ICMP hole punching
Have you ever played with a puzzle box? You have to put the right piece in the right hole to make it work, right? Well, internet communication is a bit like a puzzle box - the right messages have to go to the right places. One way to do this is by using ICMP, which is like a special type of message that helps computers "talk" to each other.
But sometimes, when two computers want to talk to each other, there's something blocking their path. Maybe it's like someone putting their hand over the puzzle box - the messages can't get to where they need to go. This is where ICMP hole punching comes in.
ICMP hole punching is like making a tiny hole in that hand so that the messages can get through. It works by using special messages called "echo requests" and "echo replies". When a computer wants to talk to another computer, it sends an echo request message. The other computer responds with an echo reply message.
But sometimes, these messages get blocked by something called a "firewall". It's like a security guard for the computer, making sure that only safe messages get through. To get past the firewall, the computers use a trick - they both send echo requests to a third computer at the same time. This confuses the firewall, because it doesn't know which echo request message goes with which computer. So it lets both messages through, and the two computers can finally "talk" to each other!
So that's icmp hole punching - it's like making a tiny hole in a puzzle box so that the right messages can get through. And just like with a puzzle box, it takes some clever thinking to figure out how to make it work.
But sometimes, when two computers want to talk to each other, there's something blocking their path. Maybe it's like someone putting their hand over the puzzle box - the messages can't get to where they need to go. This is where ICMP hole punching comes in.
ICMP hole punching is like making a tiny hole in that hand so that the messages can get through. It works by using special messages called "echo requests" and "echo replies". When a computer wants to talk to another computer, it sends an echo request message. The other computer responds with an echo reply message.
But sometimes, these messages get blocked by something called a "firewall". It's like a security guard for the computer, making sure that only safe messages get through. To get past the firewall, the computers use a trick - they both send echo requests to a third computer at the same time. This confuses the firewall, because it doesn't know which echo request message goes with which computer. So it lets both messages through, and the two computers can finally "talk" to each other!
So that's icmp hole punching - it's like making a tiny hole in a puzzle box so that the right messages can get through. And just like with a puzzle box, it takes some clever thinking to figure out how to make it work.