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stds-802-16: RE: QoS Call for Comments
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A reference to voice quality is found in a white paper from Telogy stating
that for voice over packet networks to be sucessful, a quality near that of
the telephone network must be provided. See:
Consideration k) of ITU draft M.1079 agrees by stating "if the quality is
poor and the delay in the speech path is too great, the adoption of IMT-2000
by the general public may not reach the expected level". Since BWA is a
fixed system, it may compete more with fiber and copper service than the
Regarding the QoS Table, three catagories of QoS are listed; Circuit Based,
Variable Packet, and Fixed Lenth Cell.
1. Because the user of a service, for example voice (or conversational)
service, does not care what type network protocol is involved, I do NOT see
a need to specify multiple delay standards based on what kind of network the
service is sent over. Speech is speech to the user. I believe the table
should be media independent based on the service. If we want to have
multiple grades of (real time) service, then why not specify multiple levels
of QoS, still independent of the media.
2. The delay in the QoS table proposed by Arun of 150 ms in packet case and
400 ms in cell case I believe are end-to-end and not what is allocated to
the wireless access portion. The MAC folks need to know what the wireless
access part is, so I suggest that the table reflect only the wireless part.
M.1079 further suggests 20 ms objective for the wireless part in 7.1.4 if I
am reading it correctly. And the media should be independent.