User`s guide
 Vigor300B Series User’s Guide 
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The UPnP facility on the router enables UPnP aware applications such as MSN Messenger to 
discover what are behind a NAT router. The application will also learn the external IP 
address and configure port mappings on the router. Subsequently, such a facility forwards 
packets from the external ports of the router to the internal ports used by the application. 
The reminder as regards concern about Firewall and UPnP 
Can't work with Firewall Software 
Enabling firewall applications on your PC may cause the UPnP function not working 
properly. This is because these applications will block the accessing ability of some 
network ports. 
Security Considerations 
Activating the UPnP function on your network may incur some security threats. You 
should consider carefully these risks before activating the UPnP function.  
¾  Some Microsoft operating systems have found out the UPnP weaknesses and hence 
you need to ensure that you have applied the latest service packs and patches.   
¾  Non-privileged users can control some router functions, including removing and 
adding port mappings.  










