Figure 180 Lan Computer Queries The Dns Server - ZyXEL Communications ZyWALL 1050 User Manual

Chapter 16 Virtual Servers
NAT Loopback Example
The NAT 1:1 Example on page 276
LAN SMTP mail server to allow users to access the SMTP mail server from the WAN. LAN
users can also use an IP address to access the mail server. However, you need to configure
NAT loopback for LAN users to use a domain name to access the server.

Figure 180 LAN Computer Queries the DNS Server

A LAN user computer at IP address 192.168.1.89 queries the domain name (xxx.LAN-
SMTP.com in this example) from a public DNS server and gets the SMTP server's 1-1 NAT
mapped public IP address of 1.1.1.1.
280
maps a public IP address to the private IP address of a
xxx.LAN-SMTP.com = ?
1.1.1.1
LAN
192.168.1.21
DNS
xxx.LAN-SMTP.com = 1.1.1.1
192.168.1.89
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