Re: Long distance links
Sorry for retransmit to add my signature.
Roy:
It seems you are stating that the WAN/PHY has been developed by telephone
venders (to be absorbed as a freebie), and the WAN/PHY will be required only
at the LAN-to-WAN switch, which is located at the LAN and WAN interconnecting
point. Furthermore, the WAN/PHY is using Ethernet frame with only 0.25% of
the SONET overhead. This is great. I believe this is what we want. If you
can summarize into a proposal, we can start to work on it.
The other issues are trivial.
I do not appreciate the significance of the 500 meter MM fiber to the WAN/PHY
vs WAN/PHY issue.
I believe Ethernet is not low-tech, rather a product by well seasoned, and
experienced engineers pushing the technology to the limit of simplicity, and
yet reliable. It is an art which not every one can achieve to that level.
To make it work at any cost is an easy assignment which any on can do it.
The LAN market size ($28 billion), and WAN market size ($280 billion) were
published in the "Business Week," September issue of last week. I thought
many people are interested in the figures.
Ed Chang
NetyWorth technologies, Inc.
EChang@xxxxxxxxxxxxxxxx
>
> 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.
>
> Thank you,
> Roy Bynum
> MCI WorldCom
>
> NetWorthTK@xxxxxxx wrote:
>
> > Roy:
> >
> > In spite of differences, we all have one thing in common, which is to
> connect
> > all the global Ethernet LAN sites together through WAN at the most
> > cost-effective method. LAN people are determined to extend their $28
> billion
> > market into the $230 billion WAN market. So far, we are trying to
achieve
> > the same goal by making the conversion from LAN to WAN, simple, and low
> cost.
> >
> > I tried to find out where is our difference? The difference is whether
we
> > should be responsible for "LAN to WAN conversion" only, or we should also
> > extend our responsibility to assure the installed bases are preserved
> without
> > added cost.
> >
> > I believe the objective is clear -- the latter one is correct.
> >
> > Your proposal of "WAN compatible PHY" is to make 10GbE PHY = WAN PHY,
> which
> > will impose 9.58..Gbps, NRZ scramble code and SONET OAM into IEEE 802.3
> 10GbE
> > standard. I think we like to keep IEEE 802.3 an Ethernet standard, but
> not a
> > SONET standard.
> >
> > In order to make this "WAN compatible PHY" to talk to the rest of
Ethernet
> > LANs, the "LAN to WAN conversion" will take place in every individual
> > Ethernet terminals, which add unnecessary cost to the installed bases.
> >
> > I am not reasoning the WAN/PHY is much more expensive than a LAN/PHY,
but
> I
> > am reasoning the unnecessary cost added to each terminals. They should
be
> > tranparent from the LAN-to-WAN conversion issue -- no change.
> >
> > Why we cannot locate your "WAN compatible PHY" at only one location at
the
> > LAN entering point from WAN. That will do exactly what you want to do --
> > Ethernet Frame, 9.584. Gbps, some kind of OAM to deal optical fault
issues.
>
> > I have not seen any good reason to insist that the conversion should be
> > located inside the LAN.
> >
> > We need a LAN/PHY to keep 10/100/1000/10000 Mbps compatible. We
> definitely
> > need WAN/PHYs to interconnect all Ethernet LANs together, which the
strong
> > market demand will create, with or without us anyway. I believe what
you
> are
> > proposing is that HSSG is the logical body at the right moment to create
> it.
> > I would agree.
> >
> > Therefore, we need both LAN/PHY and WAN/PHY?
> >
> > Regards,
> >
> > Ed Chang
> > NetWorth Technologies, Inc.
> > EChang@xxxxxxxxxxxxxxxx
> >
> >