Some questions about section 2.
Regarding the WAN slide (4 of 6) in section 2:
1) Are nodes A2,B3,B1,C3 routers or PC's?
2) Where is says 'wan link 192.168.7.0/24' is this just referring to a cable between the nodes or some other hardware?
In the quiz, when it says 'The device that connects two different Layer 3 domains is commonly called a... router'. Is 'layer 3 domains' just another way of saying IP addresses?