What is the relationship between Public Keys and Certificates?
In Public Key Cryptography, if Alice wants to send a secret message to Bob, she must obtain a copy of his public key. Before doing so, however, she needs to make sure that the public key really belongs to Bob. Certificates (also called Digital IDs) address this problem. A certificate is an electronic document that binds a public key to a particular individual or organization. Certificates are issued by a trusted third party, called a Certification Authority (CA). Before issuing a certificate, a good CA will go though a series of authentication procedures to make sure that Bob is who he claims to be, and that the public key in the certificate really belongs to Bob. Your certificate will contain the following information: • your organization’s common name (e.g. www.verisign.soltrus.com) • additional identifying information (e.g. IP and physical address) • your public key • expiration date of the public key • name of the CA that issued the ID (i.e.
