VOIP Quality

I am having difficulty getting my VOIP to work well. I have tweaked my system to get good enough audio quality and have read numerous postings herein, however, I still get callers saying they could not reach me...the call is just dumped (meaning, callers are not getting past my router).

Maybe there is a better setup or a differnt router to use though I did try a Linksys router and had the same results.

I have...

VOIP YourLife service
DSL through AT&T/SBC/Yahoo (SpeedStream 4100 PPPoE)
X-Lite softphone (followed Counterpart & YourLife settings)
Vista OS
Core Duo/2 2 GHz CPU
Wireless G connection to router
Netgear WGR614 wireless router
Port forwarding: 5060-5069
SPI firewall turned off

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Scott
Dallas, TX USA

I believe you still need to perform a port fowarding for RTP streams. Perhaps, it is best if you show here your softphone configurations so readers will be able to understand what causes the problem.

My X-Lite settings:

www.pplsuccess.com/data/xlite.pdf

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Scott

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Hi Scott, Are you running Zone Alarm ? Or a similar firewall application, this could be the cause of the problem.

The ports you have opened so far (5060) handle the voice traffic but not the connection setup, there are some more to add. See this post http://www.voipuser.org/forum_topic_322.html

and check through the XLite forum for some further resources, http://support.counterpath.com/viewforu ... 62da9dbfde

The problem could be with Vista if your system does not have lots of memory and real speed and you happen to be using the wrong kind of USB head phones. The machine that I have Vista running on is a bit slower than yours and does not work at all well with Voip. The same machine running Linux and X-Lite-2 works perfectly. Forwarding the RTP ports may help but in the case of my machine the problem rests with Vista and its rather heavy resource demands and I think still imperfect drivers.

Okay, I have forwarded the additional ports in my router and will continue to scour the X-Lite forum for additional answers.

Further on my setup...

RAM- 2 gig
ReadyBoost- 2 gig
X-Lite 3.X
Bluetooth headset

Firewall- I am using Windows Firewall- X-Lite is unblocked. Do I also need to unblock all the ports mentioned, or will they be opened for X-Lite.

I am wondering too, about Vista's resource setup. What about Affinity...should one attempt to play with the cpu cores at all? How about setting priority...I know Vista will auto adjust based on use, but is there any permanent way to force a highest priority to an app (not just right-clicking it in TM)?

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Scott

Hi Scott,

Can you run taskmgr on your Vista to see how much CPU resources it takes for your softphone to operate on a single SIP call?

Just out of curiosity I tried the Windows version of X-Lite 2 on Vista and it seems to run perfectly with good sound. It also set up very easily as it consists of just one executable. I should add that is was running behind 3 routers with newly reinstalled Vista using STUN.

I decided to try something that I should have been done first...make a direct connection from dsl modem to laptop.

Well, no changes...frequent calls are not making it through. I will contact my dsl sp to inquire and post findings herein.

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Scott

It was determined that there was a line outage right at the time I had tried the connection w/o the router...nice timing.

Anyhow, I'm back to the same problem, though I have realized that directly connected via the modem does decrease the latency of the signal.

I have read some posts about the modem I have (SpeedStream 4100) and it is indicated that the modem's NAT and the router's NAT may be a cause. Wondering if one of those 'all-in-one' modem/router would make anu difference.


Here is my present modem config:

www.pplsuccess.com/data/modem.pdf

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Scott

cableghost :

..., though I have realized that directly connected via the modem does decrease the latency of the signal.

Adding a router is the same as adding a hop which usually increase a latency of about 4 msec. If your latency has increased tremendously because of an addition to your router, then there must be something wrong with your router and/or its configuration.

mazilo :

Hi Scott, Can you run taskmgr on your Vista to see how much CPU resources it takes for your softphone to operate on a single SIP call?

Thank you for both replies. I did see that X-Lite does not take a lot of cpu power.

Please see the following for my router settings:

www.pplsuccess.com/data/router.pdf

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Scott

If you are using Vista and X-lite3 then, from my experience, Vista/X-lite3 could be to blame. I tried this combination about a week ago and I was not impressed! That is why I tried Windows Xlite2 on Vista and that seems OK. I was doing this test over a wireless connection (1 router) to a computer router to the input modem/router to the outside world and there was still no significant delay using Linux with X-Lite2. Incorrectly set RTP ports seem to be able to slow down voip transmission. If you have Windows XP then it might be worth trying X-lite3 with that as I understand it works well.

cableghost :

Please see the following for my router settings: www.pplsuccess.com/data/router.pdf

Hi Scott,

I took a look at your router configurations. Since X-Lite does have a support for STUN options, why not use them and remove all the VoIPx ports forwarding on the router? See if this will help.

I guess I am unfamiliar with STUN. I am to assume then, that simply setting STUN in X-Lite will do the same as port forwarding?

I already have the following STUN server set in X-Lite:

STUN.rnktel.com

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Scott