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Re: Long distance links




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/