Yealink VC110 - Intelligent Firewall Traversal

Configuring Network
99
Intelligent Firewall Traversal
The intelligent firewall traversal feature allows the VC110 endpoint to check the media source
address and port of incoming RTP packets, and then send back RTP packets to the address
where incoming RTP packet comes from, instead of the address provided in the Session
Description Protocol (SDP).
The following example illustrates a scenario for using intelligent firewall traversal:
The device A is located in the Intranet and the router does not support the ALG feature. The
device B is located in the public network. A calls B, and then A sends the RTP packets to the B.
- If B enables the intelligent traversal feature, B sends back RTP packets to the address where
incoming RTP packet comes from. A and B can communicate normally.
- If B disables the intelligent traversal feature, B sends RTP data to the private IP address of A,
causing the device display of A appears black screen. To solve this problem, you need to
enable the static NAT feature on the A device and configure the port mapping on the
router.
The intelligent firewall traversal parameter is described below:
Parameter
Description
Configuration Method
Audio&Video
Intelligent Traversal
Enables or disables the Audio&Video
media stream to traverse firewall.
Default: On
Web User Interface
Data Intelligent
Traversal
Enables or disables the PC content and
FECC protocol to traverse firewall.
Default: On
Web User Interface
To configure intelligent firewall traversal via web user interface:
1. Click on Network->NAT/Firewall.
2. Select the desired value from the pull-down list of Audio&Video Intelligent Traversal.