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Re: Long distance links




Dae,

All of the them.

Thank you,
Roy Bynum
MCI WorldCom

Dae Young KIM wrote:

> Sorry for cutting in, but please repeat my question to Roy.
>
> Roy,
>
> Now what exactly is your primary concern? Speed? Line code? Or management? Or cost?
>
> Or would you say all of them? Oh, please no. If then, please one by one. Your such
> all-in-one attempt is likely to kill all other salient aspects of LAN; LAN speed, LAN
> codes, LAN managent, and LAN cost.
>
> Roy Bynum wrote:
>
> > Rich,
> >
> > I have read nothing from you that proves that a 9.548 MAC with scramble encoding will
> > be inherently more expensive than an 10.000 MAC with block encoding.  On the contrary,
> > why would an encoding scheme that only adds 4% overhead be more expensive than one that
> > adds 25% overhead.  For that matter, why would a PHY that does not require the data
> > processing of each byte with special symbols as part of a block encoding scheme be more
> > expensive than one that does?  Why would a PHY that adds active overhead every 125us be
> > more expensive than one that adds active overhead every 1.25ns?  If you are referring
> > to the cost of the lasers, it is the same cost for both types of PHYs, other than that
> > the block encoded PHY has a laser with a slightly higher signal insertion rate.
>
> --
> Dae Young KIM
> http://ccl.chungnam.ac.kr/~dykim/