BCM 50 remote office poor quality on conversations

[ljclives]

BCM 50 at site A with four trunks and 10 digital sets. Site B has three IP phones. There is of course a VPN between the two - SonicWalls at each end. Time Warner business class is the provider; 7 mg download speed and .768 upload. The quality on conversations between the two is choppy quite often; especially when site B is on a trunk call. The IT tech says he has done everything he can do. I am at a loss for I know nothing in the BCM to change to narrow this down. Any ideas on how to prove what the real issue is? Thanks in advance.

 

[gwebster]

Bandwidth is only part of the equation. High quality voice is dependent upon having voice packets arrive in a short period of time after being sent and with a consistent interval. Both packet delay (how long it takes) and jitter (variability) are the major contributors to poor voice quality. QoS mechanisms which can be implemented over your private network help to limit those impacts. You do not have the same control over the public/WAN network.

 

[ljclives]

OK great. So do I need to contact SonicWAll and work with them on firewall settings? Their IT tech said he did everything he could with that. Anything I can look at in the BCM?

 

[oldestgeek]

You could set them to use g,729 rather than the default g.711. That will decrease the bandwidth each call uses.

 

[bluemr2]

is this a vpn across the internet or a private circuit? if its across the internet there might not be anything you can do.

 

[ljclives]

Across the internet. I have the same setup with another customer and they have slower speeds and less bandwidth - no problem!

 

[bluemr2]

Bandwidth is not a measure of speed, it's a measure of capacity. Voice calls are relatively small, so VOIP issues are typically a problem with latency. Packets that travel across the internet go through multiple routers to get to you. Each of those routers may, but probably don't, expedite voice packets. Once those packets leave your edge router to the cloud, you have no control over how long it will take to get to the other router. In fact, net neutrality wants to mandate ISP's can't expedite some packets over others.

 

[dibthree]

Voice calls across the internet are always best effort. There is no way to control QOS. I have an IP phone at my house that connects to a BCM in our lab over VPN. It disconnects and reconnects a couple times a day on average. My call quality is good some days and bad others. But hey I cant complain. It's the open internet. What do you expect.

MPLS has gotten cheap. We replaced a 14 state VPN network with MPLS with QOS over the last year.

We went from voice calls being so problematic over the VPN WAN that no one used the site to site calling to perfect calls everytime over the MPLS Network.

Now if I could get the end users to stop complaining when their softphones dont work well from a hotel internet connection my life would be complete.