Unanswered Question
May 18th, 2009
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i have E1-PRI running on a 2851 voice gateway, the gateway is connected to a port on a core switch, this port belongs to vlan 10.

IP phones are in voice vlan 20

when a call is made from any IP Phone to pstn via this E1-PRI after some time during the call the jitter suddenly begins to rise to a huge values and i can see these values when pressing ? twice on the phone during that call.. the Avg jitter sometimes exceeds 900 !!

at this time the user experiences a bad voice quality and most times the call then is dropped.

i'm trying to investigate why this happens and solve this problem... could any body help me how can i investigate such a jitter problem, could it be Telco problem or since it's a jitter problem means it is something with the IP side of the call not the TDM (Telco side) of the call?

please help me


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paolo bevilacqua Mon, 05/18/2009 - 06:54
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Yes, it means the problem is on the IP side and not telco.

So, you should investigate your local network.


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