[RTW] WG charter, take 4

[Magnus Westerlund]

Hi,

Sorry for not having produced these charter comments earlier as most
would apply to earlier versions also. However, I do have a number of
comments on it and think the charter could be restructured to become a
much better charter. But lets start with the different comments.

The most fundamental issue with the charter is that it contains to much
technical solution candidates, rather than talking about the goals and
and general direction for achieving them. I think one needs to extract
the few higher level goals from this list and work them into the charter
in other ways. Certain things we likely can select, like RTP. But there
is clearly a question on what profile and extensions that should be
supported.

I also think one of the biggest uncertainties and fuzziness in the
charter is because the model isn't agreed on. The discussion about the
session management is clear due to that the model for the work aren't
agreed on. I see two ways here. Either we manage to lock down the model
prior to the chartering, or we have a charter that included this model
discussion. Frankly I see the later as most likely as agreement on the
model will require agreement with IETF's partner in this work. Thus the
charter should take a bit more height for having such model discussion.

It is already obvious that any codec selection for this is going to be a
difficult and possibly take time. To avoid this from de-railing the
truly fundamental parts of the RTC-WEB solution, I am suggesting that
this should be taken in its own WG, or if not possible at least as a
separate WG item, with its own deadlines, so that it doesn't hold up
the main work. That is likely anyway a good idea for long term purpose,
so that only the codec selection part can be updated, and not the
fundamental part when the set of codecs become out-dated.

I still don't understand the diffserv based QoS. This seems very
unrealistic to be usable from a web-browser perspective. This as no
device in any setting other than being an ISP controlled device is
likely to be allowed to set DSCP. I think QoS can be excluded at this
stage completely. Especially as there are a lack of methods for
providing end-point devices with a traffic class to DSCP mapping valid
in the currently attached network.

The charter could also be clearer on the need for basic datagram and
byte stream functionality between two peers. The higher motivation for
it is there, but not requirements. Where I see rate control and
security of those channels being the most important ones.

I am also missing a clear requirement for enabling future extensions of
functionality of the RTC-WEB components in the browser. I see this as
important as we can hopefully arrive at the basic functionality
reasonably quick, but there will be certain set of functionalities that
are desirable but not quickly arrived agreed upon and specified. We need
a method for enabling introduction of these in the future.

I also think one can clarify the last deliverable to actually be
requirements on signaling and the API. Different functionalities will
have different requirements when it comes to data objects needing
exchange and also how the negotiation between the peers happens.

I am also missing a clearer requirement in ensuring that this becomes a
network friendly traffic source. There is clearly need for congestion
control and media adaptation as part of the basic solution.

As have been raised security is an important part of this work. I think
we need to ensure that the WG first establish a security model, and then
follows it in development. I fully agree that there should be no
separate documents, this should be part of the general architecture, as
it is such a fundamental part.

I am willing to provide an alternative charter proposal, if there is
interest, attempting to take these comments into consideration.

Cheers

Magnus Westerlund

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