Polycom Audio and Video - Manual (Page 33)

Chapter 3 - Configuring Network Use
© Polycom, Inc. 3 - 13
There are two types of DMZs:
❑
Virtual DMZ — With a virtual DMZ, all ports through the router are opened
for the device in the DMZ (in this case, the V500). This has the affect of placing
the V500 on the outside of the router’s firewall. Keep in mind, however, that
the V500 may still be protected by some global firewall securities, which may
adversely affect video conferencing.
❑
Physical DMZ — With a physical DMZ, there is an actual, physical port on
your router, usually labeled DMZ, into which you plug your V500 LAN cable.
This port places the V500 physically outside of the firewall, which is usually
less restrictive, but is also less secure.
Typically, you should only use a DMZ when other configurations fail to allow
H.323 traffic to flow through unobstructed. If you do choose to place your V500 in
a DMZ, you must:
1. Make sure your router’s firewall software provides a DMZ.
2. Assign the internal IP address of the V500 to the DMZ.
For more information about how to perform these steps, refer to the
documentation that came with your router.
Configuring IP Network Support
After you have configured LAN properties and set up your IP network connection,
you may need to configure IP network support, depending on your network setup.
The only setting that you must set for making IP video calls is Enable IP H.323 on
the H.323 Settings screen. Settings for gateways, gatekeepers, SIP, and QOS are
optional depending on your network infrastructure. For example, if your network
does not have a gatekeeper or if you are not using SIP, you do not need to change
either of these settings.
Configuring H.323 Settings
H.323 settings enable you to allow IP dialing, as well as set up gatekeepers and
gateways:
❑
A gatekeeper supervises network traffic and manages functions such as
bandwidth control and admission control. The gatekeeper also handles
address translation, which allows you to make calls using static aliases instead
of IP addresses that can change each day.
❑
A gateway performs code and protocol conversion between IP networks and
ISDN, so that users on different networks can call one another. If the system is
configured to use a gateway, you must also configure it to use a gatekeeper.