What is Digital Signature

DIGITAL SIGNATURE

Digital signatures allow us to verify the author, date and time of signatures, authenticate the message contents. It is a process that guarantees that the contents of a message have not been altered in transit.

Digital signatures help to authenticate the sources of messages. For example, if a bank’s branch office sends a message to central office, requesting for change in balance of an account. If the central office could not authenticate that message is sent from an authorized source, acting of such request could be a grave mistake.


Once the message is signed, any change in the message would invalidate the signature. By property of non-repudiation any entity that has signed some information cannot be altered.

ADVANTAGES:

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: it is so cheap to use. Courier charges can be excluded.
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.
Time-Stamp: By time-stamping your digital signatures, you will clearly know when the document was signed.
Disadvantages

Expiry: it is based on technologies. So if no technology it will be expired.
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.