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RE: Ideally BER should be a customer controlled option




Ed:

Please don't get me wrong.  I think a standard should be set for BER, so
that at least to insure compatibility and interoperability.  I also know
that a flexible BER may be a pipe dream.  The factors that influence BER
tend to very non-linear and as such a flexible BER may be very difficult to
implement in practice.  However, I would be interested to see if any
manufacturers would provide a knob for BER, or at least provide a spec sheet
outlining the various factors that may effect BER and what steps could be
taken to push the BER envelope beyond the agreed upon standard if so
desired.

Bill

-------------------------------------------
Bill St Arnaud
Director Network Projects
CANARIE
bill.st.arnaud@xxxxxxxxxx
http://tweetie.canarie.ca/~bstarn

 

 



> -----Original Message-----
> From: Chang, Edward S [mailto:Edward.Chang@xxxxxxxxxx]
> Sent: Tuesday, June 01, 1999 4:42 PM
> To: bill.st.arnaud@xxxxxxxxxx; Rich Seifert; Jaime Kardontchik; Chang,
> Edward S; stds-802-3-hssg@xxxxxxxxxxxxxxxxxx
> Subject: RE: Ideally BER should be a customer controlled option
>
>
> Bill:
>
> It seems you picked one unpopular suggestion, so far, no one
> seems to agree
> with you yet.
>
> Sorry, my friend, I am also not quite ready for a flexible BER.
>
> In addition to the comments from others which I agree, if we let BER be
> flexible, we will have incompatibility equipment all over, and we may need
> something similar to auto-negotiation to find the BER
> (reliability) of other
> terminals before transferring data.  I do not think we need that extra
> trouble.  So far the BER works fine for us to set the minimum reliability
> for data transfer, and COST-EFFECTIVE.
>
> Ed Chang
>
>
>
> -----Original Message-----
> From: Bill St. Arnaud [mailto:bill.st.arnaud@xxxxxxxxxx]
> Sent: Sunday, May 30, 1999 8:30 PM
> To: Rich Seifert; Jaime Kardontchik; Chang, Edward S;
> stds-802-3-hssg@xxxxxxxxxxxxxxxxxx
> Subject: Ideally BER should be a customer controlled option
>
>
>
> All:
>
> Realizing that there are some practical limitations, as much as possible,
> BER should be a customer controlled option.
>
> If I am running only IP with high number of a TCP transmissions I may
> deliberately want a high BER to act as layer 1 WRED.  Also I may
> be able to
> push my repeater distance using low cost laser and a willing to suffer a
> higher BER.
>
> If I am running some other protocol I may require a lower BER.
>
> I always believe in giving the customer as much choice as
> possible.  I don't
> we should play god and decide before hand what is the best BER for our
> customers.
>
> Bill
>
>
>
> -------------------------------------------
> Bill St Arnaud
> Director Network Projects
> CANARIE
> bill.st.arnaud@xxxxxxxxxx
> http://tweetie.canarie.ca/~bstarn
>
>  
>
>  
>
>
>
> > -----Original Message-----
> > From: owner-stds-802-3-hssg@xxxxxxxxxxxxxxxxxx
> > [mailto:owner-stds-802-3-hssg@xxxxxxxxxxxxxxxxxx]On Behalf Of Rich
> > Seifert
> > Sent: Friday, May 28, 1999 2:53 PM
> > To: Jaime Kardontchik; Chang, Edward S;
> > stds-802-3-hssg@xxxxxxxxxxxxxxxxxx
> > Subject: Re: 1000BASE-T PCS question
> >
> >
> >
> > At 9:11 AM -0700 5/27/99, Jaime Kardontchik wrote:
> > >My impression is that it would have been much more simpler if
> > the group had
> > >been called "10-Gigabit-Ethernet" instead of "Higher-Speed
> > Group". At some
> > >time in the future the group will have to decide what kind of
> > standard to work
> > >on.
> > >
> >
> > Well, it was not clear at all (and still is not clear) that a
> > single-speed of
> > 10 Gb/s is the goal of all of the study group members, or
> indeed reflects
> > the needs of the user community. It is one of the purposes of the Study
> > Group to determine what speed(s) should be supported in a standard.
> >
> > >Ethernet standards deliver a BER of 10^(-10).
> > >
> >
> > This is simply not true. The BER spec for 10BASE5 is 10^-9. For
> > 10BASE2 and
> > 10BASE-T, it is 10^-8. For 100BASE-X and 1000BASE-X, it is 10^-12.
> >
> > The BER goals for any higher-speed standard should be determined
> > by the SG.
> > Further, BER is really a parameter more relevant to serial transmission
> > systems that do not use any block-coding; in such systems it is
> > straightforward to map between the BER and the Frame Loss Rate (a more
> > significant parameter in a connectionless, best-effort frame delivery
> > system). We had long discussions both in Fast Ethernet and
> > 1000BASE-T about
> > how many frame errors are generated by a single bit error, the
> > relationship
> > between symbol errors and bit errors, etc. In the end, the only
> observable
> > characteristic at the MAC service interface is the Frame Loss Rate. I
> > propose that any future standards work use this parameter to
> characterize
> > the error performance of the system, rather than BER.
> >
> > --
> > Rich Seifert                    Networks and Communications Consulting
> > seifert@xxxxxxxxxx              21885 Bear Creek Way
> > (408) 395-5700                  Los Gatos, CA 95033
> > (408) 395-1966 FAX
> > "... specialists in Local Area Networks and Data Communications systems"
> >
> >
>