HELP ip phones cutting out

[telcorookie]

I have a IP 500 with 4610sw, our connection is a product called a ILAN which the telco provider is providing 1.5 t-1 to each location and connects them together. If i do a speed test on the internet i get good speeds. But for some reason the phones keep cutting in and out like if your were on a cell phone with bad reception. I have installed a QoS router and that didn't seem to help at all. The problem is not consistant, but it does happen quite often. Any suggestions on how to correct this?

Thanks in advance...

 

[amriddle01]

What Qos did you set up with the router? What are your call stats like in SSA (jitter, packet loss etc)?

ACS - IP Office Implement

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

 

[mattKnight]

>I have a IP 500 with 4610sw

You need to tell us how this laid out. At the moment we are guessing.

It could be that your internet connection won't support voice communication, but that would only affect remote phones. Are these phones remote.

If they are on the LAN, are they on a separate VLAN etc



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.

 

[mattKnight]

Did you carry out the Network Assessment?

What does your BP say?



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.

 

[telcorookie]

The ILAN product is setup where 1 office is the Main office. and other offices are remote.. Main office has a PRI with a full T-1. Remote offices connect through a t-1 circuit to main office through this ILAN product. So main office has to supply voice and data to remote locations. We did install a rsv 4000 qos router, which has not really helped that i noticed. My next step was to put them on a vlan which i am a noob on. I was told a vlan would not make a difference, but i am unsure of the correct answer to that. Like i said, if i do a speed test at the remote locations i get a 1.5 up and down. if i look at the phone applications, there is no packet loss or anything that i can see.

Regards,

 

[teletechman]

Do you have the phones and system set to auto for codec if so change to G729, also it sounds as thou you are going thru the internet and not an MPLS or point to point for the SCN if this is the case then you have no QOS. The only thing you could do is set up outbound QOS to try and manage the best you can.
Mike

 

[mattKnight]

> I was told a vlan would not make a difference

Probably not in this case.

What codec are you using. Id suggest you use G729 (certainly rather than auto negotiate) and probably instead of G711 (G711 uses >2 tine bandwidth)

How is your Qos set up (are you sure that the Qos is end to end) and matches the setup of the IP office

If you look on the knowledge base there is a worked example of how to check that the QoS is being tagged correctly.



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.

 

[HairySupportMonkey]

QoS will do bugger all as well, as the QoS packets also need to be recoginsed by your ISP.

can you get your ISP to prioritize H323 packets?

what does a trace route look like from the HO to the remote site? any black holes / flapping routers?

ensure you also turn off any inspection maps (cisco speak) on your H323 proxies / firewalls.

trouble is unless your ISP can offer some sort of traffic priorities for your voice data, then once it hits the internet all the QoS tagging in the world wont help.

Id say your packets are being fragmented and being sent all over the place.