[asterisk-dev] clearmode again (RFC 4040)

[Tilghman Lesher]

On Tuesday 25 May 2010 09:29:04 Klaus Darilion wrote:
> Some time ago we had lots of discussion about adding a clearmode
> "pseudo-codec" to Asterisk.
>
> As (citation from RFC 4040)
>
>  >    "Clearmode" is a basic feature of VoIP Media Gateways.
>
> I wonder if now the time has come for Asterisk to be open for such an
> feature?

I don't think we're necessarily opposed.  The issue is that I'm not sure how
useful such a provision would necessarily be.  While I'm clear about the
usecase, I'm not clear about the practicality of such.  The RFC specifically
says that it makes no provision for the problem of lost packets, and on that
count, it falls short.  ISDN circuits are provisioned with the possibility of
data corruption, but not with the possibility of losing 800 frames (10ms) all
at once.

It's much better to standardize how to correctly interpret a conversation on
the ISDN level, packetize the message and establish a mechanism to ensuring
that all packets arrive, then reassemble the digital signal on the other end,
much the way T.38 works.

Do you have a real need for this, or is this just a whiz-bang feature?

-- 
Tilghman Lesher
Digium, Inc. | Senior Software Developer
twitter: Corydon76 | IRC: Corydon76-dig (Freenode)
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