From the course: CISSP Cert Prep (2021): 4 Communication and Network Security

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ICMP

ICMP

- [Instructor] The Internet Control Message Protocol or ICMP is the housekeeping protocol of the internet. ICMP performs a variety of important administrative functions. Among these, the ping command is one of the most basic network troubleshooting commands available. When a system sends a ping command over the network, the receiving system responds with an acknowledgement. It's the equivalent of one system asking another, are you there? And the target system responding yes, I am. Although, instead of asking these questions in English, the ping command uses the ICMP protocol. The are you there question is asked by sending a packet known as an ICMP echo request and the target system responds yes I am by sending an ICMP echo reply. Let's try this from the command line using terminal on my MacBook, I'm going to try pinging my website certmike.com by typing in ping certmike.com. My computer begins sending ICMP echo requests…

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