So, I’ve had Zonealarm since not too long ago and I was getting messages like "has blocked access from X to your computer which seemed ok for the most part except on some ocassions it was clearly blocking stuff it should not block as it came from a copmputer I was communicating with but that’s ok… anyhow…
I’ve had ADSL for the last couple of days and now I am getting a new type of message: “the firewall has blocked routed traffic from site X (TCP port 515) to site Y …” I feel like I should call site Y and say “hey, I got a packet here addressed to you but I don’t know what to do with it!”
I am not much concerned but it got me thinking… The Internet works by servers relaying packets to one another so it makes sense they might want to pass something to me… except I can only send it back the way it came so it makes no sense.
And so, I realise I really haven’t a clue about how the Net works. My first assumption is servers must have multiple paths interconnecting them? Are all servers like that or only certain routers? I mean, do all servers do all sorts of stuff, including relay traffic and their own business? Or are there servers which just deal with moving traffic and then people like me who mind their own business? If so, how are they distinguishable? Or are packets just sent around wildly in the hope that some may arrive.
Can someone in the know give me a summary of a simplified explanation of how the Net works?