You are the administrator for your company’s UCM network. Examine the exhibit below, and answer the
question:

Which of the following fields should you configure to enable calls from this Cisco Jabber client to be rerouted
through the PSTN if bandwidth is lacking?

A.
AAR Group

B.
Location

C.
Rerouting Calling Search Space

D.
SUBSCRIBE Calling Search Space

E.
Use Trusted Relay Point

Explanation:
You should configure the AAR Group field to enable calls from this Cisco Jabber client to be rerouted throughthe public switched telephone network (PSTN) if bandwidth is lacking. Automated Alternate Routing (AAR)
Group configurations enable calls to be rerouted to specified destinations when Cisco Unified Communications
Manager (UCM) blocks a call because bandwidth is lacking. AAR Group profiles are configured by navigating to
Call Routing > AAR Group in UCM Administration. After you have configured a profile, you can assign it to an
endpoint by selecting the profile from the AAR Group dropdown field on the Device > Phone configuration page
for the given endpoint.
You should not configure the Location field. The Location field is used to configure call admission control
(CAC). CAC is used to limit bandwidth available for audio and video calls between locations, thereby regulating
the quality of those calls. The location of Hub_None, which is used in this scenario, indicates that UCM is not
monitoring the bandwidth that this particular endpoint is using. Locations can be configured by navigating to
System > Location in UCM Administration. After locations have been configured, you can apply the
configuration to an endpoint by selecting it from the Location dropdown field on the Device > Phone
configuration page for the given endpoint.
You should configure neither the Rerouting Calling Search Space field nor the SUBSCRIBE Calling Search
Space field. A search space is an ordered list of partitions that a device is allowed to search for patterns that
match a given string, such as a dialed number. The Rerouting Calling Search Space field determines the route
to a refer to target. The target is specified in a Session Initiation Protocol (SIP) Refer message. The
SUBSCRIBE Calling Search Space field, on the other hand, is used to route Presence subscribe requests from
an endpoint.
You should not configure the Use Trusted Relay Point field. A Trusted Relay Point (TRP) is a transcoder or
media termination point (MTP) device that UCM considers to be the closest to a given endpoint if multiple
resources are required for the endpoint. When this option is configured to the Default setting, the endpoint uses
a common device configuration to determine the TRP setting. If this option is configured to Off, UCM will not
attempt to use a TRP for the endpoint regardless of the common device configuration. If this option is
configured to On, UCM will attempt to use a TRP for the endpoint regardless of the common device
configuration.

Cisco: Automated Alternate Routing Group Configuration