Importance of 192.168.0.100
Dynamic Host Configuration Protocol or DHCP starts assigning of IP addresses with 192.168.0.100 while you are trying to access your LAN settings. Without this address, it would be difficult for the routers to differentiate among a host of IP addresses. A conflict scenario will arise because of the routers bearing same IP addresses.
Pinging for Connection Stability
You need 192.168.0.100 to communicate between different routers. This is because it is the IP address allocated for your server. Checking the connection status is possible whenever clients ping to this address. If there is no problem with this IP, then it means the server and clients can exchange information freely. All this is part of DNS settings setup.
Check you Local Settings
Firstly, you need to check your local connection settings. Run a check for any failures within your network itself. You may consider 192.168.0.100 as the ultimate option as it the default IP address given by the DHCP for the purpose of establishing contacts between different entities like clients and server.
In case there is no response, you might alter the router IP address from 192.168.0.100 to a different one. Now, type any domain name in the search bar and check whether you are able to access Internet.