How to detect TelePresence 1.7.4 QoS change in CallManager

[dgauthier]

TelePresence v1.7.4 with CUCM 8.0 introduced QoS settings for CTS endpoints.  From what documentation I have found...CTS SysOp messages would display a change...but the SysOp messages are only available via CTS endpoint GUI (as far as I can tell). 

Question.  Is there a way that the CTS endpoint could notify external NMS of the QoS setting change? Or does CUCM have something in RTMT that can create an email notification?  curious if there is a solution...thx.

[Tyler Wilkin]

Hi David,

Can you clarify what you need a little more? I can assume you're asking one of two things:

1. Notification of when the QoS settings are changed in CUCM -> Service Parameters for TelePresence. Since this would be a relatively large network setting change. I wouldn't imagine you would need a notification of this since it's something that would probably be set up just once.

2. Notification of when the QoS markings in the media received on the CTS change. I'm unsure there is a good way to monitor this because if it's based on what the CTS reports it would throw many false alarms. In certain situtations when the CTS isn't receiving media, it will actually report BE markings. For example, when a call is put on hold or the endpoint is the only participant in a multipoint meeting, we will sometimes see the markings change to BE when really there is no media at all.

Tyler Wilkin

TAC TelePresence

[dgauthier]

Tyler,

If a CTS endpoint is provisioned for CUCM, the QoS values provided by CUCM are dictated by Service Parameters, CallManager, Clusterwide Parameters (System – QoS) has a default ‘DSCP for TelePresence Calls’ of CS4.

So, if there was a mistake in change or perhaps malicious change in QoS value in CUCM, the CTS endpoint SysOp sees this change.  I was wondering if there was any easy way to be alerting in the QoS value change?

CUCM RTMT does not a perfmon counter flag to notifty this.  And the only way I was figuring perhaps CISCO-TELEPRESENCE-MIB...but I only see ctpPeripheralErrorNotification.

The SysOp QoS message is INFO as far as I can tell...so no sure if there is an easy way to noting the change other than physically eyeing thru logs or endpoint GUI/CLI to note the change.

[vinanjun]

Hi David

  The DSCP values you are seeing in the sysop logs are not altered by CTS codec since it is incapable of remarking the packets, and all the markings are based on cucm settings. All that it shows in the logs are the packets those are seen on the port the codec is receiving so you can see QoS values changing very often for various calls as it takes different network path.

There are no mechanism to notify the change in QoS  settings other then seeing in the CTS gui call statistics window for a  live call and in sysop logs. And under telephony seetings you can see the dscp values pushed by cucm.

[dgauthier]

V,

thanks for the response.  I agree that the CTS endpoint does not alter the QoS setting, i.e. remark packets, since the CTS endpoint is provided the CS4 setting from CUCM.

My question is really about if the CUCM provided CS4 value changes to CS3 (for example) what type of notification capability exists on CUCM or the CTS endpoint.  I know that CUCM does not have a method, nor does CUCM RTMT offer ability either.

I was hoping that thru CTS endpoint via syslog, i.e. snmpset command that there could be a way of getting notified.  I believe since the QoS in CTS endpoint show in SysOP as INFO...there is not viable method to obtain notification.  Only method is to view the CTS Manager GUI.