ZyXEL Communications P-660HN User Manual page 103

The following lists out the steps taken, when a computer tries to access the Internet for the first
time through the ZyXEL Device.
1 When a computer (which is in a different subnet) first attempts to access the Internet, it
sends packets to its default gateway (which is not the ZyXEL Device) by looking at the
MAC address in its ARP table.
2 When the computer cannot locate the default gateway, an ARP request is broadcast on
the LAN.
3 The ZyXEL Device receives the ARP request and replies to the computer with its own
MAC address.
4 The computer updates the MAC address for the default gateway to the ARP table. Once
the ARP table is updated, the computer is able to access the Internet through the ZyXEL
Device.
5 When the ZyXEL Device receives packets from the computer, it creates an entry in the
IP routing table so it can properly forward packets intended for the computer.
After all the routing information is updated, the computer can access the ZyXEL Device and
the Internet as if it is in the same subnet as the ZyXEL Device.
P-660HN-Fx User's Guide
Chapter 6 LAN Setup
103