Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

RE: Chapter 46: preamble length


Yes, I would disagree with that.  I agree with what Pat said about MAC
transmitter being required to send the full preamble, but the MAC receiver
being tolerant to preamble shrinkage.  I remember that Gigabit Ethernet MAC
receivers that were designed for only 8 bytes of preamble, even though the
standard permitted 7, had some interoperability problems with systems that
occasionally generated 7 bytes of preamble.  Thankfully, the UNH IOL caught
these issues in a non-biased manner.

As for where in the draft, I don't think there is any text that directly
tells you how to do preamble shrinkage. There is text that describes the
occurrence of preamble shrinkage (hence this thread).  Another question
would be: is there any text in the draft that strictly forbids preamble


		-----Original Message-----
		From:	Ben Brown [mailto:bbrown@xxxxxxxx]
		Sent:	Wednesday, March 28, 2001 10:44 PM
		To:	stds-802-3-hssg@xxxxxxxx
		Subject:	Re: Chapter 46: preamble length


		In my opinion, after reading the drafts, I would say that an
		implementation which chose to change the length of the
		for any reason, would be non compliant. I think you would
		disagree with this statement. I wonder how many others would
		disagree with it. Also, where in the draft does it allow an
		implementation to change the length of the preamble?