How to select Codecs?

Discussion in 'General' started by leiw3248, Dec 24, 2009.

  1. leiw3248

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    Hello

    I read Elastix-without-tear already (p.38), used command "core show codecs" to show all codecs, how to select prior for those codecs ?
     
  2. Patrick_elx

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    your codec selection is in the config of each trunk/extension.

    ie: disallow=all
    allow=gsm & g729


    For each comm, each side is telling the other which codec is allowed, and will chose the first common one.

    You can have many codecs available on your server, but want to limit the choice on some trunks for different reasons:

    - bandwidth limitation: use a compressed codec (gsm, g729, ...)
    - quality optimization (fax for instance) g711
     
  3. leiw3248

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  4. rafael

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  5. leiw3248

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    Hello

    Thank for your information, could you give me some codecs experience how to setup 100Mbps local lan network, we have 13 IP-phone / Intel 4700 CPU with 2GB / Elastix 2.6.0 / 50 users / only for local lan, no another site.

    Now, I setup extensions and IP-phone with u-law, I think 100Mbps local lan network can handle it.

    As my setup, extensions and IP-phone are same u-law, will Elastix use more CPU resources for decompress ?

    Thank !
     
  6. leiw3248

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    Hello

    You mean I can config codecs in extension? I can't see that.

    Thanks !
     
  7. Patrick_elx

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    Look in your extensions tab in the gui,

    you have two lines:
    disallow
    allow

    you can also set it for all sip channels in your sip_general_custom.conf
     
  8. leiw3248

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    Hello

    Thank for your information, could you give me some codecs experience how to setup an 100Mbps local lan network, we have 13 IP-phone, the Elastix 2.6.0 server has Intel 4700 CPU with 2GB, we have 50 users but not concurrently call, we don't have another site only for local lan.

    Now, I setup extensions and IP-phone with u-law, I think an 100Mbps local lan network can handle it.

    As my setup, extensions and IP-phone are same u-law, will Elastix use more CPU resources for decompress ?

    Thank !
     
  9. Patrick_elx

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    Asterisk will use some cpu to transcode a codec to another one.
    If your trunk is in ulaw and your extensions are in ulaw, there is no transcoding involved then no additional cpu load.
     
  10. leiw3248

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