nerdexam
Cisco

300-085 · Question #217

The system administrator has successfully integrated Cisco Unity Connection over a WAN with Cisco Unified Communication Manager using SIP. When a call to a subscriber is forwarded to voicemail. the…

The correct answer is A. The telephone carrier is not preserving RDNIS across the network. When AAR reroutes calls via the PSTN during a WAN oversubscription event, the telephone carrier strips RDNIS, so Unity Connection cannot identify the target subscriber mailbox and defaults to the auto attendant.

Cisco Unity Connection

Question

The system administrator has successfully integrated Cisco Unity Connection over a WAN with Cisco Unified Communication Manager using SIP. When a call to a subscriber is forwarded to voicemail. the caller correctly hears the subscriber greeting. During a recent WAN oversubscription event, instead of routing the calls via SIP directly to Unity Connection, the AAR feature was used to route the calls via the PSTN to Unity Connection This worked, however on forwarded calls, the caller no longer heard the subscriber's greeting, but rather an auto attendant message that asked them to enter the extension of a party they want to reach. Which cause of callers not hearing the correct subscriber greeting is most likely true?

Options

  • AThe telephone carrier is not preserving RDNIS across the network
  • BAAR System Setting is not enabled in Unity Connection.
  • CUnity Connection Restriction Tables is not permitting calls via the PSTN
  • DDTMF is not negotiated properly on this call

How the community answered

(24 responses)
  • A
    63% (15)
  • B
    4% (1)
  • C
    13% (3)
  • D
    21% (5)

Why each option

When AAR reroutes calls via the PSTN during a WAN oversubscription event, the telephone carrier strips RDNIS, so Unity Connection cannot identify the target subscriber mailbox and defaults to the auto attendant.

AThe telephone carrier is not preserving RDNIS across the networkCorrect

RDNIS (Redirected Dialed Number Identification Service) carries the originally dialed subscriber extension from the PSTN to Unity Connection so it can locate the correct mailbox and play the personal greeting. When AAR reroutes calls through the PSTN, the carrier typically strips or does not forward RDNIS, leaving Unity Connection unable to identify the intended subscriber. Without RDNIS, Unity Connection falls back to the auto attendant and prompts the caller to dial an extension manually.

BAAR System Setting is not enabled in Unity Connection.

The AAR System Setting in Unity Connection controls whether the AAR feature itself is enabled, not how Unity Connection identifies which subscriber mailbox greeting to play once the call has already arrived.

CUnity Connection Restriction Tables is not permitting calls via the PSTN

Unity Connection Restriction Tables govern which numbers Unity Connection is permitted to dial outbound, not how incoming PSTN calls are matched to subscriber mailboxes; the calls were still arriving successfully.

DDTMF is not negotiated properly on this call

DTMF negotiation affects whether touch-tone key presses are recognized during an active call, not the initial routing of a forwarded call to the correct subscriber greeting.

Concept tested: RDNIS preservation for voicemail subscriber greeting routing

Source: https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/connection/10x/design/guide/10xcucdg/10xcucdg020.html

Topics

#RDNIS#AAR routing#PSTN failover#voicemail greeting routing

Community Discussion

No community discussion yet for this question.

Full 300-085 Practice