Archive for the 'Routing' Category

Caidagram: visualizing geographically annotated Internet measurements

Monday, February 28th, 2011 by Claudio Squarcella

I post this article to describe the results of my five month visit to CAIDA and UC San Diego, and to thank the organizations that collaborated to make this work possible.


my first “Future Internet Architecture” PI meeting

Wednesday, January 5th, 2011 by kc

Among the interesting meetings I attended in 2010 was the principal investigators (PI) meeting for NSF’s new “Future Internet Architecture” (FIA) program. The FIA program builds on the successes of NSF’s previous Future Internet Design (FIND) program, the recommendations of a review panel, and a community summit in October 2009. (The FIND program itself has been integrated into NSF’s new Network Science and Engineering research program, while the four FIA teams are attempting to implement some of the ideas developed thus far.) CAIDA is participating in one of these projects — Named Data Networking (NDN), led by Van Jacobson at Xerox Parc and Lixia Zhang at UCLA. (Background links to 2010 technical report describing the proposed architecture, Van’s August 2006 video lecture and 2009 ACM Queue Q&A on NDN ideas.)


IP-AS mappings

Wednesday, July 28th, 2010 by Amogh Dhamdhere

We have performed an analysis of the IP-AS mapping obtained from Routeviews/RIPE collectors.

A crucial step in various research efforts that study the Internet infrastructure is to map an IP address to the Autonomous System (AS) to which it is assigned. The most common approach to map IP addresses to ASes is by using BGP table dumps from public repositories such as Routeviews and RIPE. We assign “ownership” of an IP address to the AS that originates the longest BGP prefix that matches the IP address. Routeviews and RIPE, however, have multiple collectors, each of which peers with a diverse set of ASes. Consequently, the IP-AS mapping obtained by using the BGP table dump from one collector could be different from that obtained from a different collector. The obvious solution is to aggregate views from as many vantage points as possible to obtain the most complete IP-AS mapping possible. In practice, however, it is common to use data from just one or two collectors, as it greatly simplifies the process of collecting and pre-processing data. The goal of our analysis is to compare different collectors, in terms of the different metrics that we are interested in, viz. address space coverage, IP-AS mapping, unique ASes, unique prefixes, unique more specific prefixes, AS links, and AS paths. Further, we study the utility of adding data from more collectors, in terms of the resulting change in the aforementioned metrics. Finally, we compare the IP-AS mapping from Routeviews and RIPE tables with that obtained from Team Cymru’s whois service.


‘academic’ thoughts about a ‘future Internet’

Monday, October 12th, 2009 by kc

This post is our submitted response to NSF’s call for expressions of interest in the Future Internet Architectures summit, which i am attending this week.

What scientific contributions will you bring to the discussion about Future Internet architectures?

As scientists, we are compelled to explore how the peculiar structure relates to the function(s) of complex networks. Many complex networks in nature share the peculiar structural character of the Internet, but they also manifest phenomenal behavior: they efficiently route information without any observable routing protocol overhead. This achievement is currently beyond the reach of man-made networks. The Internet still uses a 30-year old routing architecture with fundamentally unscalable overhead requirements.  Yet in those 30 years, the Internet’s inter-domain topology has evolved toward a structure for which nature has superior routing technology, if only we can figure out how to use it!


spoofer: measure your network’s hygiene!

Sunday, April 5th, 2009 by kc

Update: In May 2015, ownership of Spoofer transferred from MIT to CAIDA

We are studying an empirical Internet question central to its security, stability, and sustainability: how many networks allow packets with spoofed (fake) IP addresses to leave their network destined for the global Internet? In collaboration with MIT, we have designed an experiment that enables the most rigorous analysis of the prevalence of IP spoofing thus far, and we need your help running a measurement to support this study.

This week Rob Beverly finally announced to nanog an update to spoofer he’s been working on for a few months. Spoofer is one of the coolest Internet measurement tool we’ve seen in a long time — especially now that he is using Ark nodes as receivers (of spoofed and non-spoofed packets), giving him 20X more path coverage than he could get with a single receiver at MIT.


what percentage of traffic on the Internet is peer-to-peer file sharing?

Sunday, February 8th, 2009 by kc

I get this question as often as I get any question about the Internet. finally, a visiting intern Mia Zhang from Beijing Jiaotung University has done a thorough literature roundup, extracting the best available data pertinent to this question that she could find in the public domain.

(more…) covers caida’s recent work in Nature

Wednesday, January 14th, 2009 by kc

As a follow-up to the recent press flurry about Dima’s routing research, Voice of San Diego interviewed us for several hours last week, and no doubt spent twice that time focused on trying to get a complex story mostly right. Hyperbolic headlines notwithstanding, the journalist who interviewed us, David Washburn, did an outstanding job of fact-checking and making sure he accurately represented our views. If this is the future of journalism, I’m not the least bit worried about the death of 20th century journalism models. The real fourth estate is in good hands.

in (re)search of scalable routing..

Tuesday, January 6th, 2009 by kc

I’ve written before about the growing consensus among experts that the Internet’s underlying communications routing algorithms are fundamentally unscalable, so I am delighted to have CAIDA’s routing research group led by Dima Krioukov achieve some fundamental routing research results worth extensive media coverage. We have not solved the Internet’s routing scalability problem, but these recent discoveries will help that cause.


internet telemetry, v6

Wednesday, December 10th, 2008 by kc

i gave a (faster, less understandable) version of this talk (pdf or slides+audio quicktime) at the October 2008 ARIN meeting in Los Angeles (original October version) and again to ISOC’s advisory council meeting in November. motivation: the end of the current addressing architecture, with scant understanding of how to retain all its positive features in the face of inevitable change. a topic i worry about more each year.

(peter cincotti sings as if we knows what we’re going through.)

recommended reading in internet technology policy

Saturday, August 9th, 2008 by kc

(gathered earlier this year upon a student’s request)

  1. Abatte, Janet. Inventing the Internet. 2000.
  2. Benkler, Yochai. The Wealth of Networks. 2006.
  3. Benkler, Yochai. Freedom in the COMMONS: Towards a Political Economy of Information., Duke Law Journal. 2003.
  4. Brin, David. Transparent Society. 1999.
  5. (more…)