MeetMe --- g729 got a bad quality

[3dtgnt_ljm]

Hi  All,

we have a center cucm 5.1.3 and a remote site , between HQ and Remote using G729, my question is :

when I create a meetme in HQ (using SW CFB), if Remote iphone join it , they will get a very bad quality, at that time , I show dspfam all in HQ voice gateway , I can see the XCODE working . how can I do ? I won't change back to G711.

[Chris Deren]

Is your question how do you ensure the call is setup as G711?

If so, you need to define a new Region that is set to use G711 between all other regions, build new Device Pool that uses this Region and assign this DP to the conference bridge (CM server). 

Keep in mind though that this will force all conference participants to negotiate G711 codec which means you need to ensure your bandwidth to/from remote location is adequate, your Call Admission Control may need to be tweaked as well depending on what you have configured.

HTH,

Chris

[3dtgnt_ljm]

Hi Chris,

I made sereval DPs and Regions, and I am sure HQ and remote using G729, if the call between HQ and remote phones, the quality is better. only meetme is not good . HQ and remote have a 2M lease line and I reserve 512K bandwidth for voice .

[yahsiel2004]

How are MeetMe calls with a phone in HQ and a customer outside of the network? Are the MeetMe calls between the HQ and the Remote site made during peak times? I would try making a MeetMe conference after hours between the HQ and the Remote site to verify that the issue is not bandwidth related.

Regards,

Yosh

[3dtgnt_ljm]

Hi Yahseil2004,

HQ phones and outside call meetme have very good quality, only remote site not . I think it should be the XCODE or CUCM have unsuitble settings.

[yahsiel2004]

I have 2 options I would try before blaming the XCODE.

Option 1:

Make a test MeetMe conference during after hours and or non-peak times. To verify that this issue is not bandwidth related.

Option 2:

You can change the Media Resource Group to use the Hardware XCODE first so that you can start a local MeetMe using the Hardware XCODE and veirfy that the issue is not the Hardware XCODE. If the call sounds good I wouldn't completely ignore the XCODE as being the issue since this test call wouldn't be in G729; so that being said if you want to make a good test call you would have to create a dummy region (or use the remote region) and assign it to a test phone starting the MeetMe conference.

If the issue still presist I woud open a TAC case to verify if the DSPs need to be replaced and or to perform further troubleshooting.

Regards,

Yosh

[3dtgnt_ljm]

Hi Yosh,

Thank you again.

option1 : I am sure it is not bandwidth related.

option2 : if I use HQ hardward conference , meetme work well. but in HQ conference always have more than 8 parts. so I have to use software resource , I know DSP conference only support up to 8 parts.

[yahsiel2004]

Dspfarms supports more than 8 calls per session depending on the size of the DSP, the codec types and how many sessions is configured under the dspfarm.

Have you gotten any further with this issue?

Regards,

Yosh

[3dtgnt_ljm]

Hi Yosh,

I really puzzle about DSP and your viewpoint. PVDM2 can support more conference but up to 8 parts per conference.

I changed HQ and remote codec back to G711 eventhough take more bandwidth.

[paolo bevilacqua]

Yes G.711 takes more bandwidth, but that is cheap these days.

But G.729 almost invariably gives troubles and complications.

That is why it's better to avoid if possible at all.

[yahsiel2004]

I'm not sure what you mean by 8 parts I am assuming you mean 8 calls per sessions. What I was trying to say was that depending on the type of codec you have configured under your dspfarm for conferencing will determine the amount of sessions allowed and the calls per sessions as seen in the examples below.

I'm using 2 PVDM2-64 for this example

g711 will allow a maximum of 16 sessions with 32 calls per session.

dspfarm profile 100 conference

codec g711ulaw

codec g711alaw

maximum conference-participants 32

maximum sessions 16

associate application SCCP

g711 will allow a maximum of 64 sessions with 8 calls per session.

dspfarm profile 100 conference

codec g711ulaw

codec g711alaw

maximum sessions 64

associate application SCCP

Because we have g729 configured we can only have a maximum of 16 sessions with 8 calls per session.

dspfarm profile 100 conference

codec g711ulaw

codec g711alaw

codec g729ar8

codec g729abr8

codec g729r8

codec g729br8

maximum sessions 16

associate application SCCP

I hope I clarified my viewpoint better.

Regards,

Yosh

[3dtgnt_ljm]

Hi Yosh,

you are right . I never know DSP can support more than 8 parts before, you let me learn more , thank you !

sccp ccm group 101

bind interface Loopback0

associate ccm 1 priority 1

associate profile 1 register XiAn-conference

keepalive retries 5

!

dspfarm profile 1 conference 

codec g711ulaw

codec g711alaw

maximum conference-participants 32

maximum sessions 2

associate application SCCP

-----------------------------------------------------------

G729 can support up to 16 not 8

dspfarm profile 1 conference 
codec g711ulaw
codec g711alaw
codec g729ar8
codec g729abr8
codec g729r8
codec g729br8
maximum conference-participants 16
maximum sessions 1
associate application SCCP

[yahsiel2004]

Glad I could help.

Regards,

Yosh