Appendix D. Nat/Firewall Traversal - Vidyo VidyoGateway Administrator's Manual

Appendix D. NAT/Firewall Traversal

There are two possibilities in which a call must traverse a firewall: when the VidyoGateway is
behind a NAT/firewall and when the Legacy device is behind a firewall.

When the VidyoGateway resides on the public network with a native public IP address and
when the Legacy device is behind a NAT/firewall, the Legacy device must open the required
H.323 or SIP ports (whichever are being used).
 When the VidyoGateway is behind a firewall and/or within a DMZ, you must configure your
firewall with a STATIC NAT (an external IP address routed to the VidyoGateway native private
address) and open the required ports in both directions.
 Configure your NAT Public IP Address. For more information, see
Address.
The following diagram illustrates the call flow from a Legacy endpoint calling Vidyo users when the
VidyoGateway is behind a NAT/firewall.
Calling from Legacy in to Vidyo
VidyoGateway
5
Legacy
Device
The following list explains each number in the "Calling from Legacy to Vidyo" illustration above.
1. The Legacy device calls the VidyoGateway public-facing IP address.
2. The VidyoGateway sends commands to the VidyoPortal.
3. VidyoManager (on the VidyoPortal) sends the VidyoGateway the VidyoRouter address to
use for calls.
4. The VidyoGateway establishes a TCP session (17990) with the VidyoRouter. H.264 SVC
media streams (audio/video) are sent over UDP between the VidyoGateway and
VidyoRouter.
Private Public
2 4
192.168.1.110
(private address)
VidyoPortal
3
Internet
200.100.50.25
(public address)
1
Legacy
Device
173
Configuring a Public IP
VidyoRouter
Vidyo
User