SIP UA Configuration 2377ConfiguringOut-of-Band SIP DTMFCode Transmission ModeDuring the communication between caller and callee, dual tone multi-frequency(DTMF) codes can be transmitted transparently between them in two ways:in-band and out-of-band. In the in-band approach, DTMF is encoded in RTP voicepackets, and in the out-of-band approach, in SIP messages.To implement DTMF out-of-band transmission, you need to configure it for theVoIP entity on the calling UA and for the corresponding POTS voice entity on thecalled UA.Configuration prerequisitesThe configuration at the SIP server end is completed.Configuration procedureFollow these steps to configure the out-of-band SIP DTMF transmission mode:n For more information about the outband sip command, refer to “VoIP Overview”on page 2243.Configuring a Source IPAddressYou may specify a source IP address for the packets sent by the SIP UA. This sourceIP address is usually the address of a logical interface such as a loopback interfacebecause this type of interface is always up.Configuration prerequisitesThe configuration at the SIP server end is completed.Configuration procedureFollow these steps to configure a source IP address:Configuring a DomainName for the SIP UASIP addresses can be domain names or IP addresses. As IP addresses of SIP UAs aremore likely to change, domain name addresses are preferred where fixed SIPaddresses are desired.To do... Use the command... RemarksEnter system view system-view -Enter voice view voice-setup -Enter voice dial program view dial-program -Enter voice entity view entity entity-number { pots |voip }-Configure the out-of-band SIPDTMF transmission modeoutband sip RequiredInband mode is applied bydefault.To do... Use the command... RemarksEnter system view system-view -Enter voice view voice-setup -Enter SIP client view sip -Bind a source IP address to theUA to send packetssource-ip ip-address RequiredNo source IP address is boundby default.
