The paper “Selecting Representative IP Addresses for Internet Topology Studies” (available at http://www.isi.edu/~xunfan/research/Fan10a.pdf) was accepted to appear at the ACM Internet Measurement Conference 2010 in Melbourne, Australia.

From the abstract:

An understanding of Internet topology is central to answer various questions ranging from network resilience to peer selection or data center location. While much of prior work has examined AS-level connectivity, meaningful and relevant results from such an abstract view of Internet topology have been limited. For one, semantically, AS relationships capture business relationships and not physical connectivity. Additionally, many organizations often use multiple ASes, either to implement different routing policies, or as legacies from mergers and acquisitions. In this paper, we move beyond the traditional AS graph view of the Internet to define the problem of AS-to-organization mapping. We describe our initial steps at automating the capture of the rich semantics inherent in the AS-level ecosystem where routing and connectivity intersect with organizations. We discuss preliminary methods that identify multi-AS organizations from WHOIS data and illustrate the challenges posed by the quality of the available data and the complexity of real-world organizational relationships.

Citation: Xue Cai, John Heidemann, Balachander Krishnamurthy, and Walter Willinger. Towards an AS-to-Organization Map. In Proceedings of the ACM Internet Measurement Conference, p. to appear. Melbourne, Australia, ACM. November, 2010.

From the abstract:

Prior studies of Internet traffic have considered traffic at different resolutions and time scales: packets and flows for hours or days, aggregate packet statistics for days or weeks, and hourly trends for months. However, little is known about the long-term behavior of individual flows. In this paper, we study individual flows (as defined by the 5-tuple of protocol, source and destination IP address and port) over days and weeks. While the vast majority of flows are short, and most bytes are in short flows, we find that about 20% of the overall bytes are carried in flows that last longer than 10 minutes, and flows lasting 100 minutes or longer make up 2% of traffic. We show that long-lived flows are qualitatively different from short flows: they are generally slower, less bursty, and are due to different applications and protocols. We investigate the causes of short- and long-lived flows, and show that the traffic mix varies significantly depending on duration time scale, with computer-to-computer traffic more and more dominating in larger time scales.

Citation: Lin Quan and John Heidemann. On the Characteristics and Reasons of Long-lived Internet Flows. In Proceedings of the ACM Internet Measurement Conference. Melbourne, Australia, ACM. November, 2010. <http://www.isi.edu/~johnh/PAPERS/Quan10a.html>.

From the abstract:

Although the Internet is widely used today, we have little information about the edge of the network. Decentralized management, firewalls, and sensitivity to probing prevent easy answers and make measurement difficult. Building on frequent ICMP probing of 1% of the Internet address space, we develop clustering and analysis methods to estimate how Internet addresses are used. We show that adjacent addresses often have similar characteristics and are used for similar purposes (61% of addresses we probe are consistent blocks of 64 neighbors or more). We then apply this block-level clustering to provide data to explore several open questions in how networks are managed. First, we provide information about how effectively network address blocks appear to be used, finding that a significant number of blocks are only lightly used (most addresses in about one-fifth of /24 blocks are in use less than 10% of the time), an important issue as the IPv4 address space nears full allocation. Second, we provide new measurements about dynamically managed address space, showing nearly 40% of /24 blocks appear to be dynamically allocated, and dynamic addressing is most widely used in countries more recent to the Internet (more than 80% in China, while less than 30% in the U.S.). Third, we distinguish blocks with low-bitrate last-hops and show that such blocks are often underutilized.

Citation: Xue Cai and John Heidemann. Understanding Block-level Address Usage in the Visible Internet. In Proceedings of the ACM SIGCOMM Conference , p. to appear. New Delhi, India, ACM. August, 2010. <http://www.isi.edu/~johnh/PAPERS/Cai10a.html>.

The article provides a nice summary of the issues, but it reaches a conclusion that is stronger supported by the study.  The subhead of the article is “A survey shows that addresses are not running out as quickly as we’d thought”, and the article draws the conclusion: “the problem [of IPv4 address exhaustion] may not be as bad as many fear.”

The article’s conclusion, I think, overly simplifies matters—it is only true if the “better things we should be doing in managing the IPv4 address space” are free. The Internet Census we carried out supports the opportunity for better IPv4 address space management.  But an open question is the cost of such management.  Historically, with plentiful IPv4 addresses, IPv4 management costs have been small, but potential better IPv4 management will likely be much more costly.  This cost of ongoing IPv4 management needs to be weighed against the costs of one-time conversion cost to IPv6 coupled followed lower IPv6 management costs.

To me, one exciting conclusion from the Internet Census we carried out is that we now have data that allows us to start evaluating these trade-offs.  The answer may be more careful IPv4 gets us a few years, or that the cost of more careful IPv4 makes IPv6 an obvious choice.  In either case, resolving this transition is important for the Internet community.

A preprint is available at http://www.isi.edu/~johnh/PAPERS/Heidemann08c.html, and an extended version is available as an updated technical report at http://www.isi.edu/~johnh/PAPERS/Heidemann08a.html.

Citation: John Heidemann, Yuri Pradkin, Ramesh Govindan, Christos Papadopoulos, Genevieve Bartlett, and Joseph Bannister. Census and Survey of the Visible Internet. In Proceedings of the ACM Internet Measurement Conference, pp. 169-182. Vouliagmeni, Greece, ACM. October, 2008. http://doi.acm.org/10.1145/1452520.1452542