ZyXEL Communications P-660 User Manual

P-660 Series Support Notes

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.

The following table summarizes these types.

NAT Type

IP Mapping

Mapping
Direction

One-to-One ILA1<--->IGA1

Both

Many-to-One
(SUA/PAT)

ILA1---->IGA1
ILA2---->IGA1
...

Outgoing

Many-to-Many
Overload

ILA1---->IGA1
ILA2---->IGA2
ILA3---->IGA1
ILA4---->IGA2
...

Outgoing

Many-to-Many No
Overload

(Allocate by
Connections)

ILA1---->IGA1
ILA2---->IGA3
ILA3---->IGA2
ILA4---->IGA4
...

Outgoing

Server

Server 1
IP<----IGA1
Server 2
IP<----IGA1

Incoming

SUA Versus NAT

SUA (Single User Account) in previous ZyNOS versions is a NAT set with 2 rules,
Many-to-One and Server. The P-660 now has Full Feature NAT support to map
global IP addresses to local IP addresses of clients or servers. With multiple global IP
addresses, multiple severs of the same type (e.g., FTP servers) are allowed on the
LAN for outside access. In previous ZyNOS versions (that supported SUA 'visible'