P100IH ISDN Router
Step 5. Press [ENTER] at the “Press ENTER to confirm …” prompt to save your configuration after you define all the servers or press ESC at any time to cancel.
The most often used port numbers are shown in the following table. Please refer to RFC 1700 for further information about port numbers. Please also refer to our PNC Disk for more examples and details on NAT.
Table 4-6 Services & Port numbers
Services | Port Number |
FTP (File Transfer Protocol) | 21 |
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Telnet | 23 |
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SMTP (Simple Mail Transfer Protocol) | 25 |
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DNS(Domain Name System) | 53 |
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HTTP (Hyper Text Transfer protocol or WWW, Web) | 80 |
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PPTP | 1723 |
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4.6Examples
4.6.1Example 1 - Internet Access Only
In our Internet access example, we only need one rule where all our ILAs (Inside Local addresses) map to one dynamic IGA (Inside Global Address) assigned by our ISP.
Figure 4-15 NAT Example 1
NAT |
