Re: Review of draft-tewg-diff-te-reqts-06.txt

["Thomas Telkamp" <telkamp@gblx.net>]

> >> 3.1, scenario 1, the example of 10,000 uncompressed calls
> >> seems a bit specious. What grounding in reality does
> >> that have? This is supposed to be giving requirements so
> >> it seems the examples should not be merely illustrative.
>
> Some Service Providers are carrying part of their national PSTN traffic
> over their packet network today. Voice VPN traffic is also transported
> over the core. As migration of those continues, 10000 calls is felt as a
> realistic order of magnitude for 1-3 year requirements.
>
> But this text was provided by Thomas from Global Crossing, so Thomas may
> want to add his view.

Indeed, 10000 calls is not a 'specious' number. We currently do more than 1
billion VoIP minutes per month, and around busy sites you will have links
with that amount of traffic (peak).

This example was meant to illustrate that VoIP traffic is not necessarily an
insignificant percentage of the total traffic carried, and therefore
relevant for this draft.

> >> 3.1, second sentence. So I know how to determine the
> >> "certain percentage" of VoIP traffic and it has to
> >> do with a number of factors including the type of
> >> scheduler in the forwarding path. But this sounds like
> >> a lot of handwaving on the part of the authors.
>
> I am not sure what is the specific concern/suggestion.
> Effectively what we're trying to say is:
> - VoIP load can be significant compared to link capacity
> - some SPs feel that controlling the maximum load of VoIP on
> all/some links is one of the tools that will help them control the level
> of QoS [even if this document does not discuss the actual relationship
> between (i) VoIP load, (ii) QoS levels and (iii) other factors including
> type of scheduler]
>
> To be able to address this I'd need to know whether:
> - there is a disagreement that some SPs feel that way
> - we are not phrasing the above clearly enough (specific
> suggestions will help)

The purpose of this draft is not to define such a percentage, but to present
a requirement/solution to maintain a maximum load for this type of traffic.
How this will be used in real networks (what percentage) depends on a lot of
factors that are different for each network, and will be determined by the
SPs.

---
Thomas