A Study on PoP Level Mapping

Transcription

1 A Study on PoP Level Mapping

2 Outline qnetwork Mapping qevaluation of Internet qthe reasons for Mapping Internet qinternet Mapping Levels qrelated Works qconclusion

3 Network Mapping

4 ARPANET 1969

5 ARPANET By the end of 1973 there were 37 sites on the ARPANET In June, 1974, there were 62 computers connected to the ARPANET In March, 1977, there were 111 computers on the ARPANET.

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9 INTERNET Connectivity

10 Internet Service Providers q ISPs are organizations that provide services for accessing and using the Internet. qbusiness relationships between ISPs. qisp topologies are private information. qminimal public information which attracts researchers to work on topologies.

11 Why to Map INTERNET qthe big picture of Internet is very crucial to make improvements. qmapping Internet lets researchers to work on real data. qdeveloping optimal routing algorithms, testing on internet models created based on Internet topologies. q Error detection analysis, reliability analysis results development on performance, security.

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13 Internet Mapping Levels qthe lowest level is IP level mapping and it contains all devices connected to the network. qheavy data which is hard to scale and analyze. qone level above IP level is router level mapping. qit combines the multiple IP interfaces to a router. It still creates a heavy data to handle.

14 Internet Mapping Levels qthe highest level of mapping is AS level mapping which is used for analyzing the big picture of network. Internet map is generally drawn by using AS level mapping which is easier to handle. In comparison to IP level and router level mapping, AS level mapping loses size information of AS since both a large AS and a small AS are represented as a single node.

15 Internet Mapping Levels qpop level is between AS level and router level. PoP contains a group of service provider routers which generally located at the same physical location. PoP level mapping gives a better data to handle than router level mapping for big network analysis.

16 Related Works qmeasuring ISP Topologies With Rocketfuel; Neil Spring, Ratul Mahajan, David Wetherall, and Thomas Anderson; 2004 qiplane: An Information Plane for Distributed Services; Harsha V. Madhyastha, Tomas Isdal, Michael Piatek, Colin Dixon,Thomas Anderson, Arvind Krishnamurthy, Arun Venkataramani; 2006 qdimes: Let the Internet Measure Itself; Yuval Shavitt, Eran Shir; 2005

17 Rocketfuel qthe first study on PoP level mapping. qprimary tool for determining the Internet topology is traceroute. qtheir technique for PoP level mapping is based on DNS name resolution. By using the DNS names they separated the routers in Internet Service Provider names and cities. They can also separate the backbone routers and access routers. qs1-bb11-nyc-3.0.sprintlink.net is referring to a Sprint backbone router in New York City. qfor the cases with no DNS name and the location information, they used the neighbor router information to distinguish them.

18 iplane qprimary tool for determining the Internet topology is traceroute. qthe iplane project is also providing PoP level mapping that came up with some improvements to the Rocketfuel project. The main difference they have is thinking that DNS name resolution is not enough to distinguish routers. Because some interfaces have no DNS names, and some might be misnamed and that would cause misleading locations to be concluded. qiplane estimates the number of hops on the reverse path back from a router to a vantage point. The assumption is that routers in the same AS and geographically co-located take the same reverse path back to the vantage point from which they were probed, while routers that are not co-located will not display similar reverse path.

19 DIMES qdistributed Internet Measurements and Simulations (DIMES) qdoesn t use DNS names. qdimes maps take an approach based on geolocation databases: it uses the geographic location of each of the IPs included in a PoP, as denoted by at least three geolocation databases and take the median location. qthe algorithm starts by identifying and marking the PoPs whose location is certain. It then discovers PoPs that are located in the same place as the marked PoPs, based on the PoP-level link delay. Following, it attempts to find the optimal location of non-marked PoPs based on the ratio of PoP-link delay to PoP distance from marked PoPs. The algorithm iterates and tries to improve the location of unmarked PoPs using the location of newly marked PoPs.

20 Conclusion qinternet mapping is an important tool for analysis to increase performance, security, reliability of Internet. qpop level mapping is better for large router datasets to work on network topologies. qapplication of PoP level mapping is aimed as a result of this project.

21 References [1] Network Mapping [2] Autonomous Systems (AS) Topology; Bradley Huffaker, CAIDA, WIND 16, March 2016 [3] Internet PoP Level Maps; Yuval Shavitt and Noa Zilberman, School of Electrical Engineering, Tel-Aviv University, Israel [4] Measuring ISP Topologies With Rocketfuel; Neil Spring, Ratul Mahajan, David Wetherall, and Thomas Anderson

22 References [5] Harsha Madhyastha, iplane: An Information Plane for Distributed Services ; Department of Computer Science and Engineering, University of Washington [6] Yuval Shavitt, Eran Shir, DIMES: Let the Internet Measure Itself [7] Hakan Kardes, Mehmet Gunes, Talha Oz, Cheleby: A Subnet-level Internet Topology Mapping System [8] Yuval Shavitt, Noa Zilberman, A Study of Geolocation Databases [9] Geolocation

23 Thank you!