Author: xuecai

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Publications Technical Report

New Tech Report “An Organization-Level View of the Internet and its Implications (extended)”

We just published a new technical report “An Organization-Level View of the Internet and its Implications (extended)”, available at ftp://ftp.isi.edu/isi-pubs/tr-679.pdf.
From the abstract:

We present a new clustering approach for mapping ASes to organizations, to develop an organization-level view of the Internet’s AS ecosystem. We demonstrate that the choice of clustering method and use of a new (though unconventional) data source in the form of company subsidiary information contained in the U.S. SEC~Form 10-K filings are both essential to get accurate results. Evaluating our mapping and validating it against carefully chosen datasets shows few (less than 10%) false negatives for 90% of organizations and few false positives for 60% of our organizations. We apply our map to show the importance of an organization-level view of the Internet by contrasting it with the commonly-used view that considers only an organization’s “main” AS. We find that this main-AS view sometimes severely underrepresents the influence of an organization in terms of announced addresses, geographic footprint, and peerings at Internet eXchange Points (IXPs). For example, for 20% of our organizations, the main-AS view detects only 10-60% of the cities covered by the corresponding organization-level view.

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Papers Publications

new conference paper “Towards an AS-to-Organization Map” to appear at IMC

The paper “Towards an AS-to-Organization Map” was accepted by IMC’10 in Melbourne, Australia (available at http://www.isi.edu/~johnh/PAPERS/Cai10c.html).

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.

Categories
Papers Publications

new conference paper “Understanding Block-level Address Usage in the Visible Internet” at SIGCOMM

The paper “Understanding Block-level Address Usage in the Visible Internet” was accepted and presented at SIGCOMM’10 in New Delhi, India (available at http://www.isi.edu/~johnh/PAPERS/Cai10a.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>.

Categories
Publications Technical Report

new tech report “Understanding Address Usage in the Visible Internet”

We just posted a tech report “Understanding Address Usage in the Visible Internet” at <ftp://ftp.isi.edu/isi-pubs/tr-656.pdf>.

The abstract summarizes the tech report:

Although the Internet is widely used today, there are few sound estimates of network demographics. Decentralized network management means questions about Internet use cannot be answered by a central authority, and firewalls and sensitivity to probing means that active measurements must be done carefully and validated against known data. Building on frequent ICMP probing of 1% of the Internet address space, we develop a clustering algorithm 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, the nearing full allocation of IPv4 addresses makes it increasingly important to estimate the costs of better management of the IPv4 space as a component of an IPv6 transition. We provide about how effectively network addresses blocks appear to be used, finding that a significant number of blocks are only lightly used (about one-fifth of /24 blocks ha
ve most addresses in use less than 10% of the time). 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 recently to the Internet (more than 80% in China, while less then 30% in the U.S.).

Xue Cai and John Heidemann. Understanding Address Usage in the Visible Internet. Technical Report N. ISI-TR-2009-656, USC/Information Sciences Institute, February, 2009. http://www.isi.edu/~johnh/PAPERS/Cai09b.html