Nexland Pro: Interface Screens
Special Applications
Certain applications with 2-way communication need ports opened up in the firewall
in order to function. Normally you would open ports with the
Custom Virtual
Servers
interface screen. But Custom Virtual Servers only opens ports for the IP
address defined in its settings because firewalls can only open incoming ports for one
computer at a time on the LAN.
The
Special Applications
screen tries to get around this limitation by letting you set
what are called
“Port Triggers.”
The Pro will listen for outgoing traffic on a range of
ports from computers on the LAN and if it sees this, it will open an incoming port
range for that computer. Once the communication is done, the Pro will start listening
again so that another computer can trigger the ports to be opened for it. The caveat is
that it can happen for only one computer at a time… but triggers can be used very
quickly. There are just milliseconds from trigger to receive. It can give the illusion of
allowing multiple computers having the same ports opened.
Two things to remember:
1. Special Applications entries will not work very well with multiple computers
trying to activate streaming media or a heavy incoming/outgoing volume
(most games). Applications that require low throughput should work fine
with Port Triggers.
52
Nexland Pro: Interface Screens
2. The Pro will only listen for traffic on the LAN. This means that the computer
on the LAN will activate the trigger, NOT traffic from the outside. The LAN
application must initiate traffic and you must know the ports or range of ports
it uses in order to setup a Special Applications entry. If traffic initiates from
the outside, you must use setup a
Custom Virtual Server
.
Existing Special Apps
: If you have previously made an entry to this screen and you
want to
Update or Delete
it, you must first select it from the drop down menu and
then click “
Update Fields Below
” to access it's settings. If adding a new entry, don't
select from the menu or click “
Clear Form
” before adding new entry.
Special Application Data...
Name
: Give your Special App any short descriptive name.
Enable
: Check or uncheck to enable or disable your Special Application (disabling
will close the ports defined below). Remember to click “
Update
” if using with an
existing Special Application.
Outgoing Protocol
: Choose either TCP or UDP as the protocol type for sending data
(consult the application's support).
Outgoing Port Range
: Enter the Start and Finish ports used by your application when
it's sending data. If one port is used, enter the same number in both fields.
Incoming Protocol
: Choose either TCP or UDP as the protocol type for receiving
(consult the application's support).
Incoming Port Range
: Enter the Start and Finish ports used by your Application
when it's receiving data. If one port is used, enter the same number in both fields.
Click
Add
to Add a new entry
Click
Delete
to Delete the entry shown and free up Pro memory
Click
Update
if you have changed the entry shown
Click
Clear Form
before Adding a new entry
53
