You are concerned that if a private key is lost, all documents encrypted using your private key will be inaccessible. Which service should you use to solve this problem

Key escrow.

Explanation:

Cyber security can be defined as preventive practice of protecting computers, software programs, electronic devices, networks, servers and data from potential theft, attack, damage, or unauthorized access by using a body of technology, frameworks, processes and network engineers.

In Cyber security, encryption is a form of cryptography and typically involves the process of converting or encoding informations in plaintext into a code, known as a ciphertext.

Typically, an information or data that has been encrypted can only be accessed and deciphered by an authorized user.

Hence, if a private key is lost, all documents encrypted using that private key will be inaccessible to the users. Thus, the service that can be used to solve this problem is a key escrow because the cryptographic (private) keys kept in an escrow system are protected and would not be released to anyone other than the original user (owner).

A key escrow can be defined as a data security method of storing very essential cryptographic keys.

Simply stated, key escrow involves a user entrusting his or her cryptographic key to a third party for storage.

As a standard, each cryptographic key stored or kept in an escrow system are directly linked to the respective users and are encrypted in order to prevent breach, theft or unauthorized access.