User`s manual

P-660 Series Support Notes

networks. It replaces the original IP source address (and TCP or UDP source port

numbers) and then forwards each packet to the Internet ISP, thus making them appear

as if they had come from the NAT system itself (e.g., the P-660 router). The P-660

keeps track of the original addresses and port numbers so incoming reply packets can

have their original values restored.

NAT Mapping Types

NAT supports five types of IP/port mapping. They are:

One to One

In One-to-One mode, the P-660 maps one ILA to one IGA.

Many to One

In Many-to-One mode, the P-660 maps multiple ILA to one IGA. This is equivalent to

SUA (i.e., PAT, port address translation), ZyXEL's Single User Account feature that

previous ZyNOS routers supported (the SUA only option in today's routers).

Many to Many Overload

In Many-to-Many Overload mode, the P-660 maps the multiple ILA to shared IGA.

Many to Many No Overload

In Many-to-Many No Overload mode, the P-660 maps each ILA to unique IGA.

Server

In Server mode, the P-660 maps multiple inside servers to one global IP address. This

allows us to specify multiple servers of different types behind the NAT for outside

access. Note, if you want to map each server to one unique IGA please use the One-

to-One mode.