Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

Ho many people can join on conference 6945????

Hi all,

We are using call manager 9.1 and we have 6945 series IP phone and we have noticed we can bring only 15 people in conference is there any way we can bring more then 50 people in conference? is it possible?

Do we need any aditional hardware? on Voice gateway router if yes could any one help me with guide or document

also I wanted to know what is the difference between Meetme conf and normal conf on the ip phone.




Ho many people can join on conference 6945????


The CUCM Call Manager service has two service parameters that control the maximum number of parties allowed in a conference. One paramter is Maximum Ad Hoc Conferences and the second is Maximum MeetMe Conference Unicast. The maximum value for the Ad Hoc option is 64 and the maximum for the MeetMe option is 128.

If you are using G.711 exclusively then you do not require any DSP hardware. You can leverage the software resources on any CUCM node running the IPVMS service in your cluster. However, if you are running IPVMS on a cluster node that is also running the Call Manager service then you want to be careful because heavy media processing can disrupt standard call processing.

In addition, there is a separate set of service parameters to deal with if using the software media resources on a CUCM node. The service that controls all of this media stuff is the IP Voice Media Streaming (IPVMS) service. This service has a parameter that controls the maximum number of streams you can support with conferencing. The default value is 48 and Cisco states that you should only increase that value if you are running a cluster configuration where you have dedicate media processing (IPVMS) nodes. The maximum value is 256 streams and, as previously noted, this only support G711.

Personally, I hardly ever use software resources for conferencing. So, given the size you are talking, I would be inclined to ether adding a node to the cluster for media processing or leverage hardware DSP resources on a ISR. Sizing DSPs is a long talk in and of itself. I suggest reading:

The above will give you an overview of DSP options in the latest ISRs.

The difference between Meet Me and Adhoc conferencing is that the former allows a phone user to "open" a conference line that other callers can dial into. The latter is basically an enhanced 3-way call (with more than 3-ways). The Meet Me conference MUST be initiated by an IP phone registered to the CUCM cluster (i.e. "on-net"). Folks calling into the MeetMe Line (MML) can be on-net or off-net.


(t) @ucguerrilla

Please remember to rate helpful responses and identify helpful or correct answers.

HTH -Bill (b) (t) @ucguerrilla

Please remember to rate helpful responses and identify

Ho many people can join on conference 6945????

Hi Rebecca,

In CUCM conferences may be hosted by the CUCM server (software conferences) or by PVDM modules in a router (hardware conferences). - there some other options but these are the most common.

The maximum number of participants varies by where the conference is hosted and can be modified using CUCM service parameters and/or IOS commands under the SCCP conference profile on the router.

It is normally preferable to host conferences on PVDMs as it removes load from the CUCM servers and provides support for a wider range of codecs. However the software conference may be the best option for you as is can support more participants as long as using G711 codec is ok for you.

Review the service parameters, Maximum Ad hoc Conference and the Maximum MeetMe Conference Unicast, and set to match the number of users you need in the conference. Also be careful as this can put a big load on your CUCM servers. If possible dedicate a CUCM server to running the conferences if you are going to host large conferences regularly.

Cisco Employee

Ho many people can join on conference 6945????

Just bear in mind that what you're asking for (50+ conferencees), will in fact make only 3 conferences available at any given time for each CFB you have, as the resources are reserved, and you only get 128 streams total per CFB.

If you want 50 people on a conference, and to use DSPs, you'll need PVDM3 and to use only G711 to reach that count (64 max)



if this helps, please rate



if this helps, please rate
CreatePlease login to create content