User's Manual

Chapter 9 Network Address Translation (NAT)
AMG1202-T10A User’s Guide
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• One to One: In One-to-One mode, the ZyXEL Device maps one local IP address to one global IP
address.
• Many to One: In Many-to-One mode, the ZyXEL Device maps multiple local IP addresses to one
global IP address. This is equivalent to SUA (for instance, PAT, port address translation), ZyXEL’s
Single User Account feature that previous ZyXEL routers supported (the SUA Only option in
today’s routers).
• Many to Many Overload: In Many-to-Many Overload mode, the ZyXEL Device maps the
multiple local IP addresses to shared global IP addresses.
• Many-to-Many No Overload:
In Many-to-Many No Overload mode, the ZyXEL Device maps
each local IP address to a unique global IP address.
• Server: This type allows you to specify inside servers of different services behind the NAT to be
accessible to the outside world.
Port numbers do NOT change for One-to-One and Many-to-Many No Overload NAT mapping
types.
The following table summarizes these types.
Table 48 NAT Mapping Types
TYPE IP MAPPING
One-to-One ILA1ÅÆ IGA1
Many-to-One (SUA/PAT) ILA1ÅÆ IGA1
ILA2ÅÆ IGA1
…
Many-to-Many Overload ILA1ÅÆ IGA1
ILA2ÅÆ IGA2
ILA3ÅÆ IGA1
ILA4ÅÆ IGA2
…
Many-to-Many No Overload ILA1ÅÆ IGA1
ILA2ÅÆ IGA2
ILA3ÅÆ IGA3
…
Server Server 1 IPÅÆ IGA1
Server 2 IPÅÆ IGA1
Server 3 IPÅÆ IGA1