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RE: [EFM] Re: OAM Transport Proposal

I assume that you are right regarding the definition of the full-duplex
There is no such definition in the 802.3 standards.
Practically there are two types of repeaters - as you mentioned:
1. A full duplex repeater - as per the 802.3 definition w/o the half duplex
   Generally this is implemented by two PHYs back to back with some MII data
2. What you defined: a switch with/without the learning function disabled.
   two MACs back to back.

I totally agree that we should better define the requirement. But this is a
reality that 
exists in huge numbers and as per service providers that use this solutions
management capability is required. 

Now my main point is that with an auto-negotiation mechanism that will
contain the capability 
of only preamble. This will support whatevere definition we can provide for
the repeaters.
Then everythig is already there !!


>>-----Original Message-----
>>From: Matt Squire [mailto:mattsquire@xxxxxxx]
>>Sent: Wednesday, April 24, 2002 2:54 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 agnostic
>>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 this
>>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 and 
>>>First of all I want to assume that we consider all the 802.3 
>>>including 100 Mbps and GbE. 
>>>802,3 defines the above entities. Look at 27. Repeater for 100 
>>>Mbps baseband
>>>The devices that we address are two port full duplex repeaters. 
>>>Also 802.3ab makes extensive references to repeater implementations. 
>>>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 functionality. 
>>>This functionality I assume is not fully contained in the new 
>>>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 (even 
>>>due to a broadcast 
>>>storm, etc.)? Do we lose the management capacity for some time?
>>>Wouldn't an out-of-band mechanism (like preamble) be valuable 
>>>in order to
>>>provide even the 
>>>basic management information as defined in the suzuki proposal?
>>>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...

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