Draytek Vigor2500V Manual page 54

Start Port: Specify the starting port number of the service offered by the local
host.
End Port: Specify the ending port number of the service offered by the local
host.
5.6 The Precedence of three variants of port mapping
The Vigor router supports three variants of port mapping methods: Port
Redirection, Open Ports and DMZ.
Port Redirection –The incoming packet is redirected to a specific local
computer or laptop if the port number matches that defined.
forward the port to another port locally.
Open Ports -- As Port Redirection (above) but allows you to define a
range of ports.
DMZ Host – This opens up a single computer or laptop completely.
All incoming packets will be forwarded onto the PC with the local IP
address you specified. The only exceptions are packets received in
response to outgoing requests form other local PCs or incoming
packets which match rules in the other two methods.
While you are using combinations of these three systems, there is a priority
structure. The precedence of these three types of port mapping is
defined as follows:
Port Redirection > Open Ports > DMZ
For example: The packet will be forwarded to the local address defined in
Port Redirection if the port number of an incoming packet matches a rule
specified in both Port Redirection and Open Ports.
NAT
5-9
You can