Softphone call quality

[as1981]

All,

I'm sure similar must have been asked before but I can't find anything in the search results.

I'm strugging to get a softphone running over adsl broadband. I'm aware that the upload speed is slower than the download. When I call another extension, be it internal phone or external number I get call break up.

I'm getting a consistent ping response of around 40ms from the IPO and an upload speed of 0.25mps. Should that be fast enough for VOIP?

Also, is it worth trying different codes or is auto an OK setting?

IPO 4.2 (14)
PC Manager 4.2.12

Thanks

Andrew

 

[teletechman]

Had this set up with a custmer use g.729 for the codec as it is the lowest, also if you are using a laptop no matter how well equipt it will give you problems. I struggled with this for a month just to find out that it is a bad quality at best option from my supplier. Every time the user moved the mouse on the laptop is would cause quality issues, and this was a Dell with 2 gig of ram and 1.8 mobile processor.

 

[kholladay]

You might want to look into using TeleCommuter mode of Phone Manager instead if you can not get acceptable voice quality from VoIP. This way the call control is still maintained by Phone Manager but the voice path is passed over a standard phone line and not subject to quality issues imposed by VoIP.

Kyle Holladay
ACA-I, ACA Call Center, ACS-I, ACS-M, TIA-CTP, MCP/MCTS Exchange 2007
ACE Implement: IP Office

"Thinking is the hardest work there is, which is the probable reason why so few engage in it." - Henry Ford

 

[Mortigan]

I'm going to assume that by 0.25mps you are getting about 250kbps which would only give you about 62KBps on the upload. I'm not nearly as knowledgeable as most of the guys (and girls) on this forum but to me that seems a little low depending on your codec. I would make sure you are using G729 codec to reduce required bandwidth for the call. The ping response time of 40ms is OK but with DSL, and any non dedicated internet connection, you are going to have the possibility of loss and jitter. The consitancy of the data stream on this type of connection is simply not as robust as a dedicated circuit like a T1 or something similar. That is likely where your problem lies.

 

[amriddle01]

You will get much better results with a 4610/5610 VPN phone

ACS - IP Office Implement

"I'm just off to Hartlepool to buy some exploding trousers

 

[mattKnight]

>PC Manager 4.2.12

If by that you mean Phone Manager Softphone...

I'd consider upgrading to the correct version - which is 4.2.22 or 24.

What operating system are you using for teh client?

Have you tried the PMP softphone on the local LAN?

What headset are you using - is it a decent quality one?

250kpbps upload isn't great, but should be adequate for VoIP (G711 requires about 100 -120 kbps) so unless you are hammering the link with other traffic, you should be ok.

Is the QoS scheduler set up on the client?

Take Care

Matt
I have always wished that my computer would be as easy to use as my telephone.
My wish has come true. I no longer know how to use my telephone.

 

[as1981]

All,

Thanks for your help (again!).

Matt:

I'll consider the upgrade. I had 4.2.24 totally destroy all the services on a PC so I am a little wary of it.

Operation system is XP SP2 or SP3

QOS is installed

It's fine on the local lan with the same headset.

Thanks

Andrew

 

[as1981]

All,

Thanks for your help. I've almost got it working. I switched to a different laptop. Maybe the sound card on the first is not good enough to cope.

The sound quality is now perfect but I'm finding that on a second incoming call there is no audio in either direction. I have to close the phone manager, open the sound properties, close the sound properties and then open phone manager again to restore the sound.

This laptop is still using PM 4.2.12 so maybe it just needs upgrading but I thought I'd ask incase either someone has seen this before or I am missing the obvious somewhere.

Thanks again

Andrew