Mastering Internet of Things

Using certificates

X.509 certificates are containers of cryptographic algorithm references and keys, as well as metadata, or claims that the certificate is supposed to make. These claims might be related to a name such as a domain name, email address, and so on. The claims are only valid for a given amount of time. A certificate contains an expiration date. After that date, the certificate automatically becomes invalid.

The algorithm references constitute an example of a loosely coupled architecture, making algorithms pluggable. As algorithms become obsolete, they can be exchanged for newer ones, without having to change the overlying architecture.

Certificates define a PKI. The public part of the certificate can be transmitted to others, ...