With IPv6 Launch approaching, there is increasing interest in measuring the readiness of the IPv6 infrastructure. A major concern, particularly for networks that source or sink content, is the performance that is achievable over IPv6, and how it compares to the performance over IPv4. A recent study by Nikkah et al. argues that data plane performance, as measured by web page download times, is largely comparable in IPv4 and IPv6, as long as the AS-level paths in IPv4 and IPv6 are identical.  We have confirmed these findings with our own measurements covering 593 dual-stack ASes: we found that 79% of paths had IPv6 performance within 10% of IPv4 (or IPv6 had better performance) if the forward AS-level path was the same in both protocols, while only 63% of paths had similar performance if the forward AS-level path was different.

Given the apparent importance of congruent AS-level paths in IPv4 and IPv6, we measured to what extent such congruence exists today, and how this has evolved historically. We measure IPv4 and IPv6 AS paths from seven vantage points (ACOnet/AS1853, IIJ/AS2497, NTT/AS2914, Tinet/AS3257, HE/AS6939, AT&T/AS7018, NL-BIT/AS12859) which have provided BGP data to Routeviews and RIPE RIS since 2003. The figure below plots the fraction of dual-stack paths that are identical in IPv4 and IPv6 from each vantage point over time. According to this metric, IPv6 paths are maturing slowly. In January 2004, 10-20% of paths were the same for IPv4 and IPv6; eight years later, 40-50% of paths are the same for six of the seven vantage points.

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Our recent study of the evolution of the Internet ecosystem over the last twelve years (1998-2010) appeared in the IEEE/ACM Transactions on Networking in October 2011. Why is the Internet an ecosystem? The Internet, commonly described as a network of networks, consists of thousands of Autonomous Systems (ASes) of different sizes, functions, and business objectives that interact to provide the end-to-end connectivity that end users experience. ASes engage in transit (or customer-provider) relations, and also in settlement-free peering relations. These relations, which appear as inter domain links in an AS topology graph, indicate the transfer of not only traffic but also economic value between ASes. The Internet AS ecosystem is highly dynamic, experiencing growth (birth of new ASes), rewiring (changes in the connectivity of existing ASes), as well as deaths (of existing ASes). The dynamics of the AS ecosystem are determined both by external business environment factors (such as the state of the global economy or the popularity of new Internet applications) and by complex incentives and objectives of each AS. Specifically, ASes attempt to optimize their utility or financial gains by dynamically changing, directly or indirectly, the ASes they interact with.

The goal of our study was to better understand this complex ecosystem, the behavior of entities that constitute it (ASes), and the nature of interactions between those entities (AS links). How has the Internet ecosystem been growing? Is growth a more significant factor than rewiring in the formation of new links? Is the population of transit providers increasing (implying diversification of the transit market) or decreasing (consolidation of the transit market)? As the Internet grows in its number of nodes and links, does the average AS-path length also increase? Which ASes engage in aggressive multihoming? Which ASes are especially active, i.e., constantly adjust their set of providers? Are there regional differences in how the Internet evolves?

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On the heels of our recent press release regarding fresh publications that  make use of the UCSD Network Telescope data, we would like to take a moment to thank the institutions that have helped preserve this data over the last eight years. Though we recently received an NSF award to enable  near-real-time sharing of this data as well as improved classification, the award does not cover the cost to maintain this historic archive. At current UCSD rates, the 104.66 TiB would cost us approximately $40,000 per year to store. This does not take into account the metadata we have collected which adds roughly 20 TB to the original data.  As a result, we had spent the last several months indexing this data in preparation for deleting it forever.

Then, last month, I had the opportunity to attend the Security at the Cyberborder Workshop in Indianapolis. This workshop focused on how the NSF-funded IRNC networks might (1) capture and articulate technical and policy cybersecurity considerations related to international research network connections, and (2) capture opportunities and challenges for the those connections to foster cybersecurity research.  I did not expect to find a new benefactor for storage of our telescope data at the workshop though, in fact, I did.

