Chapter 12 Network Address Translation (NAT)

 

Table 52 Services and Port Numbers

 

 

 

SERVICES

 

PORT NUMBER

 

SNMP trap

 

162

 

 

 

 

 

PPTP (Point-to-Point Tunneling Protocol)

 

1723

 

 

 

 

Port Forwarding Example

Let's say you want to assign ports 21-25 to one FTP, Telnet and SMTP server (A in the example), port 80 to another (B in the example) and assign a default server IP address of 192.168.1.35 to a third (C in the example). You assign the LAN IP addresses and the ISP assigns the WAN IP address. The NAT network appears as a single host on the Internet.

Figure 75 Multiple Servers Behind NAT Example

A=192.168.1.33

192.168.1.1

B=192.168.1.34

IP address assigned by ISP

C=192.168.1.35 D=192.168.1.36

 

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VSG1432-B101 Series User’s Guide