What is a critical function of an Intermediate CA?

An Intermediate Certificate Authority (CA) plays a key role in a Public Key Infrastructure (PKI) by creating and signing keys for leaf objects, which are the end entities, such as user devices or applications. This function is critical to establishing trust and ensuring the security of digital communications.

The Intermediate CA acts as a bridge between the root CA and the end entities. It inherits the trust of the root CA and delegates that trust to the leaf certificates it issues and signs, allowing for a hierarchical structure within the PKI. By creating and signing keys for leaf objects, the Intermediate CA ensures that these keys are verifiable and trusted, enabling secure communications and transactions.

This task is vital for maintaining the integrity and reliability of the entire PKI system, as the trust established by the Intermediate CA underpins the security of the data exchanged between users and systems. Other functions mentioned, such as creating and signing primary keys, distributing encrypted data, or performing audits, are not the primary responsibilities of an Intermediate CA in the context of its function within the PKI framework.