1. Unified Communication Manager 7.1(2) CTI Scalability Improvements
George Gary, Product Mgr.
IP Communications
July 2009

2. UC Application Enabled
Improved CTI coverage
Better CTI scalability for multi-line devices
Better CTI scalability for shared line devices

3. Definition of terms
Subscriber – a Unified CM cluster server running the CallManager and CTI Manager service for Cisco IP devices
CTI enabled Device – a Cisco IP Phone or Virtual device (CTI port, RoutePoint).
A list of CTI supported devices can be found:
CTI Provider – a single IP connection between the CTI application and the CTI Manager service running on a Subscriber
Non-CTI enabled Device – a Cisco IP Phone not enabled, associated, or used with a CTI application

4. CTI Scalability Improvements (Per Server)
Server Class
Unified CM 7.0(1) or earlier
Per Subscriber
Unified CM 7.1(2)
1 Application per device
Each device has 2 DNs or 3 shared lines
7825-H3/I3
800 CTI enabled devices,
200 non-CTI devices
1 CTI provider supports 800 devices
900 CTI enabled devices or 1,800 CTI-enabled lines (per Subscriber) whichever comes first
100 non-CTI devices
1 CTI provider supports 900 devices
7835-H2/I2
800 CTI enabled devices
1700 non-CTI devices
1,000 CTI enabled devices or 2,000 CTI-enabled lines (per Subscriber) whichever comes first
1500 non-CTI devices
1 CTI provider supports 1000 devices
7845-H2/I2
2500 CTI enabled devices
5000 non-CTI devices
1 CTI provider supports 2500 devices
3375 CTI-enabled devices or 6750 CTI-enabled lines (per Subscriber) whichever comes first
4125 non-CTI devices
1 CTI provider supports 3375 devices

5. CTI Scalability Improvements (Cluster Totals)
Server Class
Unified CM 7.0(1) or earlier
Assumes a 4 Subscriber cluster
Unified CM 7.1(2)
1 Application per device
Each device has 2 DNs or 3 shared lines
7825-H3/I3
3200 CTI enabled devices,
800 non-CTI devices
3600 CTI enabled devices or 7200 CTI-enabled lines whichever comes first (evenly distributed across a 4 subscriber cluster)
400 non-CTI devices
7835-H2/I2
3200 CTI enabled devices
6800 non-CTI devices
4000 CTI enabled devices or 16,000 CTI-enabled lines whichever comes first (evenly distributed across a 4 subscriber cluster)
6000 non-CTI devices
7845-H2/I2
10,000 CTI enabled devices
20,000 non-CTI devices
13,500 CTI enabled devices or 27,000 CTI-enabled lines, whichever comes first (evenly distributed across a 4 subscriber cluster)
16,500 non-CTI devices

6. CTI support for Multiple Lines
100% improvement
A single CTI resource can now support 2 CTI-enabled unique DNs (not shared) per device without requiring additional resources
Previously 1 CTI resource was required per unique DN
Device BHCA must not exceed 6
If device BHCA exceeds 6 or if the device is configured with 3 or more unique (not shared) CTI-enabled DNs, then additional CTI resources are required.
Use the Unified Communication Sizing Tool to determine the CTI resources required:

7. CTI support for Shared Lines
200% improvement
A single CTI resource can now support 3 CTI-enabled shared DNs per device without requiring additional resources
Previously 1 CTI resource was required per shared DN
Total Device BHCA across all lines on the device must not exceed 6
If the total device BHCA exceeds 6 or if the device is configured with 4 or more shared CTI-enabled DNs, then additional CTI resources are required.
Use the Unified Communication Sizing Tool to determine the CTI resources required:

8. Comparison of CTI Improvements with Cisco Unified Personal Communicator
Unified CM 7.0(1) or earlier
Unified CM 7.1(2) and later
7825-H2/I2 – 3200 clients
7835-H1/I1 – 3200 clients
7845-H1/I1 – 10,000 clients
7825-H3/I3 – 3600 clients
7835-H2/I2 – 4000 clients
7845-H2/I2 – 13,500 clients
Use the Unified Communication Sizing Tool to determine the CTI resources required: