4 example 4: nat unfriendly application programs – ZyXEL Communications G.SHDSL.bis 4-port Security Gateway P-793H User Manual
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P-793H User’s Guide
Chapter 28 NAT Setup
295
Figure 175 Example 3: Menu 15.2
28.4.4 Example 4: NAT Unfriendly Application Programs
Some applications do not support NAT Mapping using TCP or UDP port address translation.
In this case it is better to use Many-One-to-One mapping as port numbers do not change for
Many-One-to-One (and One-to-One) NAT mapping types. The following figure illustrates
this.
Figure 176 NAT Example 4
Note: Other applications such as some gaming programs are NAT unfriendly
because they embed addressing information in the data stream. These
applications won’t work through NAT even when using One-to-One and Many-
One-to-One mapping types.
Follow the steps outlined in example 3 above to configure these two menus as follows.
Menu 15.2 - NAT Server Setup
Rule Start Port No. End Port No. IP Address
---------------------------------------------------
1. Default Default 0.0.0.0
2. 80 80 192.168.1.21
3. 25 25 192.168.1.20
4. 0 0 0.0.0.0
5. 0 0 0.0.0.0
6. 0 0 0.0.0.0
7. 0 0 0.0.0.0
8. 0 0 0.0.0.0
9. 0 0 0.0.0.0
10. 0 0 0.0.0.0
11. 0 0 0.0.0.0
12. 0 0 0.0.0.0