Maps of the interconnections between pairs of networks or Autonomous Systems (ASes), such as Internet providers, are important to a wide range of parties, such as network researchers and network operators, whose activities depend on an accurate view of the Internet and its interconnections. Systematically mapping these interconnections is known to be a notoriously difficult problem. Here, the term 'mapping' refers to first inferring the presence and type of interconnections (e.g., public vs. private peering) and then geolocating them to the colocation facility where the interconnections are provided and utilized. Recently, the introduction of and growing demand for "virtual private interconnections" (VPIs) has been particularly disruptive for any such mapping efforts. VPIs are a new interconnection service that is offered at newly emerging infrastructures called "cloud exchanges" that some of the major colocation facility providers (e.g., Equinix and CoreSite) have started to operate in their major markets. By offering VPIs, these cloud exchanges enable traditional players (e.g., networks operating with an AS number) as well as non-traditional players (e.g., enterprises that do not own an AS number) to connect to any cloud provider that is present at the exchange, thereby enabling cloud-service-related traffic to bypass the public Internet. Moreover, in contrast to the traditional interconnection options, VPIs can be provisioned in real-time via the use of web-based portals. The ability of a large pool of non-traditional Internet players to establish interconnections in the form of VPIs and the increasingly dynamic nature of this type of interconnection have made the systematic mapping of today's Internet interconnections even more challenging. Not only are the existing techniques for mapping Internet interconnections incapable of detecting VPIs, but even when applied to the traditional types of interconnections, their applicability and accuracy remain largely unknown.

As more networks utilize cloud services, the concurrent use of traditional interconnections and cloud-exchange-provided VPIs is becoming more common and requires a new approach for discovering this 'hybrid' connectivity, studying its dynamics, and providing a first-of-its-kind assessment of the type of 'service-to-service' connectivity that is fueled by the 'cloudification' of today's Internet. The main goal of this research project is to develop such a new approach and design and rigorously evaluate the resulting suite of new techniques and open-source tools for inferring and geolocating interconnections in general, and VPIs at both cloud exchanges and certain IXPs (Internet eXchange Points), in particular. An online portal that offers useful visualization capabilities and provides access to a large archive of geo-aware interconnection maps will be developed as part of this project. The project will also enable other research groups to contribute to this important mapping effort, encourage the cross-validation of results by different research groups, and ultimately produce more accurate maps of the Internet's interconnections that can be expected to offer unique insights into new ways of detecting potential Internet vulnerabilities and performance bottlenecks. The project is complemented by an education and outreach plan that includes (i) the development of a curriculum for a new course and graduate level seminars, (ii) the participation of Masters level and undergraduate students in the proposed work (e.g., measurement, visualization), and (iii) the organization of a K-12 outreach activity where CS students volunteer to teach basic programming concepts to students at local elementary, middle, and high schools as part of after-school programs.

National Science Foundation (NSF)
Division of Computer and Network Systems (CNS)
Standard Grant (Standard)
Application #
Program Officer
Darleen L. Fisher
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Duke University
United States
Zip Code