If a client wants to send somthing to a server, the sequece is this:
- He needs to know its own IP address using DHCP
- He need to know server’s IP address using DNS
- He need to see if the server is in the same network with him via comparing the net id of their IP address;
If yes, it will not need the help of routers
If no, it will need the help of routers
- Either situation of 3, it firstly need to find the mac address of a router or the server, which need ARP
- If its need the help of router, the router will look up its routing table. If the router does not contain the IP address of the requested router, the router will find which next router could help.