Find out what routers are crossed when accessing a server!

Question

I am new to this forum and not really sure if I this belongs here, but I give it a shot anyway.

What routers/switches/networks does a packet from my computer need to cross in order to access a lets say server www.google.com?

(I think this is pretty much impossible to know, since all I can see from my side is a question to my DNS server and then an answer)

Answer 1

For routers, use traceroute (the tools comes with Windows under the name tracert.exe). It rebuilds the path by sending packets with short lives (i.e. with a low "maximum number of hops") and inspecting the post-mortem ICMP packets which are sent back went a packet dies of old age (i.e. has reached its maximum number of allowed hops). Unfortunately, some networks block these ICMP, so the tool does not always work.

Switches do not exist at the IP level; they do not have an address or a name, so there is not much to report anyway.

Answer 2

A router is a device that takes traffic in an interface and directs it out an interface based on its next hop as listed in a routing table. When you do a traceroute from your server to google or any other site almost every hop is a router. Even a firewall is a router, just a specialized one that can filter and modify traffic.