sundance-communications.com/forum Forums VOIP Phones & IP PBX VoIP & Cloud Phones, Hosted PBX, General IP Phones ip pbx

I have installed a new ip pbx on our network, and all seems ok, however from time to time there are network issues that i need to fix quickly. Can anyone recommend a network monitor that is geared towards monitoring and testing all the connections on my network. I have tried some programs that i have found on the internet however none of them really help. Any suggestions would be helpful.

That is a very ambiguous question. What type of IP PBX? How many phones? Do you have one wire running to the desktop or two? Doe you use POE or local power on the phones, what type of IP phone are you using? Are you haveing issues with local IP phones or remote IP phones, or both?

Steve

And what type of switches are in your network?

the system is a new ip pbx introduced august last year WIN eNet200. 35 phones and it is a mix of one, and 2 cat5e connections per workstation. the remote ip phones work good, however the problem seems to occur when there is a conversation between 2 or more internal extensions in house. there is alot of echo when the volume is turned up on speakerphone. the manufacture insists it is a full duplex speakerphone, however i would like to see the network performance before pursuing upgrading switches and running new cable for each phone.

if the problem is in the switch or if it is a cable problem, and suggestion would help.

the switches are supplied by manufacture and they supporm vlans and qos however we have not utilized these features yet. suggestions would help.

has anyone else had speakerphone issues out there in a pure voip system?

Speakerphone echoes when the volume is turned up? Sounds like plain old-fashioned cheap-speakerphone syndrome to me. Only answer is to buy a better quality speakerphone, turn down the volume, or hang things on the walls to minimize hard surfaces.

To test this, just put a bedroom comforter over your head as you use the speakerphone. Does the echo go away?

If the chassis of the phone doesn't insulate the speaker from the mic well enough then turning the speaker phone up will result in echo and feedback. There may also be issues regarding the firmware used on the phone to do echo cancellation. Echo cancellation works by looking for a similar sound pattern on the incoming (mic) line as what was just sent out on the outgoing (speaker) line over a certain time frame (G168 is 128ms I believe). If the firmware is not tuned properly to the speakerphone chassis and mic pickup patterns then you will run into the problem you are having. This can be tested by taking a sound dampening material, like a comforter, and draping it over the microphone and seeing if you have echo still.

If the room has a tendency to echo then this will be very hard to tune out. The sound is usually fairly well distorted by the time it gets back to the phone and the echo-can doesn't recognize it. Also, the more ambient noise you have (sound floor), the harder it will be for the phone to correctly do echocan.

BTW, if your speakerphones were not full-duplex then you wouldn't have so many echo issues. Half-Duplex is more forgiving to noisy environments and places with bad echo, at the expense of being able to talk and listen at the same time.

At any point are these phones crossing technology, meaning that there is a PSTN line in this conversation somewhere? What was once sidetone on TDM is now echo in SIP. If the switch doesn't correctly compensate for this you will get echo. Pumping out too much gain on the TDM side will also result in echo on the SIP side.

If you feel comfortable, you might open up the phone and put some foam rubber around the speaker and mike to minimize acoustic echoes inside the phone. You might also insulate the speaker from the chassis using some small faucet washers or O rings.

thank you i will try these suggestions and report back later this week.

Ans interesting subject. We're assuming these phones have separate mics and speakers. I'm pretty sure my phones (Avaya) use the same transducer to do both functions. That is, the speaker is also the microphone. Full duplex. Never had an echo problem.

I am intrigued by the thought of people having an Afghan close by for speaker phone calls. Can you see three for four of them under the blanket on a conference call? "So, what do you think of our proposal Mr Smith?" person two mutters "Hurry up, it's getting hot in here". Person three rolls their eyes. Mr Smith responds. "Price seems a little high". ... Person four whispers "Just lower the price so we can get out from this darn blanket. The battery on my flashlight is dying".

The thought is funny, but you can usually just use a clean rag or work shirt or paper towel, as long as it will muffle the sound.