The following CTI-controlled device types exist:
Cisco Unified IP Phones (SCCP and SIP)
CTI applications support only some phones that run SIP; for
example, it does not support the
Cisco Unified IP Phone 7940 and 7960.
CTI route points
If a directory number (DN) is a member of a line group or hunt list,
any device (CTI port, CTI route point, phone that is running SCCP, or phone
that is running SIP) that uses that DN should not be associated with a CTI
CTI devices do not support the multicast Music On Hold feature. If a
CTI device is configured with a multicast MOH device in the media resource
group list of the CTI device, call control issues may result. CTI devices do
not support multicast media streaming.
Cisco Unified IP Phones
Cisco Unified IP Phones comprise phones that are running SCCP that a CTI application
can control. CTI supports SIP on the
Cisco Unified IP Phones (7911, 7941, 7961, 7970, and 7971) from the CTI interfaces
JTAPI and TAPI, with some limitations. CTI applications control and monitor
phones that are running SIP in the same manner as CTI-controlled/monitored
phones that are running SCCP.
For phones that are running SCCP, outbound dialing supports
enbloc (the phone collects all digits before passing them to
Cisco Unified Communications Manager for routing) or digit-by-digit collection. If
dialing is done digit-by-digit, a CTI dialing call state notification gets sent
to the phone when it goes off hook and the first digit is pressed for an
outgoing call. For enbloc outbound dialing, the dialing call state notification
gets delayed until the phone collects all the digits and sends them to
Cisco Unified Communications Manager for routing.
When an outbound call is pending on an SCCP device and is not yet connected, Cisco Unified Communications Manager does not process call setup requests for that device until the first call is connected. If you are using a CTI application for outbound dialing, Cisco recommends that you configure an interval between outbound calls to ensure that pending calls are connected before new call requests are initiated.
For phones that are running SIP, enbloc dialing always gets
used even if the user first goes off hook before dialing digits; the phone will
wait until all the digits are collected before sending the digits to
Cisco Unified Communications Manager. This means that the dialing call state
notification will only get generated after enough digits are pressed on the
phone to match one of the configured dialing patterns. In all cases, the
dialing state notifications will always get generated prior to the call being
routed to the destination (as is the case with phones that are running SCCP).
Phones that are running SIP control when and how long to
play reorder tone. When a phone that is running SIP receives a request to play
reorder tone, it releases the resources from
Cisco Unified Communications Manager and plays reorder tone. Therefore, the call
appears to be idle to a CTI application regardless of when reorder tone is
played on the phone. In these scenarios, applications can receive and initiate
calls from the phone regardless whether reorder tone plays on the phone.
Because resources have been released on
Cisco Unified Communications Manager, the call does not count against the busy
trigger and maximum number of call counters (that are configured on the
Directory Number Configuration window).
Cisco Unified IP Phones with SIP that are configured to use UDP as the transport mode
(instead of TCP) do not support the device data pass-through functionality; for
example, the Quality Reporting Tool (QRT) requires the data pass-through
functionality, so it cannot be used with IP phones that are configured with
CTI ports as virtual devices can have one or more virtual
lines, and software-based
Cisco Unified Communications Manager applications such as
Cisco IP Softphone,
Cisco Unified Communications Manager Auto-Attendant, and Cisco Unified IP Interactive Voice
Response (IVR) use them. You configure CTI ports by using the same
Cisco Unified Communications Manager Administration windows as you use to configure
phones. For first-party call control, you must add a CTI port for each active
CTI Route Point
A CTI route point virtual device can receive multiple,
simultaneous calls for application-controlled redirection. You can configure
one or more lines on a CTI route point that users can call to access the
application. Applications can answer calls at a route point and can also
redirect calls to a CTI port or IP phone. When a CTI application requests to
redirect a call by using the Redirect API,
Cisco Unified Communications Manager uses the configuration for the line/device
calling search space for the redirected party.
Route points can receive multiple, simultaneous calls;
therefore, applications that want to terminate media for calls at route points
must specify the media and port for the call on a per-call basis. CTI route
points support the following features:
Answer a call
Make and receive multiple active calls
Redirect a call
Hold a call
Unhold a call
Drop a call
When a call arrives at a route point, the application must
handle (accept, answer, redirect) it within a specified time. To configure the
time that is allowed to answer a call, use the Cisco CallManager CTI New Call
Accept Timer service parameter. Use the Directory Number Configuration window
Cisco Unified Communications Manager Administration to configure the number of
simultaneous active calls on the route point.
If you are planning to use a TAPI application to control CTI port
devices by using the Cisco CallManager Telephony Service Provider (TSP), you
may only configure one line per CTI port device.
Applications that are identified as users can control CTI
devices. When users have control of a device, they can control certain settings
for that device, such as answer the call and call forwarding.
CTI devices (CTI ports, CTI route points) must associate
with device pools that contain the list of eligible
Cisco Unified Communications Managers for those devices.
The maximum number of CTI-controlled devices per node varies
by server class as follows:
MCS-7825 and MCS-7835 servers support up to 800 CTI-controlled
devices per node.
MCS-7845 servers support up to 2500 CTI-controlled devices per
When a CTI device fails (during a
Cisco Unified Communications Manager failure, for example),
Cisco Unified Communications Manager maintains media streams that are already
connected between devices (for devices that support this feature).
Cisco Unified Communications Manager drops calls that are in the process of being
set up or modified (transfer, conference, redirect, and so on).