Jamal,
let's list the features need to be provided for 802.11 QoS, and problems.
It is worth to provide standard interface with wireless stack; otherwise each
driver will invent its own solution.
1. NIC have number of Tx DMA channels, with different channels used for
different priorities. It is dictated by standard (TGe).
Most likely, it should be 4 queues for EDCA traffic (4 priorities), 1 for HCCA
(polled, pre-agreed streams) and optionally 1 for multicast traffic (AP need
it).
Each queue need to start/stop separately. For flexibility, it should be some
way for driver to request queues and specify mapping to these queues.
Ideas for how to implement it in stack?
Meanwhile, ideas how to get separate per-priority control with existing
infrastructure?
2. There is traffic that require admission control. Unless driver performs
allocation with AP, this traffic is not allowed. TGe standard dictates it.
Driver should participate in bandwidth allocation (via RSVP?). It should get
some form of request (IOCTL?) which it will serve by performing allocation on
link layer. It is easy to do proprietary IOCTL and white custom RSVP daemon,
but it is much better to do something generic for all drivers to use.
Vladimir.
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