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Re: Long distance links


Now I think it's time for your clearly define what the WAN PHY is, before continuing
further confusing arguments back and forth.

What really is the WAN PHY that you mean? Please define it lest further
misunderstanding of each other.

Roy Bynum wrote:

> Ed,
> Where do you get the idea that the WAN to LAN conversion will occur at every
> terminal?  The common denominator for the WAN PHY and the legacy LAN is the 802.3
> frame.  Existing LAN technology and future installations will in no way be
> effected by a WAN compatible PHY interface on the other side of a data switch.
> Where does the idea that Ethernet's common denominator is 10/100/1000/10000mb come
> from.  Ethernet started at 2.4mb, not 10mb.  The common denominator is the
> 802.3/Ethernet frame, which is not changing.
> Do we need a LAN only PHY, yes.  Will a LAN only 500m MMF PHY, at 10.00mb traffic
> data rate, be less expensive than a 500m MMF WAN compatible PHY; maybe not.  No
> one has done an economic model yet.  Most of the development of a WAN compatible
> PHY has already been done.  That cost was absorbed by the telephony vendors.  It
> is almost a "freebie".  All that is left is the cost of the MAC to WAN compatible
> PHY interface development.  Time to market for the WAN compatible PHY is dependent
> only on the standardization of that interface.  Development on a LAN only PHY has
> not fully started yet, and has been paid for yet.
> As for saving cost, both in equipment and support requirements, I am adamantly
> committed to just that!  In addition to the inexpensive interfaces, Ethernet has
> gained dominance in the market because of its low-tech, plug and play support
> architecture.  This is exactly what I want to continue in the LAN and extend it to
> the WAN/MAN!
> Where does everyone keep keep coming up with the idea that a 10GbE WAN compatible
> PHY will have SONET OAM&P on it.  It will NOT have SONET OAM&P.  Most, almost
> 99.7%, of the SONET OAM&P functionality will not exist in a 10GbE WAN compatible
> PHY.  Of the 1755 overhead bytes that exist in SONET OC192, only 4, maybe 5, will
> be active in a 10GbE WAN compatible PHY.  That is the reason that I refer to it as
> a WAN compatible PHY, NOT as an Ethernet mapped SONET PHY.
> The global WAN/MAN/LAN data market is a multi trillion dollar market, not a 280
> billion dollar market.  The 280 billion dollar figure is for the USA only.  If the
> 10GbE WAN compatible PHY is done properly, it will be compatible to all
> transmission/DWDM systems on a global scale.

Dae Young KIM