Re: How DHCP works?
I feel DHCP is rather on topic for network engineering.
Personally, I think it should be, but only to a certain degree. Configuring DHCP servers is certainly off-topic, although configuring DHCP in routers has been allowed, but a discussion of how the protocol works probably should be allowed. Based on previous, relatively-recent, DHCP questions which have been marked off-topic by the moderators, this question is off-topic, although I think it would be worth keeping an answering.
I found an old question with the answer to the question you have linked.