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Ip Set Codecs

Ip Set Codecs

Ip Set Codecs

I'm having issues with BCM450 and bad audio which seems to vary from time to time. It seems to run fine at times for days and others for hours. In an effort to minimize these problems, I've been trying to adjust the codecs. Can these be adjusted on the fly or does it require a set or system reboot? I've made changes and they don't seem to be reflected. Also by selecting Auto in either the IP terminal global settings or the individual IP sets, is there some optimum setting that would allow for codec change on the fly that would actually change according to conditions?

RE: Ip Set Codecs

Seems like you are sure it is the BCM 450 codec, before you focus on the codec, have you verified

1. No internal cabling issues (from handset cord to the patch panel)
2. The external phone lines from the Telco are tested clean by the carrier, particularly with PRI lines.

RE: Ip Set Codecs

you ask for codec, it is IP sets with TDM trunks or IP sets with SIP trunks? Or digital and IP sets with SIP trunks?
what is your configuration? can you give more details?


RE: Ip Set Codecs

Hello all!

It's a BCM with a PRI and the IP sets are remote off site using the public IP to access the BCM via the NAT Transversal licence. I'm wondering if it would be better to set up a VPN to the remote site to optimize the connection? I was asking what the setup would typically be for getting the BCM to pick the optimum codec automatically if possible based on provisioning, (if that's possible). Considering there's an auto function, does it actually change codecs based on condition. I know played yesterday with changing codecs both in the general settings as well as set specific and wasn't sure if I was getting a change. On Monitor, when the set specific was changed it showed the new codec but on default or general settings changes did not reflect until possibly re-boot.

RE: Ip Set Codecs

If the IP phones are offsite I would guess you are having latency/jitter issues or lost packets at some point. Either the local or remote side.

VOIP doesn't need much bandwidth but it suffers greatly from inconsistency in packet delivery. QoS is often used to help solve this so that voip packets do not get buffered or dropped when a big download or upload is hogging all the time on the connection. A small reduction in voip bandwidth by changing the codec isn't likely to do much good and can even make the problem worse as losing a single packet of a more efficient codec will result in a greater amount of disruption to the voice quality. You have to solve the actual cause of the problem which is likely the fact that any high demand on your connection is delaying or dropping voice packets.

A VPN might help but would do nothing if you do not have measures in place to prioritize your voip traffic over regular use.

RE: Ip Set Codecs

Check on the IP phones there is a menu with network statistics. So will you see how many packets are lost etc.
It is a free build in tool to measure quality.


RE: Ip Set Codecs

Interesting! I'll take a look if you say it's on the IP phones specifically. I did find with an IT guy that he ran a program that identifies Packet Loss. Interestingly, it shows like a tracert and shows each step in the process with a graph and identifies which section of the route is losing packets with a percentage loss. I found that after it got handed off to a particular company stateside on route to overseas, there were packet loss both on the acceptance, internal switch handoffs and again on the final pass off to the next carrier that amounted to 20% packet loss. The one thing that I'd like to know is I've been fighting not only this problem of packet loss which has tended to vary on the BCM monitor showing 1 or 2 % packet lose up to 15%, but I'm more interested in knowing if anyone has had a major packet loss problem as it seems to be causing the BCM to lock up with a series of alarms starting with "Media Path Server has stopped unexpectedly". This causes a whole series of alarms that shut down services requiring either a manual reboot of the system or it does come back up on its own after a varied time interval from 5 minutes to more. Sometimes I'm told it even locks up the digital sets in the office preventing them from taking calls? It's almost like the BCM says "OK, I've had enough of these errors, I'm shutting down and rebooting to see if I can clear these problems". This has been ongoing with first a BCM50, then 2 different BCM450s. Anyone gone down the same road as unusual as it seems.

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