Certified Information Systems Security Professional (CISSP) Practice Exam

Link encryption operates by encrypting data at each point or node along the communication path. This means that as data travels through various routers, switches, and other network devices, it is encrypted and decrypted at each step. Essentially, every segment of the communication can be secured independently as it moves through the network.

This approach contrasts with end-to-end encryption, where the data is encrypted only at the source and decrypted only at the destination. Thus, the data remains in an encrypted state throughout its journey and is not accessible in a readable format at intermediate points.

Link encryption can provide benefits such as protecting data from unauthorized access at each node, but it also means that the data may be exposed during transmission at various points unless secured properly at each stage. This can make it less suitable for applications where data privacy is a paramount concern, as intermediate nodes need to be trusted.

The other options do not accurately capture the essence of the distinction. For example, while link encryption does encrypt entire communications in the sense of protecting data packets, its unique characteristic is the encryption performed at each node, which is where it significantly diverges from end-to-end encryption.