Digital Signature

Digital Signature in kerala | Digital Signature in aluva | Digital Signature in angamaly | Digital Signature in cochin | Digital Signature in Ernakulam

Digital signatures are often used to implement electronic signatures, a broader term that refers to any electronic data that carries the intent of a signature, but not all electronic signatures use digital signatures.In some countries, including the United States, India, Brazil, Indonesia, Saudi Arabia, Switzerland and the countries of the European Union, electronic signatures have legal significance.

Digital signatures employ asymmetric cryptography. In many instances they provide a layer of validation and security to messages sent through a nonsecure channel: Properly implemented, a digital signature gives the receiver reason to believe the message was sent by the claimed sender. Digital seals and signatures are equivalent to handwritten signatures and stamped seals. Digital signatures are equivalent to traditional handwritten signatures in many respects, but properly implemented digital signatures are more difficult to forge than the handwritten type. Digital signature schemes, in the sense used here, are cryptographically based, and must be implemented properly to be effective. Digital signatures can also provide non-repudiation, meaning that the signer cannot successfully claim they did not sign a message, while also claiming their private key remains secret; further, some non-repudiation schemes offer a time stamp for the digital signature, so that even if the private key is exposed, the signature is valid. Digitally signed messages may be anything representable as a bitstring: examples include electronic mail, contracts, or a message sent via some other cryptographic protocol.

Digital Signatures:

These are actually a subset of electronic signatures because they are also in electronic form. However digital signatures go much further in terms of providing security and trust services:

  1. Signer authentication:
  2. i.e. proof of who actually signed the document. i.e. digital signatures linking the user’s signature to an actual identifiable entity.
  3. Data integrity:
  4. i.e. proof that the document has not been changed since signing. The digital signature depends on every binary bit of the document and therefore can’t be re-attached to any other document.
  5. Non-repudiation:
  6. i.e. the signer should not be able to falsely deny having signed their signature. That is, it should be possible to prove in a court that the signer in fact created the signature.

This leads to some interesting points:

A digital signature can also be considered an e-signature, but the reverse is not true i.e., not all e-sign offer the same security services as digital signatures e.g. consider a basic e-signature like a scanned signature image inserted into a document – this can be easily copied from one document to another by anyone. Also the document can be easily edited after inserting the signature image.

Any mark on a document can capture the intent of the signer to “approve” the contents, i.e. this mark doesn’t necessarily need to look like the person’s hand-signature. Even a simple “X” is sufficient to show the signer’s intent. The issue is in terms of proving who could have made this mark.

To avoid later claims by the person that didn’t know what they were signing, it’s important to be able to show a legal notice to the user which they must confirm so that their signing action can be considered a wilful act.