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We were happy to see the coverage of UCSD’s press release describing two papers we recently published, introducing new methods and applications for analyzing dark net data (aka “Internet background radiation” or IBR).  The first paper, “Analysis of Country-wide Internet Outages Caused by Censorship”, presented by author Alberto Dainotti last November at IMC 2011, focused on using IBR in conjunction with other data sources to reveal previously unreported aspects of the disruptions seen during the uprisings of early 2011 in Egypt and Libya. The second paper, “Extracting benefit from harm: using malware pollution to analyze the impact of political and geophysical events on the Internet”, published in ACM SIGCOMM CCR (January 12), used IBR data observed by UCSD’s network telescope to characterize Internet outages caused by natural disasters. In both cases the analysis of this (mostly malware-generated) background traffic contributed to our understanding of events unrelated to the malware itself. Our press release was picked up by several online publications, including The Wall Street Journal Blog, ACM Technews, Communications of the ACM Web site, Spacedaily, Physorg, Tom’s Guide, Product Design & Development, Newswise, Domain-b, EurekAlert, Eurasia review, Security-today.com, Everything San Diego, Spacewar Cyber War.

The papers are also available on CAIDA’s publications page.

As part of our NSF-funded network research project on modeling Internet interconnection dynamics, we hosted the second Workshop on Internet Economics (WIE2011) last December 1-2. The goal of the workshop was to bring together network technology and policy researchers with providers of commercial Internet facilities and services (network operators) to further explore the common objective of framing an agenda for the emerging but empirically stunted field of Internet infrastructure economics. The final report (http://www.caida.org/publications/papers/2012/wie11_report/) attempts to capture the content, structure, and depth of the discussions, and presents relevant open research questions identified by workshop participants. From the intro (but the 5-page pdf is worth reading):
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Reading about NASA’s recent DNSSEC snafu, and especially Comcast’s impressively cogent description of what went wrong (i.e., a mishap that seems way too easy to ‘hap’), I’m reminded of the page I found most interesting in The Checklist Manifesto:

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Finally, a process we started almost three years ago has reached a milestone: the first public draft of The Menlo Report: Ethical Principles Guiding Information and Communication Technology Research and its Companion Report were posted on the DHS and SRI web sites (respectively) last month.

DHS’s Science and Technology Directorate, through its PREDICT program, sponsored this report on ethics in Information and Communication Technology Research (ICTR). The culmination of a multi-year effort by network and security research stakeholders to lay out a guiding framework to identify, navigate, and resolve ethical issues in ICTR, this report is intended to be a dialogue launch point for the community of researchers, oversight entities, and policymakers to reflect on ethical issues in security and network research. Public comments are encouraged via the Federal Register through 27 February 2012. I’m pretty sure all comments are responded to and/or integrated into the next version of this report. Hopefully the report will also be the topic of discussion at some conferences and workshops this year, so that the community can get out ahead of these issues before we find ourselves facing legislative overreaction to catastrophe (or even perceived catastrophe). Please consider reading and submitting a comment.

I kicked off 2012 with a visit to Colorado State University in Fort Collins, CO to attend the principal investigators (PI) retreat for the Named Data Networking Project, one of four projects funded under NSF’s “Future Internet Architecture” (FIA) program. Impressive progress since the first FIA meeting, with substantial development and coordination of the NDN Testbed connecting the initial participating institutions, including network status reporting, state of (phase-one) OSPF routing, and testbed status pages. This two-day meeting packed in a wide range of collaborative discussions of architecture and implementation issues, including: topology and namespace structure and constraints; organizational structure and network management; routing and forwarding strategy; security issues such as attribution and privacy; early experiences with application development; evaluation and measurement; social and ethical values in technology design; and educational outreach (classes teaching NDN concepts). We also discussed how to dispel the misconception that NDN is simply collaborative web caching. (The caching is essential but the most revolutionary piece of this new communication model is retrieving data by names.)

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I ended 2011 with a short (20 December) visit to a pleasantly warm Washington, D.C. for my 5th FCC Technical Advisory Council meeting. Some of the discussions from the third meeting were extended, others cut off for lack of time. We spent over an hour on the suggestion made by the Legacy Transition working group two meetings ago to advise the FCC to move forward in sunsetting (although we shunned that term at this meeting — “It’s a new beginning, not an end!”) the public-switched telephone network (PSTN). Many questions have arisen repeatedly in the discussions over the course of the last two meetings (and two FCC workshops in between), notably, “What happens to the telephony numbering system?” The initial strategy was imprecise, “The numbering plan will continue to exist but governance and allocation process needs to be considered.” Another repeated question has been “What exactly do we mean by PSTN?”

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The last line of this FCC announcement is ominous enough:

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