Re: [EFM] EFM Requirements
Talking about voice transport...
At 20:09 20/08/01 -0400, Matt Squire wrote:
>So what. At the Ethernet level a packet has priority. Someone has
>classified this packet as important. Therefore, the network should do
>what it can to not discard the packet and to give it a relatively low
>latency. The packet can be carrying voice, video, or my mother's secret
>lasagna recipe - I don't care. I've been told its important - the
>application is irrelevant.
I must make sure that we are talking about the same Ethernet here. Ethernet
by itself has no priority mechanism. A bunch of proprietary schemes were
created, and some standard work was done, but I'm not aware of any widely
deployed, complete, standards-based, solution for prioritization on the
Ethernet level. I'm happy to be proved wrong, though, as it would be
something really nice to have.
Now, if EFM will have the mechanisms to tag packets as important
(non-discardable, low latency, and so on), then you're right. You are
simply mapping IP QoS over Ethernet. But even then, the standard group has
some work to do, to make sure that the prioritization mapping is done the
>The point is that the Ethernet layer has no additional work to do to
>carry voice. Therefore the requirements for transporting voice need not
>be singled out - there are none.
As I said, this is not granted - at least as far as I know. You have
pointed out that there are several ways to carry voice; in my opinion, some
of them will need specific provisions in the standard. If we can map
everything to standard features of the Ethernet, then you're right, and we
have nothing to worry.