IPT Licencing

Unanswered Question
rob.huffman Sat, 11/29/2008 - 08:38

Hi Bongani,

You definately require DLU Licenses to run the IP Phones :)

Seats is related to the Number of Users. DLU's is related to the number, in total, of Devices x DLU/per Device. In CCM 5.x and above IP Phones require DLU's or Device License Units that must be purchased from Cisco;

Device licenses are required for Cisco devices and for third-party devices,with the flexibility to replace third-party devices with Cisco devices. Device licenses are sold in increments of device-license units (DLU's). Device-license units are assigned to each device connected to Cisco Unified CallManager 5.0. Each device is assigned a unit number based on the type and capabilities of the device. Devices with more complex and high-end capabilities are assigned a higher number of units compared to devices with basic capabilities,

From this good Q & A doc;



Application and phone software licenses are enforced. The system manages the maximum number of devices that can be provisioned.

• Each device (Cisco Unified IP phones, third-party devices, and video devices) provisioned in the system corresponds to a number of device license units (DLUs), depending on its capabilities; the total number of units is managed in Cisco Unified CallManager to determine capacity.

• DLUs must be purchased to cover the number of devices connected to Cisco Unified CallManager.

• Third-party SIP devices require DLUs for operation with Cisco Unified CallManager.

Here is the DLU breakdown;

Cisco Unified IP Phone 7902G = 1

Cisco Unified IP Phone 7905G = 2

Cisco Unified IP Phone 7911G = 3

Cisco Unified IP Phone 7912G = 3

Cisco Unified Wireless IP Phone 7920 (no battery) = 4

Cisco Unified IP Conference Station 7936 = 3

Cisco Unified IP Phone 7940G = 4

Cisco Unified IP Phone 7941G = 4

Cisco Unified IP Phone 7941G-GE = 4

Cisco Unified IP Phone 7960G = 4

Cisco Unified IP Phone 7961G = 4

Cisco Unified IP Phone 7961G-GE = 4

Cisco Unified IP Phone 7970G = 5

Cisco Unified IP Phone 7971G = 5

Cisco Unified IP Phone 7985G = 6

Third-party SIP device (basic) = 3 (third-party)

Third-party SIP device (advanced) = 6 (third-party


Here is the DLU Calculator;


Hope this helps!


Thanks for a quick response. Our client has a requireent for a solution using a SIP phone. The only SIP phone is the CP3911. How many DLU's does this one have? Is there a solution that you can think of that can provide for the usage of 550 SIP phones and be cost-effective? Are the DLUs based on each connected phone or used phone?

rob.huffman Sat, 11/29/2008 - 09:30

Hi Bongani,

You are most welcome! The DLU total is based on the connected or configured phones. The number for the 3911 is fairly reasonable, as you have to keep in mind that Cisco decreased the cost of the phone itself when this DLU licensing was introduced :)

The 3911 rquires 2 DLU's :)

Q. Is a station user license required?

A. Yes, the Cisco Unified SIP Phone 3911 requires two (2) Unified Communications Manager Device License Units.

From this good doc;


Hope this helps!



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