Billion Electric Company BiGuard 10 User Manual

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application program (usually a server) incoming connections should be delivered to. 
Some ports have numbers that are pre-assigned to them by the Internet Assigned 
Numbers Authority (IANA), and these are referred to as "well-known ports". Servers 
follow the well-known port assignments so clients can locate them. 
 
If you wish to run a server on your network that can be accessed from the WAN (i.e. 
from other machines on the Internet that are outside your local network), or any 
application that can accept incoming connections (e.g. peer-to-peer applications) 
and are using NAT (Network Address Translation), then you will usually need to 
configure your router to forward these incoming connection attempts using specific 
ports to the PC on your network running the application. You will also need to use 
port forwarding if you want to host an online game server. The reason for this is that 
when using NAT, your publicly accessible IP address will be used by and point to your 
router, which then needs to deliver all traffic to the private IP addresses used by 
your PCs. Please see the WAN Configuration section of this manual for more 
information on NAT. 
 
BiGuard 2/10 can also be configured as a virtual server so that remote users 
accessing services such as Web or FTP services via the public (WAN) IP address can 
be automatically redirected to local servers in the LAN network. Depending on the 
requested service (TCP/UDP port number), the device redirects the external service 
request to the appropriate server within the LAN network. 
 
4.4.7.1  DMZ 
 
The DMZ Host is a local computer exposed to the Internet. When setting a particular 
internal IP address as the DMZ Host, all incoming packets will be checked by the 
Firewall and NAT algorithms then passed to the DMZ host, when a packet received 
does not use a port number used by any other Virtual Server entries. 
 
Caution: Such Local computer exposure to the Internet may face a variety of 
security risks.