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Community Member

VOICE QUALITY If using CIPC from outside to dial PSTN

Hi All,

Voice quality is not good if placing call from Internet using CIPC with vpn tunel and going to PSTN, but its good as long as it is directed within network.

1 ACCEPTED SOLUTION

Accepted Solutions
Silver

Re: VOICE QUALITY If using CIPC from outside to dial PSTN

If you are using Cisco IP Communicator over a remote connection (for example, on a VPN connection from home or a hotel), voice

quality might suffer from insufficient bandwidth. Enabling the ?Optimize for low bandwidth? feature when you are using Cisco IP Communicator over a remote connection can prevent robotic-sounding audio and other problems. To enable this feature, right-click on the Cisco IP Communicator interface and choose Preferences > Audio. You might choose to apply audio filters to enhance voice quality when using low bandwidth.

9 REPLIES
Silver

Re: VOICE QUALITY If using CIPC from outside to dial PSTN

If you are using Cisco IP Communicator over a remote connection (for example, on a VPN connection from home or a hotel), voice

quality might suffer from insufficient bandwidth. Enabling the ?Optimize for low bandwidth? feature when you are using Cisco IP Communicator over a remote connection can prevent robotic-sounding audio and other problems. To enable this feature, right-click on the Cisco IP Communicator interface and choose Preferences > Audio. You might choose to apply audio filters to enhance voice quality when using low bandwidth.

Community Member

Re: VOICE QUALITY If using CIPC from outside to dial PSTN

chked Optmz 4 lwbadwdth, but still the quality is choppy..

further help appreciated

Hall of Fame Super Gold

Re: VOICE QUALITY If using CIPC from outside to dial PSTN

You need to control at least some element in the whole scenario to apply a minimum of QoS. eg, the routers connecting to the internet, etc.

Once you have this, you can describe the details, to see what can be done.

Community Member

Re: VOICE QUALITY If using CIPC from outside to dial PSTN

hi, this is my internet router acl....

access-list 107 permit tcp any any eq www log

access-list 107 permit tcp any any eq 8080

access-list 107 permit udp any any eq domain log

access-list 107 permit tcp any any eq domain

access-list 107 permit tcp any any eq smtp log

access-list 107 permit esp any any log

access-list 107 permit ahp any any log

access-list 107 permit udp any any eq isakmp

access-list 107 deny ip any any log

access-list 108 permit tcp any any established log

access-list 108 permit esp any any log

access-list 108 permit ahp any any log

access-list 108 permit udp any any eq isakmp

access-list 108 deny ip any any log

Please lookinto it

Hall of Fame Super Gold

Re: VOICE QUALITY If using CIPC from outside to dial PSTN

These access list do not control QoS. To answer you question you need to include a diagram for the phone connection end-to-end, indicating which make and model are all the routers / Fws switches , etc that are under your control.

Community Member

Re: VOICE QUALITY If using CIPC from outside to dial PSTN

may be some udp (rtp) is blocked

Hall of Fame Super Gold

Re: VOICE QUALITY If using CIPC from outside to dial PSTN

No, if you have blocked ports you hear no voice, while this is a quality issue. As I said you need to include a diagram explaining your topology. A very simple ascii one will do.

Community Member

Re: VOICE QUALITY If using CIPC from outside to dial PSTN

also below is cfg 4 my pstn gateway dspfarm,,

dspfarm transcoder maximum sessions 4

dspfarm rtp timeout 60

dspfarm codec g729 vad disable

dspfarm connection interval 60

dspfarm

Silver

Re: VOICE QUALITY If using CIPC from outside to dial PSTN

Past experience of problems like this is that the playout buffers on the IP handsets is larger than the default playout buffer on the voice ports of the gateway routers. As a result, calls between IP handsets are fine since they can accomodate the extra delay across the network, but the router voice ports cannot hold the audio segments long enough to wait for delayed packets.

Try the following - depending on the type of voice card you have, configure the 'playout-delay nominal' setting to a higher value (250-500msec) to allow the voice port to wait a longer period for incoming traffic across the IP cloud.

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