So I’ve been researching online about this lately, but I can’t seem to find a comprehensive article that digs deep into this. I understand that the internet is decentralized and thus, packets are passed from router to router on the way to the destination, and I am aware of the underlying protocols and layers (link, application, etc), but when it comes down to the specifics of routing, there are just some things I can’t understand:
1. How is a packet’s route determined? Is it true that each router only has to decide which of its neighboring routers to pass the packet to? If so, how does that work?
2. How does a router know which direction the destination IP is physically located?
3. If a connection with a server is closed and then reopened, will the new connection follow the same route as before, assuming that each router along the way is still online?
4. Does each packet in a connection follow the same route as the others? If not, why?
5. How efficient is a typical route?
6. What role do ISPs play in all of this?
I know this is a lot of questions, but I would appreciate it if anyone here could help explain some of this. Thanks!
In: Technology
This isn’t really an ELI5 question… you’re asking for specific detail
Look up BGP routing, and routing tables. That should answer your specifics, and Mac addresses are used to identify physical devices
The ELI5 answer is that all the devices share various “rules” on where to send stuff, at varying degrees of granularity. The deeper into a network you go, the more specific they become, until it reaches its destination
Re: ISPs… they can agree to optimise routes by peering and getting direct connections to one another, but once something leaves their network they can’t directly influence it – however they can liaise with network teams in the ISP to try and improve things
HTH
Latest Answers