I'm having a hard time understanding some "basic" things...
I know a bit about configuring routing using CISCO packet tracer exercises (static routers, rip, ripv2, ospf, eigrp), but I have a doubt that I really need help figuring it out.
During the CISCO routing lessons I had, I always configured LAN's with routers on the edge of the LAN, connected using Serial ports between them and using only L3 (routing only) between every router (static routes or some routing protocol configured to reach other networks). I always thought that was what my ISP router did to reach other networks, routing my traffic only. But from what I see, my ISP delivers the Internet traffic to the WAN port on my ISP router using a VLAN, so they tag the Internet packets. Shouldn't be pure routing? I never used a VLAN when configuring routing protocols, I only used it inside LANs (so behind the edge router), to route vlans inside a LAN (routing on a stick), but never to route them outside.
The other question is:
I have a FTTH connection and my Public IP is (I will change it because of security purposes): 82.125.100.200 and from what I can see on the router configuration the subnet mask is /24, and the gateway is 82.125.100.1.
The thing is: why when I do a tracert on my machine, to for example, google.com (or any other website), the 2 hop (the 1º is my router 192.168.1.254) is a private ip: 10.252.128.1? The 2 hop shouldn't be the gateway of the router: 82.125.100.1?
I'm sorry my questions doesn't make much sense? But right now I'm very confused :(
Thanks to every one!!