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Presentations

new talk “Digging in to Ground Truth in Network Measurements” at the TMA PhD School 2017

John Heidemann gave the talk “Digging in to Ground Truth in Network Measurements” at the TMA PhD School 2017 in Dublin, Ireland on June 19, 2017.  Slides are available at https://www.isi.edu/~johnh/PAPERS/Heidemann17c.pdf.
From the abstract:

New network measurements are great–you can learn about the whole world! But new network measurements are horrible–are you sure you learn about the world, and not about bugs in your code or approach? New scientific approaches must be tested and ultimately calibrated against ground truth. Yet ground truth about the Internet can be quite difficult—often network operators themselves do not know all the details of their network. This talk will explore the role of ground truth in network measurement: getting it when you can, alternatives when it’s imperfect, and what we learn when none is available.

 

This talk builds on research over the last decade with many people, and the slides include some discussion from the TMA PhD school audience.

Travel to the TMA PhD school was supported by ACM, ISI, and the DHS Retro-Future Bridge and Outages project.

Update 2017-07-05: The TMA folks have posted video of this “Ground Truth” talk to YouTube if you want to relive the glory of a warm afternoon in Dublin.

Categories
Publications Technical Report

new technical report “Recursives in the Wild: Engineering Authoritative DNS Servers”

We have released a new technical report “Recursives in the Wild: Engineering Authoritative DNS Servers”, by Moritz Müller and Giovane C. M. Moura and
Ricardo de O. Schmidt and John Heidemann as an ISI technical report ISI-TR-720.

Recursive DNS server selection of authoritatives, per continent. (Figure 8 from [Mueller17a].)
From the abstract:

In Internet Domain Name System (DNS), services operate authoritative name servers that individuals query through recursive resolvers. Operators strive to provide reliability by operating multiple name servers (NS), each on a separate IP address, and by using IP anycast to allow NSes to provide service from many physical locations. To meet their goals of minimizing latency and balancing load across NSes and anycast, operators need to know how recursive resolvers select an NS, and how that interacts with their NS deployments. Prior work has shown some recursives search for low latency, while others pick an NS at random or round robin, but did not examine how prevalent each choice was. This paper provides the first analysis of how recursives select between name servers in the wild, and from that we provide guidance to name server operators to reach their goals. We conclude that all NSes need to be equally strong and therefore we recommend to deploy IP anycast at every single authoritative.

All datasets used in this paper (but one) are available at https://ant.isi.edu/datasets/dns/index.html#recursives .