I am not normally on this list but someone kindly gave me copies of some of the email 
concerning the Internet2 Land Speed record. So I have joined the list.

As one of the PIs of the record, I thought it might be useful to comment on a few 
interesting items I have seen, and no I am not trying to flame anybody:

"Give  em a million dollars, plus fiber from here to anywhere and let me muck with the 
TCP algorith, and I can move a GigE worth of traffic too - Dave"

You are modest in your budgetary request. Just the Cisco router (GSR 12406) we had on 
free loan listed at close to a million dollars, and the OC192 links just from 
Sunnyvale to Chicago would have cost what was left of the million/per month.

We used a stock TCP (Linux kernel TCP).  We did however, use jumbo frames (9000Byte 
MTUs).

In response Richard A Steenbergen we are not "now living in a tropical foreign 
country,  with lots and lots of drugs and women" but then the weather in California is 
great today.

"What am I missing here, theres OC48=2.4Gb, OC192=10Gb ..."

We were running host to host (end-to-end) with a single stream with common off the 
shelf equipment, there are not too many (I think none) > 1GE host NICs available today 
that are in production (e.g. without signing a non-disclosure agreement).

"Production commercial networks ... Blow away these speeds on a regular basis". 
See the above remark about end-to-end application to application, single stream.

"So, you turn down/off all the parts of TCP that allow you to share bandwidth ..." 
We did not mess with the TCP stack, it was stock off the shelf.

"... Mention that "Internet speed records" are measured in terabit-meters/sec." 
You are correct, this is important, but reporters want a sound bite and typically only 
focus on one thing at a time. I will make sure next time I talk to a reporter to 
emphasize this. Maybe we can get some mileage out of Petabmps (Peta bit metres per 
second)  sounds

"What kind of production environment needs a single TCP stream of data at 1Gbits/s 
over a 150ms latency link?" 
Today High Energy Particle Physics needs hundreds of Megabits/s between California and 
Europe (Lyon, Padova and Oxford) to deliver data on a timely basis form an experiment 
site at SLAC to regional computer sites in Europe. Today on production acadmeic 
networks (with sustainable rates of 100 to a few hundred Mbits/s) it takes about a day 
to transmit just over a Tbyte of data which just about keeps up with the data rates. 
The data generation rates are doubling / year so within 1-3 years we will be needing 
speeds like in the record on a production basis. We needed to ensure we can achieve 
the needed rates, and whether we can do it with off the shelf hardware, how the hosts 
and OS' need configuring, how to tune the TCP stack or how newer stacks perform, what 
are the requirements for jumbo frames etc. Besides High Energy Physics other sciences 
are beginning to grapple with how to repliacte large databases across the globe, such 
sciences include radio-astronmoy, human genome, global
weather, seismic ...

The spud gun is interesting, given the distances, probably a 747 freightliner packed 
with DST tapes or disks is a better idea.  Assuming we fill the 747 with say 50 Gbps 
tapes (disks would probably be better), then if it takes 10 hours to fly from San 
Francisco (BTW Sunnyvale is near San Francisco not near LA as one person talking about 
retiring to better weather might lead one to believe) the bandwidth is about 2-4 
Tbits/s. However, this ignores the reality of labelling, writing the tapes, removing 
from silo robot, pocaking, getting to airport, loading, unloading, getting through 
customs etc. In reality the latency is really closer to 2 weeks. Even worse if there 
is an error (heads not aligned etc.) then the the retry latency is long and the effort 
involved considerable.  Also the network solution lends itself much better to 
automation, in our case we saved a couple of full time equivalent people at the 
sending site to distribute the data on a regular basis to our collaborator sites
in France, UK and Italy.

The remarks about window size and buffer are interesting also.  It is true large 
windows are needed. To approach 1Gbits/s we require 40MByte windows.  If this is going 
to be a problem, then we need to raise question like this soon and figure out how to 
address (add more memory, use other protocols etc.). In practice to approcah 
2.5Gbits/s requires 120MByte windows.

I am quite happy to concede that this does not need to be about some jocks beating a 
record. I do think it is important to catch the public's attention to why high speeds 
are important, that they are achievable today application to application (it would 
also be useful to estimate when such speeds are available to universities, large 
companies, small companies, the home etc.), and for techies it is important to start 
to understand the challenges the high speeds raise, e.g. cpu and router memories, bugs 
in TCP, OS, application etc., new TCP stacks, new (possibly UDP based) protocols such 
as tsunami, need for 64 bit counters in monitoring, effects of the NIC card, jumbo 
requirements etc., and what is needed to address them. Also to try and put it in 
meaningful terms (such as 2 full length DVD movies in a minute, that could also 
increase the "cease and desist" legal messages shipped ;-)) is important. 

Hope that helps, and thanks to you guys in the NANOG for providing todays high speed 
networks.

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