term Secure Hash Algorithm (SHA) describes a group of standardised cryptological hash functions. These are used to calculate a test value for any digital document or information.
Beside SHA256, there are many other hashing methods which can be used to prevent manipulation. But for this Insight we will stay with SHA256. MD5 is another one which has a wide acceptance.
If you tried it yourself, then you can be sure, that this is true. You can do the same with documents and files, which also can have a SHA256 checksum.
Beside SHA256, there are many other hashing methods which can be used. But for this Insight we will stay with SHA256 to keep it small. MD5 is another one which has a wide acceptance.
If you want to verify, you can go to the webpage
https://emn178.github.io/online-tools/sha256.html
and try it yourself.
Just type “siticom.online” into the text box.
COMBINE SHA AND DLT TO MAKE PUBLIC DOCUMENTS SAFE.
So far, so good. If we have a document and generated the checksum, we know the document wasn’t changed at this moment. But how does this work if someone takes our document, changes it and sends it around with another checksum?
And here comes the DLT into play. Within a DLT we can store the checksum connected to a specific address which belongs to the author. This way it is possible to offer a check mechanism which allows to verify the information with a checksum tamper-proof stored in combination with a unique address.
For our small example we stored the checksum in the IOTA Tangle.
To make it easier for you we implemented a web site which allows easy to add information to the Tangle.
If you want to test it, go to the following DLT explorer - https://explorer.iota.org - and enter the following unique message ID
“7a10adce07fe5fc8fc8098c5ff13b2dcdb9962e7ffa7ceea05d96a7abb0f2f01”
within the search field. You should see the checksum, tamper-proof stored with the message ID.
A DID could be used as an unique digital ID which can be signed and confirmed by public organisations and governments.
The DID itself is tamperproof stored within a DLT and represents a person or organisation within the digital world.
As soon there are decentralized identifiers (DIDs) available, you can even connect a document directly and the author can additionally be certified by an official source, and you can even proof if the source where you get the message ID from is trustable.
WHITE PAPER.
Finally, some links and the white paper as PDF as free download.
LINKS.
If you want to know more about DIDs, SHA and tamper-proof documents, we added some links where you can find further details.