Which statement describes DTMF processing on Cisco Unified Contact Center Express with
supported SIP-based agent IP phones that are registered to Cisco Unified Communications Manager?
A.
Cisco Unified CCX receives the DTMF digits via SIP NOTIFY messages.
B.
Cisco Unified CCX receives the DTMF digits in the RTP payload based on RFC 2833.
C.
Cisco Unified CCX receives the DTMF digits via JTAPI messages.
D.
Cisco Unified CCX receives the DTMF digits via SIP INFO messages.
E.
Cisco Unified CCX receives the DTMF digits as part of the audio encoding in the RTP stream.
Explanation:
Unified CCX CTI ports are notified of caller-entered digits (DTMF input) via JTAPI messages from
Unified CM. Unified CCX does not support any mechanism to detect in-band DTMF digits where
DTMF digits are sent with voice packets. In deployments with voice gateways or SIP phones that only
support in-band DTMF or are configured to use in-band DTMF, an MTP resource must be invoked by
Unified CM to convert the in-band DTMF signaling so that Unified CM can notify Unified CCX of the
caller-entered digits. Be sure to enable out-of-band DTMF signaling when configuring voice gateways
in order to avoid using the previous MTP resources.http://www.cisco.com/en/US/docs/voice_ip_comm/cust_contact/contact_center/crs/express_9_02
/design/guide/UCCX_BK_C39FDB35_00_cisco-unified-contact-center-express_chapter_010.html
SIP Support
Unified CCX agents may use Unified CM Session Initiation Protocol (SIP) phone models 7941, 7961, 7970,
and 7971. The 7940 and 7960 phones do support SIP with Unified CM 5.x and 6.x but may not be used for
Unified CCX agents (because the necessary third-party call control and monitoring required is not present).
The lower-end phone models are also not available to be used as SIP phones for Unified CCX agents. SCCP
support for Cisco IP Phones continues to be supported for agent phones.
Unified CCX CTI ports are notified of caller-entered digits (DTMF input) via JTAPI messages from Unified
CM. Unified CCX does not support any mechanism to detect in-band DTMF digits where DTMF digits are
sent with voice packets. In deployments with voice gateways or SIP phones that only support in-band DTMF
or are configured to use in-band DTMF, an MTP resource must be invoked by Unified CM to convert the
in-band DTMF signaling so that Unified CM can notify Unified CCX of the caller-entered digits. Be sure to
enable out-of-band DTMF signaling when configuring voice gateways in order to avoid using the previous
MTP resources. For detailed design consideration related to DTMF handling, media resources and voice
gateway deployments, please refer the Cisco Unified Communications Solution Reference Network Design
(SRND).