ZyXEL Communications 10 - Manual (Page 147)

ZyWALL 10~100 Series Internet Security Gateway
NAT 12-5
2. Many to One: In Many-to-One mode, the ZyWALL maps multiple local IP addresses to one global IP
address. This is equivalent to SUA (i.e., PAT, port address translation), ZyXEL’s Single User Account
feature (the SUA Only option).
3. Many to Many Overload: In Many-to-Many Overload mode, the ZyWALL maps the multiple local IP
addresses to shared global IP addresses.
4. Many One to One: In Many-One-to-One mode, the ZyWALL maps each local IP address to a unique
global IP address.
5. Server: This type allows you to specify inside servers of different services behind the NAT to be
accessible to the outside world although, it is highly recommended that you use the DMZ port for these
servers instead.
Port numbers do not change for One-to-One and Many-One-to-One NAT mapping
types.
The following table summarizes these types.
Table 12-2 NAT Mapping Types
TYPE IP MAPPING SMT ABBREVIATION
One-to-One ILA1ÅÆ IGA1 1-1
Many-to-One (SUA/PAT) ILA1ÅÆ IGA1
ILA2ÅÆ IGA1
…
M-1
Many-to-Many Overload ILA1ÅÆ IGA1
ILA2ÅÆ IGA2
ILA3ÅÆ IGA1
ILA4ÅÆ IGA2
…
M-M Ov