Yealink VC400 Administrator's Manual page 108

Administrator's Guide for Yealink Video Conferencing Systems
TCP. Before the emergence of H.460, Enterprises have their own firewall/NAT traversal solutions,
which are incompatible with each other. Therefore, IP communication between enterprises is
difficult. H.460 resolves the compatibility problem.
H.460 enables H.323 signaling and media to traverse firewall. H.460 is a set of extensions to the
ITU H.323 standard that include methods to traverse firewalls. Devices that use H.460,
implement a set of security policies that a firewall is configurable to accept. Therefore using
H.460, video conferencing system can communicate across a firewall. You can configure the
system to use standard-based H.460.18 and H.460.19 firewall traversal, which allows the system
to establish IP connections across firewalls more easily.
The H.460.18 deals with signaling. The H.460.18 solution perpetually hunts in order to open
pinholes from the internal network to the external one. Without using the H.460.18 solution,
which permits the gatekeeper to open a connection, the external device could not communicate
with internal device, because the firewall would obstruct its attempt to setup a call. H.460.19
extends H.323 by defining the NAT/firewall mechanism for media. In addition, H.460.19 provides
a solution for opening RTP and RTCP pinholes and a method for maintaining them using a
keep-alive mechanism.
To use H.460, you need to deploy a Traversal Server (TS) at public network.
The following illustration shows how a H.460 traversal server works between two enterprise
locations.
The H.460 firewall traversal parameter is described below:
Parameter
H.460 Active
To configure H.460 firewall traversal for H.323 via web user interface:
Click on Account->H.323.
1.
92
Description
Enables or disables H.460 firewall
traversal feature on the system.
Default: Disabled
Configuration Method
Remote Control
Web User Interface