Re: [codec] this weeks summary

["Raymond (Juin-Hwey) Chen" <[e-mail]>]

Hi Christian,

> Raymond did a great job explaining the special requirements of high-density 
> VoIP gateway. They are differ substantially to those of
> soft-phones (but are somewhat similar to VoIP phones with embedded CPUs). The 
> requirements include low memory footprint, ultra-low
> delay, low complexity and mostly narrow band. But aren't those requirements 
> already covered by existing codecs? Shall this working
> group provide a codec profile for end-to-gateway beside the profile for an 
> end-to-end codec?

[Raymond]: Which existing codecs satisfy all these requirements
and the three conditions listed at the beginning of the IETF 
codec WG charter?  Also, we are not talking about an additional codec 
profile for "end-to-gateway"; no, what we are talking about is just part of 
the "IPend-to-transcoding_gateway-to-PSTNend" scenario that you listed in 
one of your original emails that discussed the codec requirements.

> SpiritDSP and Christian were discussing the need for layered coding - no 
> consensus yet...

[Raymond]: I think layered coding (or embedded coding) is a nice feature to 
have.  Some of the other SDOs have standardized layered codecs.  Besides 
the pros and cons of layered coding already discussed last week, I think 
another potential benefit is that as the packets of layer-coded bit-stream 
traverse the network, higher-layer bits can be stripped off by network 
nodes to reduce congestion. (This is probably not done, but can be done.)

> The week before, we were discussing whether to consider Bluetooth and Wireless 
> IP as use cases. It seems to be a rough consensus
> that wireless IP is in-scope and that Bluetooth is out-of-scope because it
> requires too special optimizations. However, battery
> powered, wireless devices might require low-complexity and low-bandwidth (and 
> are in-scope?).

[Raymond]: I read an article that says that PC was the big thing in 
the decade of 1990-2000, Internet was the big thing in the decade of 2000-
2010, and Mobile Internet will be the next big thing in the decade of 2010-
2020. Judging from the recent trends in smart phones, netbooks, and 
Tablets/iPad, it seems that Mobile Internet indeed will be the next big 
thing this decade.  Given this, I think battery-powered wireless Internet-
capable devices should be in-scope, and low codec complexity is an 
important consideration in these devices.