Hello All Sorry if I'm posting this thread in a wrong place. I need your help ! I have two cisco routers , one cisco 800 series - this is the router of my ISP (I cannot login on it ), and one Linksys e 2500 series - this is my router. So, The ISP router give to my a LAN like 172.20.20.0/24 (I have some PC and servers connected on ti ) I configure my linksys with static IP, like IP 172.20.20.5 - and linksys LAN and wireless is like 192.168.1.0/24 . Everything it's seemed OK, i have internet from my linksys LAN, I can ping the servers on my LAN 172.20.20.0/24 from 192.168.0/24. But the problem is that i cannot ping or sharing files or connecting remotely form my ISP LAN 172.20.10.0/24 to my internal linksys LAN 192.168.1.0/24 Seemed like the ISP router doesn't know about my linksys LAN. Does thees router exchange routing tables with each other or not, or where is the problem ? Can you help me please ? Thank you !