VT2442 call priority

Posts: 10 · Vonage Forum Associate Joined: Feb 23, 2008 Posts: 10

I have a VT2442 phone adapter/router combo in a
dsl modem->VT2442->PC configuration.

The phone quality is fine as long as I'm not doing any internet activity on the PC.

If I go to a web site while on the phone the person I'm talking with says the call gets very choppy and it returns to normal when the web page loads. If I try to send an email while on the phone the call quality gets so bad the call often drops.

Should the VT2442 give priority to the phone ? Is there a setting I can change to give the phone call priority ?

My download/upload speed to 10mbps/768 kbps

Posts: 86 · Vonage Forum Senior Joined: Jan 03, 2009 Posts: 86

What DSL modem make and model
what are your pingtest.net line quality score?

Posts: 10 · Vonage Forum Associate Joined: Feb 23, 2008 Posts: 10

DSL-MODEM: Comtrend CT-5071T

Line Quality: A
Ping: 26ms
Jitter: 2ms
MOS: 4.39
Packet Loss: 0%

Out of interest when I repeated the pingtest while on a call the call got knocked down. When I had UltraVNC going and had a friend view my desktop I was uploading at 30kbps and no call degradation. When I went to www.t-mobile.com my friend said the call was choppy until the t-mobile site finished loading. So could it be browser activity that's causing the problem ?

Posts: 86 · Vonage Forum Senior Joined: Jan 03, 2009 Posts: 86

I am not familiar with the CT-5071T

CT-5071T

Posts: 830 · Vonage Forum Evangelist Joined: Jun 08, 2007 Posts: 830

AndyPopely wrote:

DSL-MODEM: Comtrend CT-5071T

Line Quality: A
Ping: 26ms
Jitter: 2ms
MOS: 4.39
Packet Loss: 0%

Out of interest when I repeated the pingtest while on a call the call got knocked down. When I had UltraVNC going and had a friend view my desktop I was uploading at 30kbps and no call degradation. When I went to www.t-mobile.com my friend said the call was choppy until the t-mobile site finished loading. So could it be browser activity that's causing the problem ?

Strange . . . as I have had no prblems with my VT2142 except when upoading via terminal services . . . then its a disaster!

Posts: 10 · Vonage Forum Associate Joined: Feb 23, 2008 Posts: 10

I've pretty much proven that the choppy call is being caused by the maximum upload bandwidth being reached.

So does it suggest the VT2442 does not ensure there's enough upload bandwidth for the phone ?

Posts: 86 · Vonage Forum Senior Joined: Jan 03, 2009 Posts: 86

AndyPopely wrote:

Should the VT2442 give priority to the phone ? Is there a setting I can change to give the phone call priority ?

The Comtrend CT-5071T woud be the appliance that would provide "priority" also known as Quality of Service (QoS)

A i said I am not familiar with the Comtrend CT-5071T. But with other Gateways that have similar options you need to turn the SPI (Stateful Packet Inspection) off as-well-as DoS protection and any Voip or SIP application layer gateway (ALG)/Application Passthrough

link to CT-5071T specs

More

Posts: 10 · Vonage Forum Associate Joined: Feb 23, 2008 Posts: 10

As fate would have it the Comtrend modem died and I replaced it with a Diamond Supra Max modem. As the VT2442 is also a router both modems were/are bridged. The choppy phone quality occurs likewise with the Supra Max modem when I'm uploading a file. Even when the upload bandwidth hasn't been reached the call is still choppy.

So my question for those Vonage users who use the V-Portal VDV21-VD in a modem -> v-portal -> any router -> p.c. configuration do you experience choppy phone calls when uploading files ?

Posts: 830 · Vonage Forum Evangelist Joined: Jun 08, 2007 Posts: 830

AndyPopely wrote:

I've pretty much proven that the choppy call is being caused by the maximum upload bandwidth being reached.

I think AndyPopely is correct. DSL may be more consistant, but has lower bandwidth, and if you are maxing it out, priority does little or nothing.

Posts: 10 · Vonage Forum Associate Joined: Feb 23, 2008 Posts: 10

Well I implemented a change to the VT2442 Vonage adapter/router which has improved the call quality while a file upload is in progress.

I added UDP ports 10000 thru 20000 to the source and destination ports category in the IP QOS section of the VT2442 with a priority of high.

This is based on the recommendation from Vonage for adapters.

http://www.vonage.com/support.php?article=1098

I would have thought this was unnecessary on a built in adapter.

So the test was to be on a call while uploading a file.

The result before I made the change was the person on the other end could hardly hear me at all because my voice kept cutting out and sometimes the call would drop all together.

The result after I made the change was the person on the other end could hear me with no cutting out just my voice would warble at times.

Please let me know if there's anything else that can be done to improve the call quality ....