R0106-HP MSR Router Series Voice Configuration Guide(V7)
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Configuring source interface binding on a VoIP entity
Ste
p
Command
Remarks
1. Enter system view.
system-view N/A
2. Enter voice view.
voice-setup N/A
3. Enter SIP view.
sip N/A
4. Enter VoIP entity view.
entity entity-number voip N/A
5. Configure source interface
binding for outgoing SIP
messages or media packets.
voice-class sip bind { control |
media } source interface
interface-type interface-number
By default, the default global
source interface is used.
Configuring out-of-band DTMF
There are two ways to transmit DTMF tones: in-band signaling and out-of-band signaling. In-band
signaling sends DTMF tones in RTP packets, and out-of-band signaling sends DTMF tones in SIP
messages.
To use out-of-band signaling, configure the outband sip command on both the calling and called
devices.
To configure out-of-band DTMF:
Ste
p
Command
Remarks
1. Enter system view.
system-view N/A
2. Enter voice view.
voice-setup N/A
3. Enter dial program view.
dial-program N/A
4. Enter voice entity view.
entity entity-number { pots | voip }
N/A
5. Enable out-of-band DTMF.
outband sip
By default, inband DTMF is
enabled.
Configuring periodic refresh of SIP sessions
If a proxy server fails to receive a BYE message, it will always retain the state for the session. To solve this
problem, RFC 4082 defines a session refresh mechanism, which periodically sends re-INVITE or UPDATE
requests (referred to as refresh requests) to notify the proxy server of the current session state. The refresh
interval is determined through negotiation between the SIP UA and the SIP proxy server.
Session refresh uses two header fields Session-Expires and Min-SE, and a 422 response:
• Session-Expires—Conveys the maximum session expiration time. If no refresh request is received
within this time, the session is considered ended.
• Min-SE—Conveys the minimum session expiration time, which is used to avoid frequent refresh
requests from occupying excessive network bandwidth.
• 422 response—When a UAS or SIP proxy server receives a request in which the Session-Expires
field conveys a value smaller than the local Min-SE value, the UAS or SIP proxy server sends a 422
response that contains the local Min-SE value to notify the requesting party of the minimum session
expiration time.