Yealink VC400 Administrator's Manual page 99

If multi-level intranet network has deployed in your environment, and you experience the
4.
one-way audio or video problem, select Compulsory from the pull-down list of Route
Traversal to solve this problem.
Click Confirm to accept the change.
5.
To configure Static NAT for SIP account via web user interface:
Click on Account->SIP Account.
1.
Select StaticNat from the pull-down list of NAT Traversal.
2.
Configuring Network
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