RE: 850 nm solutions
I agree XAUI should be 100% transparent. XAUI has its unique value in 10
Gbps serial application to maintain symbol rate at 10.3125 which is very
close to 10 Gbps. However, it comes with a lot of complicated coding
For CWDM approach, the data rate is low which, does need XAUI approach. The
straight forward, mature, and market-proved block code will do nice job. In
the reference model, it will completely skip the XAUI of 64b/66b, and the
MAC will go directly to 8B/10B coding (PCS) followed by SERDES (PMA). Just
the same as GbE ... simple and cost-effective.
If the XAUI proposal is trying to make all applications using XAUI of
64b/66b, it is a wrong approach. Keep it flexible. Not everyone needs the
complex manipulation of the coding scheme.
Edward S. Chang
NetWorth Technologies, Inc.
[mailto:owner-stds-802-3-hssg@xxxxxxxx]On Behalf Of Roy Bynum
Sent: Wednesday, May 03, 2000 1:28 AM
To: THALER,PAT (A-Roseville,ex1); stds-802-3-hssg@xxxxxxxx
Subject: Re: 850 nm solutions
There is nothing evil about economic and business considerations. I
recognize the economic advantage of developing silicon that
will work in multiple standards. I recognize that the cost of talented
personnel along with other manufacturing and competitive
issues tends to favor reduction of diversity. I recognize that there may
be individuals in the P802.3ae TF that stand to benefit
directly, or whose company would benefit economically depending on how the
standard is defined. There is nothing evil about that.
As a customer, the only benefit that I or the company that I work for
receives, is the manor in which the users would be enabled by
As a customer who deploys very high bandwidth and extremely large networks,
I want consistent standards, but I want them specialized
for the functions they are to perform. Over the years, the larger vendors
have created more "generalized", like Microsoft's Windows
NT. For mediocre desktop and server usage it will do. For people that
require better or more reliable performance go to other
vendors and products. While this may not have greatly effected Microsoft's
market in low end systems, it has almost no share in the
very high end technology market. 10GbE is targeted at the high end
technology market. The 10GbE WAN compatible PHY is targeted for
an extremely large but very specialized market. As a representative
customer of that high end technology industry market, I would
prefer to have what I need in the standard, "up front". Instead I may have
to shop around for vendors that will deviate from that
standard in order to deliver what is required, much like some large
customers requiring vendors to support jumbo frames. This was
also the comment by another customer concerning the need for short reach
The majority of the individuals in the P802.3ae TF are "LAN" people. They
understand the needs of a LAN only PHY. There are some
that also work with WAN systems. Both the "LAN" and "WAN" people recognize
that the needs are different between LAN systems and WAN
systems. An attempt to combine the LAN and WAN into one "UniPHY" will
result in a standard that does not properly address the needs
of either the LAN or the WAN.
Last year, 1.6 terabit per second DWDM systems were field tested. Those
transport systems can provide 160 10GbE WAN channels per
fiber. Internet content sites are increasing exponentially all over the
world, with aggregated transport bandwidths getting into
the 10s of terabits per second per site. Facilities floor space density is
becoming a critical issue. The port density as well as
per port bandwidth on data switches and servers is becoming a critical
issue. The complexity of intra-cluster port usage in storage
servers as well as data switches is becoming a critical issue. All of this
is leading to the need for data switches with multiples
of terabits per second in aggregate bandwidth per chassis, and interface
cards with multiple 10Gb ports each.
The industry needs very condensed form factor equipment, the kind that will
not need to have 18" of etch between the MAC and PCS.
The industry needs a protocol that has as much bandwidth efficiency as
possible because the transport signaling speed is fixed.
The industry needs transport operations and performance management based on
existing systems so that it does not have to deploy
entirely greenfield operations support systems as well as untried greenfield
It is the above reasons that I, as a customer, have taken a stand that XAUI
should be 100% transparent as far as the standard is
concerned. This will allow vendors in the future to build very high density
systems, with small form factors per port, without the
additional symbol overhead that a non-transparent XAUI would put on non-XAUI
MAC/PCS interfaces. At the same time, a transparent
XAUI will allow vendors to build systems today that do need the extended
etch distance. As a customer, I have taken a stand that
the LAN PHY and the WAN compatible PHY should be separate tracks within
P802.3ae, according to the objectives as written. This will
allow for short reach block encoded parallel solutions for the LAN PHY and a
single serial scrambled synchronous solution for the
WAN compatible PHY. As a customer, I have also taken a stand that the SONET
mapping proposal by Paul Bottroff and David Martin,
modified to allow for 10Byte IPG compression, be standardized instead of the
64B/66B block encoding for the WAN compatible PHY.
This will allow for the highest data transfer bandwidth available with the
shortest amount of time to market.
----- Original Message -----
From: THALER,PAT (A-Roseville,ex1) <pat_thaler@xxxxxxxxxxx>
To: Roy Bynum <rabynum@xxxxxxxxxxxxxx>; THALER,PAT (A-Roseville,ex1)
<pat_thaler@xxxxxxxxxxx>; Rick Walker
Sent: Monday, May 01, 2000 7:05 PM
Subject: RE: 850 nm solutions
> This is a frustrating discussion. You seem intent on twisting what is said
> and implying evil actions. I did not say different groups developed Hari
> XAUI. What I said is that the Infiniband TA did not develop Hari. I should
> know, I've been there from the beginning and in the Future IO before that.
> Over my career, I've seen a number of times when separate groups applied
> existing technologies to the same or similar problems and came up with
> similar solutions. For instance, there were about 4 proposals for 10BASE-T
> developed independently by different companies that when examined were
> almost identical. It wasn't because we co-developed them. It was because
> taking as a departure point what we had learned about twisted-pair cable
> as an industry and applying that to how to run Manchester code over it,
> a certain direction was fairly attractive and 4 out of 6 companies
> it came up with very similar solutions. There were minor differences such
> choice of where to put the equalizer, but mostly it was the same solution.
> That is the source of much of the "commonality" to which you refer.
> "Hari" was developed with Ethernet in Fibre Channel in mind (to the best
> understanding; I did not work in that group). But Hari as a name really
> didn't fit into the names 802.3 has used for interfaces. Therefore, a
> based on the Hari work suggests "XAUI" as a name that does fit in with
> traditional Ethernet interface names.
> I have no idea what you are talking about when you talk about different
> groups with the same people. Your statement about voting blocks is totally
> unjustified and offensive.
> Pat Thaler