We are using Distro Free PBX version 2.9.09. We have hosted this PBX system on a reasonably fast server i.e Dell power edge 1950 host on a collocation site with dedicated 10Mbps connection burstable to 100mpbs. Objective was to sell VoIP Phone package to home and business users like VoIP companies such a Vonage and commwave.
For over a year we slowly increase our client base from 50 extensions to 170 extensions. From last 2 months we started experiencing voice quality issues. We are experiencing Jittering and crackly voice at random times.
From the research we did on the forums, the most possible cause given for jittering voice could be the bandwidth. We monitored the bandwidth and our peak usage at a given time was lower than 3mpbs, our dedicated bandwidth was much higher than that.
We tried to troubleshoot with the collocation support team they did some fine tuning bit were unable to help us further.
We then sourced another Collation provider and moved our PBX server to the new site but the Jittering is still there.
Other observation is that during business hours (peak hours) the jittering is much more and off-peak hours its much less.
This makes me feel, is this load related? Our system statistics range is as follows:
Load Average: 0.41
Typicaly: CPU:1% - 26%
eth0 receive 65.31 KB/s - 150 KB/s
eth0 transmit 66.55 KB/s - 150 KB/s
Our Hardware overall I see the system is used at 10-20% on average.
And FreePBX Statistics range is typically as follows:
Total active calls: 2 - 25
Internal calls: 2 - 25
External calls: 2 - 25
Total active channels: 6 - 50
IP Phones Online: 168
IP Trunks Online: 11
Two Month ago when we probable has 100 minus extension we never experience jitteriness.
Q1: What I want to know how scalable is free pbx. What is the loads level it can typically handle? Can this platform be used to become a phone service provide over WAN link to approximately 1000+ extensions with 25% concurrent live calls? Or it is designed for small medium size companies to handle 25-50 extension over a LAN link?
Q2: From the scenario explained above what could be the most probable case of jittering
Experience advise is desperately needed.