On Apr 7, 2008, at 1:00 PM, Kevin Oberman wrote:
Date: Mon, 7 Apr 2008 20:21:26 +0530 From: "Glen Kent" <glen.kent@gmail.com> Sender: owner-nanog@merit.edu
says the solemn headline of Telegraph.
http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2008/04/06/ninternet106...
Also related to this one, here:
"Web could collapse as video demand soars" http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2008/04/07/nweb107.xml
.. and we in Nanog are still discussing IPv6! ;-)
Sigh. Never let a clueless writer put up a story as technically complex as this. He clearly does not know the difference between the web (which WAS invented at CERN) and the Internet (which was not). His confusion on this and other details leads to a story which has little or nothing to say.
1. The grid was NOT invented at CERN, although CERN/LHC people were involved.
2. Aside from being the a huge physics experiment, it is also a huge network experiment. We will be carrying many gigabits of data from CERN to FermiLab and Brookhaven as well as from those facilities to physics researcher all over the world. By 2011 we may be seeing close to 100 Gbps 24/7 for months at a time. And that is just data from CERN to the US. They will be sending data to many other countries. (OK, there are some short pauses for calibration.)
3. This will all be over the Internet, though much will utilize dedicated lines purchased/leased just for this. But it's still TCP/IP and UDP (mostly the former) and mostly using traditional P2P techniques to get adequate performance over links with RTTs in excess of 200 ms.
It is true that the problems faced by CERN are similar to those faced by CDNs streaming video, but it is different in that this data is NOT streamed. You can't take the chance that the packet with the Higgs Boson waving "hello" is dropped.
I would actually disagree with that, _IF_ your SNR is limited by your bit rate. In VLBI (where the SNR _IS_ limited by the bit rate) it is more efficient to send more (new) data than to repeat old data that gets lost. Having talked to particle physicists here who feel that they are in the same regime, I would be curious as to whether or not CERN has done the math on this, and with what result. Regards Marshall
Since almost of the traffic is passing over dedicated links, congestion due to aggregation, the big issue with streaming video, is simply not an issue. We want to move as much data in a single "stream" as you can convince TCP to allow.
So the things learned from the LHC network experiment may well help improve the Internet and help with things like video distribution, the grid is NOT going to replace the web, let alone the Internet. -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: oberman@es.net Phone: +1 510 486-8634 Key fingerprint:059B 2DDF 031C 9BA3 14A4 EADA 927D EBB3 987B 3751