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RE: [EFM] OAM loop back / echo server function


This reminds me how dumb I get sometimes in that I did not jump on this 
I believe that Bob is correct in his statement that looping back Ethernet 
is a really bad idea.

I'll say it again more explicitly:

         Raw physical loopback of Ethernet is a really bad idea.

It breaks/screws up networks that were not designed to tolerate it.

As I have said before, I do believe that we will need a demarcation device 
that has the capability to host OA&M functions.
We have talked about "loop back" from this point in the network.
Let us forevermore make that "PING"


At 12:02 PM 8/30/01 -0700, Denton Gentry wrote:

>>Bob Barrett wrote:
>>Remote loop back of Ethernet packets / 802.3 frames is a really bad idea.
>>No mater how well intentioned it will go wrong sometimes and when it does
>>it is really bad news.
>>I thought we were looking at some form of simple echo server function i.e.
>>take a received packet, swap the SA and DA, then send it back out with a
>>new CRC, same payload ????
>  There was a presentation to that effect at the last meeting, describing
>the merits of the LLC2 TEST frame and how having something like it be
>widely implemented would be a good thing. There will likely be a followup
>presentation in Copenhagen discussing details of the proposed mechanism.
>  I don't think an honest to goodness remote loopback, where the RX is
>logically connected to the TX at the remote end, is even possible in EFM
>for the simple reason that the links we're looking at may be asymmetric.
>PONs and DSL-based copper solutions can provide more bandwidth in one
>direction than another.