Public Key Infrastructure ( PKI )

Abstract To use public key cryptography effectively on the Internet, one must know the owner of the private key that corresponds to a published public key. Public key infrastructure (PKI) provides this information. The workings of public key cryptography are not addressed here (for more on that topic, see the chapter on encryption). Rather, this chapter describes the basic concepts and components of PKI, comparing and contrasting alternative PKI architectures. Public key certificates, certificate revocation, and the protocols used in PKI management are described. Policies and procedures employed by a certification authority (CA) are also discussed. Attribute certificates, when used in conjunction with public key certificates, provide authorization information in addition to identification and authentication. Finally, future PKI developments are discussed.