ZyXEL Communications 2304R-P1 Network Router User Manual


 
Prestige 2304 Support Notes
All contents copyright (c) 2005 ZyXEL Communications Corporation.
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When do I need Multi-NAT?
a. Make local server accessible from outside Internet
When NAT is enabled the local computers are not accessible from outside. You can use Multi-NAT to make an
internal server accessible from outside.
a. Support Non-NAT Friendly Applications
Some servers providing Internet applications such as some mIRC servers do not allow users to login using the
same IP address. Thus, users on the same network can not login to the same server simultaneously. In this case
it is better to use Many-to-Many No Overload or One-to-One NAT mapping types, thus each user login to the
server using a unique global IP address.
What IP/Port mapping does Multi-NAT support?
NAT supports five types of IP/port mapping. They are: One to One, Many to One, Many to Many Overload,
Many to Many No Overload and Server. The details of the mapping between ILA and IGA are described as
below. Here we define the local IP addresses as the Internal Local Addresses (ILA) and the global IP addresses
as the Inside Global Address (IGA),
1. One to One
In One-to-One mode, the Prestige maps one ILA to one IGA.
2. Many to One
In Many-to-One mode, the Prestige maps multiple ILA to one IGA. This is equivalent to SUA (i.e., PAT, port
address translation), ZyXEL's Single User Account feature that previous ZyNOS 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 ILA to shared IGA.
4. Many to Many No Overload
In Many-to-Many No Overload mode, the Prestige maps each ILA to unique IGA.
5. Server