Dropped calls and the Jitters

[ipandy]

I have inherited 4 systems sitting at 6.0.14 (W,E,N, and O)all connected via SCN and all with IP telephones (NO DIGITAL AT ALL). W is the main system w/ VMPro, CCR, and 2 PRI's. The licensing is as follows:
W has 12 Virtual Avaya IP Endpoints, 52 Avaya IP Endpoints, 24 IP500 Voice Networking Channels, and everything else for CCR and VMPro.
O has 12 Virtual Avaya IP Endpoints, 43 Avaya IP Endpoints, 16 IP500 Voice Networking Channels, as well as 16 additional PRI licenses as they have a PRI as well.
N has 12 Virtual Avaya IP Endpoints, 45 Avaya IP Endpoints, 16 IP500 Voice Networking Channels.
E has 23 Avaya IP Endpoints, 8 IP500 Voice Networking Channels. This site doesn't have a VCM card installed in it which I think is why I don't have the 12 Virtual IP Endpoints.
Here are my problems. I have been getting a lot of complaints that external calls have a lot of noise on them, they are getting dropped, and the users are having problems transferring callers to other sites. W has a call center that handles call routing for the most part as well as the VMPro with an AutoAttendant. When I look at the System Status I notice on the Quality of Service that there are a lot of entries and Line 2 (one of the PRI's) is in most every one of them. I have many entries with the Jitters and some with Packet loss. We are having a meeting with the LEC tomorrow about the problem on this PRI but I didn't know if there is something else I am missing. The System Status is also giving me an error in the Service Tab of "Attempt to use a feature for which no license is installed. License Type: VCM Channel Migration"
Please let me know what you think.

 

[NYSTECH]

The point is probably mute but, do you know if a network assessment was done?
System Status is a good tool to get you pointed in a direction but, it isn't always accurate...
Some things to check on PRIs if you getting errors.. One of the PRI timming should be off the network othe should be fallback or unsistanable.. ( I think with 6.0.14 version you could use system monitor to look at errors on PRI.. check for slips and errors..etc.)

As far as the packet loss and jitter.. what kind of connection between the sites.. VPN or point to point?

You can try doing pings between sites and see if you loose any.. that should get you started

 

[ipandy]

Don't know about network assessment. I'll look at PRI clocks tonight. Going to do a system reboot to see if I can clear some gremlins. Connections between sites is P2P. I can ping other sites no problem with no packet loss and very short travel time.

I will look at sys monitor to see what it looks like.

 

[amriddle01]

Ping is a very poor indicator of potential QoS issues though, watching calls live in SSA/monitor and looking at the jitter etc then is best, or even on the hansets themselves

 

[amriddle01]

I should ad you can't get packet loss and jitter on a PRI as it isn't packetised data, are you sure those errors are showing against that line and not just that the line happened to be one leg of the call

 

[NYSTECH]

Look at your router interafces for the Point to Points see if you see errors on them.

 

[Morrack]

Determine if you have any trouble with site to site internal extension calls. Dial an extension at one of the sites from the central site, and stay on the call for a while. If you experience trouble on that call then the PRI is probably not guilty.

You need to ensure that every single network device from end to end supports QOS, and that it has been correctly configured. Otherwise you will get voice quality issues every time there is contention for network bandwidth.

After you've checked that, you may want to consider using some network monitoring tools. IXChariot and Solarwinds Orion are great, and they have free trials.


Peter Sherwood
Morrack Consulting
Affordable World Class Off-site Backup!

http://www.morrack.com