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Ali,
I'd like to understand where you got the 5M port count for
GbE when 10GbE started. From my recollection, 10GbE started with the CFI
in November 1998 which was the same year 802.3z was ratified and prior to the
ratification of 802.3ab (1000BASE-T). And 1000BASE-T devices saw limited
deployment after the standard was ratified due to lack of shipping
product.
Was 10GbE started too early? Given the market hype at
the time and the lack of crystal balls, it wasn't. Hindsight is 20/20, so
it is easy to make judgements now about past decisions on when to start the
effort. There's market demand now for something faster than 10GbE and
given the time it takes to do a project like this, in my humble opinion, HSSG is
starting at the right time.
Cheers,
Brad
Mike
Please see my comments below
Mike Bennett
wrote:
Ali,
Ali
Ghiasi wrote:
Mike and
Jugnu
You both have some very good points. On one hand we have the
high performance computing demanding highest bandwidth
achievable but on
the other hand Jugnu brings up the fundamental requirement for having
successful Ethernet standard "mass market potential".
I would
say cost-effectively achievable. Bell labs demonstrated multi-terabit
transmission in 2000, but that system wasn't/isn't a product, we can't buy it,
(or afford it if it were a real product), nor do we need it now for that
matter.
I expect this was some type of DWDM network, which one
can even apply to 10Gig Ethernet right now.
Mike also
mentions this project will take 3.5-5 years, IEEE project traditionally have
not taken this long this means then we are
too early. I
have to disagree. If you include the time spent by study groups, several
projects fall within that range. I expect this study group to take a
year. Add 2.5-3.5 years to get through 5 drafts of a standard and again
we're right in the range I've stated.
Based on input I've seen
from end users, taken from a survey prior to the CFI, I believe we've started
just in time.
When we started 10Gig E the volume for 1
Gig E had already exceed 5 million ports. In the HSSG meeting several
people indicated we started 10Gig E to early, in 2006 by best estimate for
10Gig volume shipment will be <10% of the
1Gig E volume when 10Gig E was
started. If there is such a huge market for 100 Gig E then the current
market for
10Gig E should be 10x as huge.
For example
when 802.3ae was started in the 1999 10Gig lasers/modulators existed for
more than
15 years prior.
Then 10G should not have
been so "expensive" nor slow on market uptake since we reused existing
components, right? I'm not quite sure what your point is.
The bubble of 1999/2000 created the marketing requirement for
10Gig E at time where the basic components for
10Gig had already existed for
some times. The real issue was cost, many more would have used 10Gig if
the
cost was just little bit more than 1Gig so this bring us to need vs nice
to have.
I have
listed dilemma we are facing:
- Implementing 100 Gig
in the near term means Nx10Gig
Having not seen a single
presentation regarding possible solutions to the problem, I wouldn't be so
sure this is the only cost-effective way to implement 100G (if that's the
speed we include in our objectives).
- Implementing 100Gig in few years the right
answer might be nx25Gig
and it might be something else.
I don't see your point.
- Carrier want to leverage their existing
DWDM layer which mean baudrate in the 9.95-12.5 Gig
- If LAG implemented why not allow n to be
4?
You must have heard the numerous complaints by now from the
people who actually have to live with operating and troubleshooting Link
Aggregation. Link-layer aggregation is an unacceptable
option.
When I referred to LAG I didn't meant exiting LAG,
but rather a more efficient method something between the MAC and
PCS
layer.
- Operation with different
width
- Backward compatibility XAUI, LX4
?
- Greatest bandwidth demands (100+Gig) are on VSR
links <50 m but the longer reach >10Km
may be
able to live with 4x10Gig.
All these means we should either define
some sort of scalable architecture or just define LAG method and
do not
define any PMDs!
I think it's a bit premature to come to this
conclusion, but it makes for lively
discussion.
Mike
Thanks,
Ali
Thanks,
Ali
Jugnu,
OJHA,JUGNU wrote:
Mike,
It seems
more reasonable to me to consider finally decoupling the physical
pipe size from the rigid hierarchy used in the past. Why not
simply define a scalable interface that allows inverse multiplexing
(physical layer aggregation – not the type of aggregation you have
described, which sounds like the current LAG) of an arbitrary
(within some bounds, obviously) number of physical channels (10G)
into a single logical link? The SONET/SDH and Digital
Wrapper/OTN world already has mechanisms to do this (VCAT, LCAS),
and dynamically to boot.
This would
provide a much more flexible, scalable solution to customers.
On the surface, it seems to
me that with flexibility comes complexity which leads to higher
cost. It's also not clear to me how the physical layer
aggregation you propose translates to a port on a switch. Would
I have to buy an N x 10G transceiver? Would it be a WDM-like
transceiver? Would this work with a single fiber-pair or
multi-strand? What would the relative incremental cost be (in
percentages, non monetary units) to scale up? Also, are
you proposing that this would scale beyond 100G? If so, how
far? You mention boundaries - I'm curious what you think the
upper bound would be. I hope you're planning to present
something at the interim as it would help me understand what
you're really proposing and how that compares to other
ideas.
Regards,
Mike
In
particular, it would allow them to grow capacity on any given link
as needed, instead of having to install 10x10G channels up front.
Further, when they hit 100G, they wouldn’t be stuck until some
other solution is defined – they could continue to grow.
Respectfully,
Jugnu Ojha
Avago
Technologies
John, et
al.,
>During our first
meeting, I anticipate spending a lot of time focusing on objectives.
At the
>closing plenary I highlighted two issues / objectives that the
SG would have to consider:
>
> Tradition of 10x leap in
speed
I think the speed increase has to be
10x. The standards development process will take at least 3.5
to 4 years to complete. Anything less than 100G will force
people who are currently aggregating 10G links to continue to use
aggregation, only using fewer higher-speed, and more expensive
links. End users prefer using a single link over
aggregating physical-layer links into a logical link because of the
complications that come with aggregation. The data in the CFI
presentation was just a sample of cases in which network operators
we're aggregating 10G links to accommodate the demand on their
networks. There will be many more by 2011 (when I expect there
would be 'real' products on the market).
> Multiple Reach
Targets
> It was also
presented that the focus of this effort wasn’t for a desktop
application, and >that the cost model needs to be
considered.
I believe we need to adjust the cost model in
such a way that it is aligned with the ecosystem. It is
unreasonable, in my opinion, to expect a 10x/3x model to apply to
systems designed for wide-area/metro-area networks. I also
think it's short-sighted to ignore the rest of the ecosystem and
develop Ethernet only in the part of the ecosystem where the
original cost model
applies.
Regards,
Mike -- Michael J. Bennett Sr. Network Engineer LBLnet Services Group Lawrence Berkeley Laboratory Tel. 510.486.7913 |
--
Michael J. Bennett
Sr. Network Engineer
LBLnet Services Group
Lawrence Berkeley Laboratory
Tel. 510.486.7913
|