Siemens 5890 User Manual

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SIEMENS 5890 DSL Router
User’s Guide
Chapter 6  Security Setup
NAT
SIEMENS
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NAT
Network Address Translation (NAT) provides a level of security by hiding the private IP addresses of your LAN 
behind the single public IP address of your router. All connections pass through the router and are translated 
by NAT. Network addresses on inbound traffic are translated from public to private IP addresses; while 
addresses on outbound traffic are translated from private IP addresses to the router’s public IP address. 
Besides translating addresses, NAT also authenticates a request or matches it to a previous request. 
Network administrators create a NAT table that does the global-to-local and local-to-global IP address 
mapping. To confiugre NAT:
1. Click NAT on the left navigation pane of the Router Information page. This displays the NAT Configuration 
page. 
2. In the NAT Passthrough section of this page, select Enable or Disable to specify whether or not multiple 
VPN clients are allowed. Enabled, multiple VPN clients are allowed; disabled, only a single VPN client is 
allowed. 
3. In the Outbound NAT Setting section of this page, select Enable or Disable to enable or disable NAT for 
communications from your LAN to the Wide Area Network (WAN). 
4. Click Apply.
5. Do both of the following:
Configure the WAN side for NAT support by clicking 
 from the left navigation pane. 
Configure the Local Machine for NAT support by clicking 
 from the left navigation 
pane.