Advantages and Disadvantages of Digital Signatures
I have often had to answer the question "what is digital signature technology?" Most times, the question has been asked by regular people, smart but not highly technical and often the best way to explain it is to draw parallels between electronic documents and paper documents. For example, when you go to your bank and want to withdraw some cash, you will sign a withdrawal slip and sign on it then present it to the teller or cashier probably with your driver's license or some other form of personal identification. The cashier will compare your signature with what the bank has in its records and if they match they will process your funds withdrawal. On the other hand, if some thief were to get hold of your identification papers and attempt to withdraw funds from your bank account, they would most likely fail because they would be unable to provide a signature that matches yours.
What is a Digital Signature?
A digital signature is a mathematical scheme that is used to authenticate the sender of an electronic document. It ensures that the document is really from the sender and not from someone else while at the same time ensuring that the message that reaches the recipient is the same one sent without any alterations. Digital signatures are very efficient in legally binding documents because they are difficult to imitate and can be time-stamped.
How a Digital Signature Works
If you are sending a sensitive document, you would want the recipient of the document to know that it was from you and you would also want to ensure that the document gets to the recipient in the very same state you sent it in, without any alterations. The process of digitally signing your document would go something like this:
- First, you should copy the document and paste it into an e-mail note.
- Second, you use a special software to obtain a mathematical summary (commonly known as a message hash) of the contract.
- Thirdly, you will use a private key that you purchased from a trusted public-private key authority for encrypting the message hash.
- Lastly, you send your document with the message hash as your digital signature.
The digital signature can be used for signing any form of electronic document whether or not the message is encrypted. The digital signature is protected with a digital certificate that authenticates it. Your digital certificate will contain the certification-issuing authority's digital signature which makes it possible for anyone to verify that your certificate is real.
Advantages of Digital Signatures
The following are the main benefits of using digital signatures:
- Speed: Businesses no longer have to wait for paper documents to be sent by courier. Contracts are easily written, completed, and signed by all concerned parties in a little amount of time no matter how far the parties are geographically.
- Costs: Using postal or courier services for paper documents is much more expensive compared to using digital signatures on electronic documents.
- Security: The use of digital signatures and electronic documents reduces risks of documents being intercepted, read, destroyed, or altered while in transit.
- Authenticity: An electronic document signed with a digital signature can stand up in court just as well as any other signed paper document.
- Tracking: A digitally signed document can easily be tracked and located in a short amount of time.
- Non-Repudiation: Signing an electronic document digitally identifies you as the signatory and that cannot be later denied.
- Imposter prevention: No one else can forge your digital signature or submit an electronic document falsely claiming it was signed by you.
- Time-Stamp: By time-stamping your digital signatures, you will clearly know when the document was signed.
Disadvantages of Digital Signatures
Just like all other electronic products, digital signatures have some disadvantages that go with them. These include:
- Expiry: Digital signatures, like all technological products, are highly dependent on the technology it is based on. In this era of fast technological advancements, many of these tech products have a short shelf life.
- Certificates: In order to effectively use digital signatures, both senders and recipients may have to buy digital certificates at a cost from trusted certification authorities.
- Software: To work with digital certificates, senders and recipients have to buy verification software at a cost.
- Law: In some states and countries, laws regarding cyber and technology-based issues are weak or even non-existent. Trading in such jurisdictions becomes very risky for those who use digitally signed electronic documents.
- Compatibility: There are many different digital signature standards and most of them are incompatible with each other and this complicates the sharing of digitally signed documents.
Most businesses today are embracing the idea of paper-less offices. To do that, they have identified what is a digital signature and the advantages of using them. They are now using digital signatures to authenticate important documents and make legally binding agreements.