Digital Certificates - Legal Aspects of E-Commerce | E-Commerce - B Com PDF Download

Digital Certificate:

• It is an electronic document used to prove ownership of a public key. The certificate includes information about the key, information about its owner's identity, and the digital signature of an entity that has verified the certificate's contents are correct. If the signature is valid, and the person examining the certificate trusts the signer, then they know they can use that key to communicate with its owner.
• The most common use of a digital certificate is to verify that a user sending a message is who he or she claims to be, and to provide the receiver with the means to encode a reply. An individual wishing to send an encrypted message applies for a digital certificate from a Certificate Authority (CA). The CA issues an encrypted digital certificate containing the applicant's public key and a variety of other identification information. The CA makes its own public key readily available through print publicity or perhaps on the Internet. 
• The recipient of an encrypted message uses the CA's public key to decode the digital certificate attached to the message, verifies it as issued by the CA and then obtains the sender's public key and identification information held within the certificate. With this information, the recipient can send an encrypted reply.
• The most widely used standard for digital certificates is X.509. 

Contents Of a Typical Digital Certificate:

• Serial Number: Used to uniquely identify the certificate.
• Subject: The person, or entity identified.
• Signature Algorithm: The algorithm used to create the signature.
• Signature: The actual signature to verify that it came from the issuer.
• Issuer: The entity that verified the information and issued the certificate.
• Valid-From: The date the certificate is first valid from.
• Valid-To: The expiration date.
• Key-Usage: Purpose of the public key (e.g. encipherment, signature, certificate signing...).
• Public Key: The public key.
• Thumbprint Algorithm: The algorithm used to hash the public key certificate.
• Thumbprint (also known as fingerprint): The hash itself, used as an abbreviated form of the public key certificate.