Final answer:
A communication trigger in penetration testing happens when a network/system is found to have been previously compromised, prompting immediate communication with the client.
Step-by-step explanation:
In the context of penetration testing and network security, a communication trigger occurs when a penetration tester discovers that a network or system has previously been compromised by another attacker. In this situation, it is important for the penetration tester to immediately communicate this discovery with the client instead of waiting until the test is complete.
The communication trigger happens when a penetration tester discovers a security vulnerability so serious that it must be addressed immediately instead of waiting until the test has been completed.
This communication serves to alert the client about the existing compromise, enabling them to take appropriate actions to mitigate further damage and secure their network/system. It helps the client understand the current state of their security and make informed decisions regarding remediation and protection strategies.