Hi ross,
you can refer the discussion
https://supportforums.cisco.com/thread/2227236
you can the faq on ELM
https://supportforums.cisco.com/docs/DOC-27483
Q: What are the benefits of this licensing structure over the previous DLU structure?
A: The main benefits of using ELM are the following:
- You do not have to keep on calculating your assistants, such as how many DLUs you have based on which type of phones and how many are you going to use now. You can structure your user group as per the usability. You can have a pool of licenses and CUCM can pick as per the requirement. Licenses will be released if not being used. The licensing is more of user-based now according to the feature that has been used by the users. For example, you can have certain users in your office that need only a basic phone. There will be some users which need additional capability. This way you can separate your users into different groups and order the services or licenses accordingly.
- In case of VMWARE, use 8 to 9 parameters to generate a license MAC. Even if you change any one of the parameters, such as NTP Address or the Time Zone, the license MAC will change. Then, you need to procure new licenses. However, with this Enterprise License Manager in place, even if you made those changes you do not have to worry about the licenses. There is a product instance that has already been added to the ELM. Even if you make any changes, it will grab the required license from ELM.
- You can have multiple clusters added with one ELM
regds,
aman