Reply to MEF 27028-002 (from MEF NID group)

The IEEE 802.1 Interworking Task Group thanks the MEF for the liaison, and encourages 802.1 members to continue to contribute to the work of the MEF.

The Flow Metering function in 802.1Q and 802.1ag meters frames by
input port, not output port, as stated by the first sentence of
IEEE 802.1Q-2005 Clause 8.6.5.  The position Flow Metering, near
the end of the Frame Forwarding chain (clause 8.6, Figure 8-9)
means that it meters only those input frames that are actually
queued for transmission on at least one output port.

The 802.1 IWTG understands that both input and output flow metering
are useful, and regrets that 802.1Q Figure 8-9, and 802.1ag Figures
22-2 and 22-4 can confuse the reader as to whether metering is
applied on input or output ports.  These issues can be addressed
when 802.1Q is next revised.

The issues raised by your liaison on P802.1aj Draft 3.1 have been
processed as a ballot comment on Draft 3.1 at the IEEE 802 plenary
meeting in Dallas, Texas, this week.  The disposition of this
comment is that the next draft of P802.1aj, Draft 3.2, will include
an explanation of the relationship between the MAC Status shim and
Maintenance Point shims, along with one or more figures to clarify
the positions of Maintenance Points and the MAC Status shim in a
Two Port MAC Relay.

Thank you for pointing out these two issues.