Per-hop behaviour

Per-hop behaviour refers to how a network device (like a router or switch) handles packets as they pass through it on their way to their destination. Imagine that you are sending a letter to your friend who lives far away. You put the letter in a mailbox, and a mail carrier comes to pick it up. The mail carrier takes the letter to a mail sorting facility, where it gets sorted based on its destination. Then, it gets put on a truck and sent to another sorting facility, and so on, until it finally arrives at your friend's house.

In a network, packets work kind of like letters. When you send data over the internet, it gets broken up into packets, which are small chunks of data. Each packet has information about where it came from (the source) and where it's supposed to go (the destination). As the packets travel from your device to their destination, they pass through many different network devices, like routers and switches.

Each of these network devices has a per-hop behaviour that describes how it handles packets. For example, when a router receives a packet, it looks at the destination address to figure out where to send it next. Then, it might look at the packet's priority, or how urgent it is, and decide how quickly to send it. It might also check to see if there are any errors in the packet, and if there are, it might discard the packet or send an error message back to the source.

Each network device has its own set of rules for how it handles packets, and this is what we call its per-hop behaviour. This behaviour is important because it affects how quickly packets are delivered, how reliable the network is, and how well it performs for different types of data (like video streaming or file downloads). By understanding the per-hop behaviour of the network devices you are using, you can make better decisions about how to optimize your network for the best performance.