What does active interception involve?

Active interception refers to the deliberate act of capturing or modifying the data that is being transmitted between a sender and a receiver. This is typically done with the intent to eavesdrop, steal information, or alter the information being exchanged without the knowledge of the parties involved. The key characteristic of active interception is the involvement of manipulation or alteration of the data in transit, distinguishing it from passive interception, where the data is simply observed without being altered.

In the context of network security, this could involve techniques such as man-in-the-middle attacks, where an attacker intercepts the communication and can either record or change the data being sent. This could lead to serious security breaches, making it essential for organizations to employ security measures to protect against such threats.

The other options do not accurately define active interception. Blocking unauthorized access pertains to defensive security measures, securing messages with strong encryption focuses on protecting data rather than intercepting it, and monitoring network performance is about observing network efficiency rather than actively interfering with data transmissions.