R2511-HP MSR Router Series Voice Configuration Guide(V5)

17
Configuring fast connection and tunneling
Fast connection and tunneling
• According to the specification of H.225.0 recommendation, fast connection means that a Setup,
CallProceeding, Alerting, or Connect message carries a standard H.245 message (for example,
Open Logical Channel message) so that an RTP/RTCP voice channel can be established before the
gateway (GW) receives a Connect message, avoiding H.245 message exchange on TCP
connection, and thereby shortening connection time. There is no capability negotiation process in
fast connection mode, so the capability of both parties is determined by the terminating GW. When
fast connection is enabled, a Setup message sent from the originating GW carries locally
supported codecs. After receiving this message, the terminating GW selects one suitable codec to
notify the originating GW through a CallProceeding, Alerting, or Connect message. In this way,
both parties adopt this codec for communication.
• Tunneling means that in fast connection mode, non-standard H.245 messages (for example,
transparent transmission capability of DTMF digit) are encapsulated in an H.225.0 Facility
message to complete capability negotiation and call forwarding. This makes it unnecessary to
establish an independent H.245 TCP connection for transmission of H.245 message.
Enabling fast connection and tunneling on the originating GW
Step Command Remarks
1. Enter system view.
system-view N/A
2. Enter voice view.
voice-setup N/A
3. Enter voice dial program
view.
dial-program N/A
4. Enter VoIP voice entity
view.
entity entity-number voip N/A
5. Enable fast connection.
fast-connect Disabled by default.
6. Enable the local end to
play ringback tones.
send-ring
Optional.
In the fast connection mode, the remote
end plays ringback tones by default.
This command is available on an H.323
voice entity only after fast connection is
enabled for it.
If you want the local end to play ringback
tones, carry out this command.
7. Enable tunneling.
tunnel-on
Optional.
Disabled by default.
This command is applicable only after the
fast connection is enabled.
Enabling fast connection and tunneling on the terminating GW
You can enable or disable fast connection for each outgoing call on the originating GW. If fast
connection is enabled on the originating GW, the terminating GW will determine whether to enable fast
connection for call initialization or enable tunneling, depending on the configurations of the voip
called-start and voip called-tunnel enable commands.
To enable fast connection and tunneling on the terminating GW: