H3C XE 200 IP, Operation Manual

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Operation Manual – Location Server Configuration
H3C XE 200/2000 IP PBX
Chapter 2 NAT/FW Tunnel Traversal
2-4
3) The PS in the private network establishes a TCP tunnel and a UDP tunnel
between itself and the PS in the public network using the tunnel configuration
information.
I. Tunnel traversal between private and public networks using XE IP PBXs
As shown in Figure 2-3 , the PS on XE IP PBX 1 and the voice gateway H.323 Gateway
1 reside in a private network. The PS on XE IP PBX 2, the voice gateway H.323
Gateway 2, and the LS on XE IP PBX 3 reside in a public network. A NAT/FW is
deployed between the private network and the public network.
Private Network
Public Network
NAT/FW
H.323 Gateway 1 H.323 Gateway 2
XE IP PBX 1
(Process Server)
XE IP PBX 2
(Process Server)
XE IP PBX 3
(Location Server)
Tunnel 1
Tunnel 2
Tunnel 3
Figure 2-3 Diagram for tunnel traversal between public and private networks using XE
IP PBXs
Tunnel traversal between the private network and the public network using XE IP PBXs
is implemented as follows.
The LS on XE IP PBX 3 opens a TCP port for listening and receiving TCP connection
request when the LS starts.
2) The PS on XE IP PBX 1 establishes a tunnel (Tunnel 1) between itself and the LS
on XE IP PBX 3 when the PS starts. This tunnel traverses the NAT/FW and is used
for the signaling exchange between the PS and the LS.
3) The LS on XE IP PBX 3 issues the configuration information about the tunnels to
be established between the PSs in the private network and the public network to
the PS on XE IP PBX 1 and the PS on XE IP PBX 2.
4) The PS on XE IP PBX 1 establishes a TCP tunnel (Tunnel 2) and an UDP tunnel
(Tunnel 3) between itself and the PS on XE IP PBX2. Both the tunnels traverse the
NAT/FW.
5) When establishing a call connection, H.323 Gateway 1 exchanges H.323 call
control signaling, H.323 media channel control signaling, or SIP signaling with
H.323 Gateway 2 through the TCP tunnel (Tunnel 2) established between the PS
on XE IP PBX 1 and the PS on XE IP PBX 2.