Sua (Single User Account) Versus Nat; Sip Alg; Table 48 Nat Mapping Types - ZyXEL Communications P-660HWP-D1 User Manual

Chapter 9 Network Address Translation (NAT)
The following table summarizes these types.

Table 48 NAT Mapping Types

TYPE
One-to-One
Many-to-One (SUA/PAT)
Many-to-Many Overload
Many-to-Many No Overload
Server

9.2 SUA (Single User Account) Versus NAT

SUA (Single User Account) is a ZyNOS implementation of a subset of NAT that supports two
types of mapping, Many-to-One and Server. The P-660HWP-D1 also supports Full
Feature NAT to map multiple global IP addresses to multiple private LAN IP addresses of
clients or servers using mapping types as outlined in
• Choose SUA Only if you have just one public WAN IP address for your P-660HWP-D1.
• Choose Full Feature if you have multiple public WAN IP addresses for your P-660HWP-
D1.

9.3 SIP ALG

Some applications, such as SIP, cannot operate through NAT (are NAT un-friendly) because
they embed IP addresses and port numbers in their packets' data payload.
Some NAT routers may include a SIP Application Layer Gateway (ALG). An Application
Layer Gateway (ALG) manages a specific protocol (such as SIP, H.323 or FTP) at the
application layer.
A SIP ALG allows SIP calls to pass through NAT by examining and translating IP addresses
embedded in the data stream.
When the P-660HWP-D1 registers with the SIP register server, the SIP ALG translates the P-
660HWP-D1's private IP address inside the SIP data stream to a public IP address. You do not
need to use STUN or an outbound proxy if your P-660HWP-D1 is behind a SIP ALG.
138
IP MAPPING
ILA1 IGA1
ILA1 IGA1
ILA2 IGA1
...
ILA1 IGA1
ILA2 IGA2
ILA3 IGA1
ILA4 IGA2
...
ILA1 IGA1
ILA2 IGA2
ILA3 IGA3
...
Server 1 IP IGA1
Server 2 IP IGA1
Server 3 IP IGA1
Table 48 on page 138.
P-660HWP-D1 User's Guide