Requested revision
Standard: | 802.1Qaz | Clause: | D2.9.7 |
Clause title: | TC Bandwidth Table |
Rationale for revision
The current text is as follows:
> The table consists of one 8-bit entry per traffic class,
> and always contains 8 entries. Each entry:
> a) Indicates the current TCBandwidth percentage configured for each
> traffic class N where N is 0 to 7.
> b) Total shall equal 100 (implies valid range is 0-100 for each entry).
The problem with the text is that is does not mention
that it is only legal for a bandwidth to be specified
if the TC has been configured for ETS.
Also, in general, if a TLV is determined to be invalid
because it doesn't meet these rules, we should state that
the TLV should be discarded. This text should probably
be added to D2.9.
Proposed text
The table consists of one 8-bit entry per traffic class,
and always contains 8 entries. Each entry:
a) Indicates the current TCBandwidth percentage configured for each
traffic class N where N is 0 to 7. TCBandwidth must be 0 if the
traffic class is not configured for ETS.
b) Total shall equal 100 (implies valid range is 0-100 for each entry).
Impact on existing networks
Existing implementations could be doing one of two things
- Discarding the TLV because it is invalid (which would
be the correct behavior), or
- Ignoring the fact that the bandwidth has been specified
for a non-ETS TC, and simply using the percentages for
the ETS classes as relative weights.
Making this modification would just force everyone to
use the implement the first option.
Originator
Name: | Anoop Ghanwani | Email: | anoop@alumni.duke.edu |
Affiliation: | Dell | ||
Submitted: | 2012-01-06 |