ZyXEL Communications Broadband Security Gateway P-312 - Manual (Page 76)

P312 Broadband Security Gateway
NAT 6-3
2. Many to One: In Many-to-One mode, the Prestige 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 that previous ZyXEL routers supported (the SUA Only option in today’s routers).
3. Many to Many Overload: In Many-to-Many Overload mode, the Prestige maps the multiple local IP
addresses to shared global IP addresses.
4. Many to Many No Overload: In Many-to-Many No Overload mode, the Prestige maps the each local IP
addresses to unique global IP addresses.
5. 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 6-2 NAT Mapping Types
Type IP Mapping SMT abbreviation
One-to-One ILA1 !" IGA1 1:1
Many-to-One (SUA/PAT) ILA1
!" IGA1
ILA2 !" IGA1
…
M:1
Many-to-Many Overload ILA1 !" IGA1
ILA2 !" IGA2
ILA3 !" IGA1
ILA4 !" IGA2
…
M:M Ov
Many-to-Many No Overload ILA1
!" IGA1
ILA2 !" IGA2
ILA3 !" IGA3
…
M:M No Ov
Server Server 1 IP !" IGA1
Server 2 IP !" IGA1
Server 3 IP !" IGA1
Server
6.1.5 SUA (Single User Account) Versus NAT
SUA (Single User Account) in previous ZyNOS versions is a subset of NAT that supports two types of
mapping, Many-to-One and Server. See section 6.2.3 for a detailed description of the NAT set for SUA.
The Prestige now has Full Feature NAT support to map global IP addresses to local IP addresses of
clients or servers using all mapping types as outlined in Table 6-2. The Prestige supports NAT sets on a