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RE: [EFM] Re: OAM Transport Proposal

I thought Packet Engines built a full duplex repeater that was 802.3z
compliant, and that 802.3z had features added to provide this capability.
Now whether the FDR was just a marketing term or what the implementation
really was, is not something I can answer.  Kevin Daines might be able to
answer that better than I. ;)


		-----Original Message-----
		From:	Matt Squire [mailto:mattsquire@xxxxxxx]
		Sent:	Wednesday, April 24, 2002 4:54 PM
		Subject:	RE: [EFM] Re: OAM Transport Proposal

		We've had many threads on repeaters, media converters,
regenerators, and
		the like throughout the evolution of this work.  The
following are my
		recollections as reported by others (Geoff, Tony, etc.).
Pls correct
		anything I misrepresent.  

		1) 802.3 defines half-duplex repeaters.  
		2) 802.3 does not define full-duplex repeaters.
		3) What some people commonly refer to as full duplex
repeaters are
		actually 2-port MAC frame forwarders (802.1D relays?).  
		4) 802.3 does not define optical regenerators (ie protocol
		signal regeneration).
		5) 802.3 does not define media converters.  

		Since using the preamble to carry signaling is intended as a
		function only, I short-cut to the conclusion that preamble
has no
		applicability to any repeater, regenerator, or media
converter as
		defined by 802.3.  Before we could figure out how to address
		full-duplex repeater function that does not exist in 802.3,
it would
		have to be properly defined.  Thats all I was getting at.  

		People are concerned, people are thinking about it, but it
has been
		difficult to address because of the terminology confusion
and our

		- Matt 

		>Hi Matt and all,
		>I will address only the issues related to 5) Regenerators
		>First of all I want to assume that we consider all the
		>including 100 Mbps and GbE. 
		>802,3 defines the above entities. Look at 27. Repeater for
		>Mbps baseband
		>The devices that we address are two port full duplex
		>Also 802.3ab makes extensive references to repeater
		>And again, the moment that we defined any preamble based 
		>capability - see
		>page 9
		>of the baseline presentation - we decided to make the 
		>appropraite changes
		>for preamble
		>I also had some questions, regarding packet based
		>This functionality I assume is not fully contained in the
		>MAC (like the
		>packet based
		>flow control functionality). It requires an external
processing unit
		>(CPU+MAC, HW, or whatever).
		>What is the level of service in the case of a busy link
		>due to a broadcast 
		>storm, etc.)? Do we lose the management capacity for some
		>Wouldn't an out-of-band mechanism (like preamble) be
		>in order to
		>provide even the 
		>basic management information as defined in the suzuki
		>I still think that the compromise should be a functional 
		>compromise, that
		>provide the 
		>best of the two worlds meaning that the capabilities 
		>negotiations should
		>include four 
		>options, and should be done also at the lowest level...