i need to create a network with 2 routers, 4 switches and 40 pc's, i connect a router with 2 switches, from those 10 pc's each, o do this 2 times, then i connect the 2 routers with copper cross over i configure the ip's on both networks but i can't ping between a pc on network 1 and one on network 2, someone told me about assigning an ip on both serial ports of the router but i do it and then nothing happens, how do i do it? i have no idea what to do now, i can't even ping pc's between switches under the same router.
i attach a screenshot of the network map