Re: Specifying audio codec on fixed termination

Hello Francois,

You can use the attributes from H.248.1 Annex C. i.e ACodec from C.1 or 
layer1prot from C.9. If you want to carry these in the text encoding use 
H.248.15 and a package ID of "anxc" (as defined in  Annex C).

Regards, Christian

Tom Taylor wrote:
> Once upon a time (almost ten years ago) I created an SDP solution for 
> ISDN, but eventually backed off before it was standardized. I forgot 
> about the need to specify a transport for the media in the m= line 
> when I answered you today. Either we would have to carry the necessary 
> changes through as a new AVT profile or you'll have to use some sort 
> of trick.
>
> François Plagnard wrote:
>> Thank you for your answer.
>> But, now my concern is how to specify an audio codec in a B channel 
>> in Local descriptor?
>> I have found no way to describe it in SDP format contained in Local 
>> descriptor (there is no RTP involved here or any other transport).
>>
>> Best regards,
>>  
>> François Plagnard
>>  
>> -----Message d'origine-----
>> De : Tom Taylor [mailto:[email protected]] Envoyé : vendredi 4 
>> décembre 2009 17:23
>> À : François Plagnard
>> Cc : [email protected]
>> Objet : Re: [Megaco] Specifying audio codec on fixed termination
>>
>> It is legitimate to specify a Local Descriptor for the B channel 
>> termination, indicating which codec is being used.
>>
>> François Plagnard wrote:
>>> Hello,
>>>
>>>  
>>>
>>> In a gateway between ISDN and IP, B channels on ISDN side are fixed 
>>> terminations.
>>>
>>> In some ISDN networks, the audio codec used line may vary per call 
>>> (often between G.711 A law and mu law).
>>>
>>> How this audio codec may be indicated by the MGC to the gateway?
>>>
>>>  
>>>
>>> Best regards,
>>>
>>>  
>>>
>>> François Plagnard
>>>
>>>  
>>>
>>>
>>>
>>>
>>> ------------------------------------------------------------------------ 
>>>
>>>
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>>
>>
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