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CORRECTION Re: [EFM] EFM Requirements


At 08:09 PM 8/20/01 -0400, Matt Squire wrote:

Harry Hvostov wrote:
> Matt,
> For the record, the actual stream transport for VoIP is done via RTP/RTCP -
> application
> layer protocols. Needless to say, these protocols would rely on the QoS
> mechanisms supported at L2/L3. For an example of mapping the MGCP session
> descriptions into L2 QoS parameter
> sets please see PacketCable 1.0 Dynamic QoS specification at
> The spec is publicly available.

So what.  At the Ethernet level a packet has priority.

For the record: At the Ethernet level, a packet has NO priority.

There is no mechanism to manipulate or order Priorities anywhere in 802.3
There is a field allocated in the 802.1Q VLAN TAG that allows "user priority" information to be transported across Ethernet in an agreed upon location within a packet within a particular Ethernet protocol (802.1QTagType: 0x81-00)

This information location of not normative in 802.3
This information acted upon anywhere in 802.3

This priority information is a feature of 802.1Q, not 802.3
There are many other Ethernet protocols,each with their own identifying Type number. More than a few of them have a field for priority information. We (802.3) treat those protocols in exactly the same way that we treat packets of the 802.1Q protocol type, that is, we send them and receive them between the MAC Client and the medium on a first-in, first-out basis. That's all.