Showing results for 
Search instead for 
Did you mean: 

Spark Room Endpoints Conferencing with CUCM Registered Endpoints(on Prem)



How can I have a video conference between Spark Cloud registered endpoints (like Room 55 and 70) with CUCM registered on-prem endpoints like IX5000.

For the Spark Cloud registered endpoints we are also using Cisco Hybrid Media Node (HMN). I do understand that HMN will be supporting video conferencing with on-prem CUCM registered endpoints (road-mapped) but trying to understand if we need any other components in the mix or is it just a s/w upgrade on HMN that will enable the on-prem bridging capability.

Appreciate any responses in advance.


Ari Cisco’s Hybrid Media Node (HMN)? Hybrid Media Node (HMN)? Cisco’s Hybrid Media Node (HMN)?

22 Replies 22

Yes see here



Perfect Srini, exactly what I was looking for. I didn't think it would be an issue, but needed confirmation all the same.

Thanks, Steven

One caveat with HMN, Video call back using WebEx isn’t supported, that will come from the cloud. However if you dial into WebEx SIP URI, that will use HMN, make sense?

Srini Kilambi

UC Solution Architect | CDW

Many thanks again for pointing this out and yes that does make sense Srini.



To follow up on Ari's question:

An enterprise has one CUCM cluster deployed at a large campus with video endpoints registered directly to the on-prem CUCM cluster. There is also an on-prem HMN for keeping video media streams local to the large campus. The same enterprise has global presence with offices located in various world regions where video endpoints register directly to Spark (due to the lack of the enterprise CUCM clusters in other regions).  

The goal is to be able to conduct WebEx meetings among video endpoints registered to CUCM, video endpoints registered to Spark, and WebEx users participating from their workstations/laptops/tablets/smartphones.

1. Is it possible to conference the two environments via WebEx: video endpoints registered to the on-prem CUCM (with on-prem HMN) and video endpoints registered to Spark?

2. Would the video endpoints registered to CUCM get OBTP for such WebEx meetings?

3. Would the video endpoints registered to Spark get OBTP for such WebEx meetings?

4. Can such WebEx meetings be scheduled via MS Exchange, and if so, is TMS required for the scheduling integration via MS Exchange?

5. Is TMS required for OBTP?

Thank you.

1) Sure both can dial SIP URI, you can join WebEx from spark client using calendar connector as an example or from a spark video endpoint

2) Yes via TMS

3) Yes you can get OBTP with calendar connector

4) PT tools or Calendar connector both provide exchange scheduling. Calendar connector is needed for spark endpoints to get OBTP. PT tools can do it for on premise endpoints for exchange schedulng. TMS is needed for CCM endpoints not for spark since you will use @webex with calendar connector for OBTP

Deployment Guide for Cisco Spark Hybrid Calendar Service - Cisco

5) See above

Thanks, Srini.

I have follow-up questions:

#2 above. Can CUCM registered endpoints get OBTP without TMS?

Here's my thinking:

a. Calendar Connector running on Expressway will sync the scheduled WebEx conference (via PT or @webex) from Exchange to Spark.

b. Can this WebEx conference be pushed from Spark to CUCM-registered endpoints using the on-prem HMN as a proxy between Spark and the on-prem CUCM? I guess, maybe CUCM can push OBTP to video endpoints that are registered with it?

It makes no sense at this point to maintain TMS because the only function that is being leveraged in TMS is OBTP for CUCM-registered endpoints. Every other TMS function has been obsoleted in this environment. TMS is no longer making the conference hardware resource reservation because the only on-prem conference resource - HMN - will automatically escalate to CMR-C if it runs out of conference resources. TMS is not doing WebEx conference reservation, since it's done by Exchange,  using PT or @webes. TMS-based provisioning is not leveraged anymore. TMS-based endpoint monitoring can be performed by another SNMP monitoring tool. What is the point in continuing to deploy TMS, which seems to be the only remaining Windows based service?

I know you are in close communication with Cisco. Unless it's subject to NDA, could you shed some light on whether Cisco is planning to provide OBTP for CUCM-registered endpoints without TMS any time soon? IMHO TMS has got to go.

Thank you again.


Very valid points and one that does keep coming up on the demise of TMS. At this point it remains a need for CCM endpoints for OBTP.

Cisco response is that why cloud is better since it does this for you without TMS.

The expressway C today is needed with on premise exchange and O365 but not for google mail. So the plan is even with O365 to remove it so spark endpoints will have nothing on premise in the right scenario

So the cloud architecture is being recommended versus on premise and I don’t know of roadmap to remove it for on premise

However while all of the ones below may not be as elegant as TMS it’s worth looking at it

1) If the users use the same rooms for joining a WebEx they can enter the sip uri in their WebEx profile to allow them to join without trying to remember what the sip uri is. You can enter like 5 or so uri in your profile as favorite

2) Program some favorites of commonly used CMR rooms in the touch 10 (Has some obvious caveats like scale)

3) Use the new capability of proximity to learn the sip uri of the endpoint via the pc. This of course requires proximity to be not blocked on the network since it uses on prem proximity and not the one in spark

So the point is to get around TMS but also keep in mind TMS licensing isn’t super expensive and also included in certain licensing levels such as cuwl pro(now eol), cuwl meetings, flex EA and traditional EA based on how it was sold



Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Recognize Your Peers