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new conference paper “Anycast in Context: A Tale of Two Systems” at SIGCOMM 2021

We published a new paper “Anycast in Context: A Tale of Two Systems” by Thomas Koch, Ke Li, Calvin Ardi*, Ethan Katz-Bassett, Matt Calder**, and John Heidemann* (of Columbia, where not otherwise indicated, *USC/ISI, and **Microsoft and Columbia) at ACM SIGCOMM 2021.

From the abstract:

Anycast is used to serve content including web pages and DNS, and anycast deployments are growing. However, prior work examining root DNS suggests anycast deployments incur significant inflation, with users often routed to suboptimal sites. We reassess anycast performance, first extending prior analysis on inflation in the root DNS. We show that inflation is very common in root DNS, affecting more than 95% of users. However, we then show root DNS latency hardly matters to users because caching is so effective. These findings lead us to question: is inflation inherent to anycast, or can inflation be limited when it matters? To answer this question, we consider Microsoft’s anycast CDN serving latency-sensitive content. Here, latency matters orders of magnitude more than for root DNS. Perhaps because of this need, only 35% of CDN users experience any inflation, and the amount they experience is smaller than for root DNS. We show that CDN anycast latency has little inflation due to extensive peering and engineering. These results suggest prior claims of anycast inefficiency reflect experiments on a single application rather than anycast’s technical potential, and they demonstrate the importance of context when measuring system performance.

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new workshop report “Overcoming Measurement Barriers to Internet Research” (WOMBIR 2021) in ACM CCR

WOMBIR 2021 was the NSF-sponsored Workshop on Overcoming Measurement Barriers to Internet Research. This workshop was hold in two sessions over several days in January and April 2021, chaired by k.c. claffy, David Clark, Fabian Bustamente, John Heidemann, and Mattijs Monjker. The final report includes contributions from Aaron Schulman and Ellen Zegura as well as all the workshop participants.

From the abstract:

In January and April 2021 we held the Workshop on Overcoming Measurement Barriers to Internet Research (WOMBIR) with the goal of understanding challenges in network and security data set collection and sharing. Most workshop attendees provided white papers describing their perspectives, and many participated in short-talks and discussion in two virtual workshops over five days. That discussion produced consensus around several points. First, many aspects of the Internet are characterized by decreasing visibility of important network properties, which is in tension with the Internet’s role as critical infrastructure. We discussed three specific research areas that illustrate this tension: security, Internet access; and mobile networking. We discussed visibility challenges at all layers of the networking stack, and the challenge of gathering data and validating inferences. Important data sets require longitudinal (long-term, ongoing) data collection and sharing, support for which is more challenging for Internet research than other fields. We discussed why a combination of technical and policy methods are necessary to safeguard privacy when using or sharing measurement data. Workshop participant proposed several opportunities to accelerate progress, some of which require coordination across government, industry, and academia.

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Presentations Publications

new poster “Measuring the Internet during Covid-19 to Evaluate Work-from-Home” at the NSF PREPARE-VO Workshop

Xiao Song presented the poster “Measuring the Internet during Covid-19 to Evaluate Work-from-Home (poster)” at the NSF PREPARE-VO Workshop on 2020-12-15. Xiao describes the poster in our video.

A case study network showing network changes as a result of work-from-home. Here we know ground truth and can see weekly work behavior (the groups of five bumps), followed by changes on the right in March when work-from-home begins.

There was no formal abstract, but this poster presents early results from examining Internet address changes to identify work-from-home resulting from Covid-19.

This work is part of the MINCEQ project, supported as an NSF CISE RAPID, NSF-2028279.

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DNS Internet

APNIC Blog Post on the effects of chromium generated DNS traffic to the root server system

During the summer of 2019, Haoyu Jiang and Wes Hardaker studied the effects of DNS traffic sent to the root serevr system by chromium-based web browsers. The results of this short research effort were posted to the APNIC blog.

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Papers Publications

new paper “Precise Detection of Content Reuse in the Web” to appear in ACM SIGCOMM Computer Communication Review

We have published a new paper “Precise Detection of Content Reuse in the Web” by Calvin Ardi and John Heidemann, in the ACM SIGCOMM Computer Communication Review (Volume 49 Issue 2, April 2019) newsletter.

From the abstract:

With vast amount of content online, it is not surprising that unscrupulous entities “borrow” from the web to provide content for advertisements, link farms, and spam. Our insight is that cryptographic hashing and fingerprinting can efficiently identify content reuse for web-size corpora. We develop two related algorithms, one to automatically discover previously unknown duplicate content in the web, and the second to precisely detect copies of discovered or manually identified content. We show that bad neighborhoods, clusters of pages where copied content is frequent, help identify copying in the web. We verify our algorithm and its choices with controlled experiments over three web datasets: Common Crawl (2009/10), GeoCities (1990s–2000s), and a phishing corpus (2014). We show that our use of cryptographic hashing is much more precise than alternatives such as locality-sensitive hashing, avoiding the thousands of false-positives that would otherwise occur. We apply our approach in three systems: discovering and detecting duplicated content in the web, searching explicitly for copies of Wikipedia in the web, and detecting phishing sites in a web browser. We show that general copying in the web is often benign (for example, templates), but 6–11% are commercial or possibly commercial. Most copies of Wikipedia (86%) are commercialized (link farming or advertisements). For phishing, we focus on PayPal, detecting 59% of PayPal-phish even without taking on intentional cloaking.

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Presentations

new talk “Verfploeter: Broad and Load-Aware Anycast Mapping”

Wes Hardaker gave the talk “Verfploeter: Broad and Load-Aware Anycast Mapping” at DNS-OARC in San Jose, California, USA on September 29, 2017.  Slides are available at on the event page.

From the abstract:

IP anycast provides DNS operators and CDNs with automatic fail-over and reduced latency by breaking the Internet into catchments,each served by a different anycast site. Unfortunately, understanding and predicting changes to catchments as sites are added or removed has been challenging. Current tools such as RIPE Atlas or commercial equivalents map from thousands of vantage points (VPs),but their coverage can be inconsistent around the globe. This paper proposes Verfploeter, a new method that maps anycast catchments using active probing. Verfploeter provides around 3.8M virtual VPs, 430 times the 9k physical VPs in RIPE Atlas,providing coverage of the vast majority of networks around the globe. We then add load information from prior service logs to provide calibrated predictions of anycast changes. Verfploeter has been used to evaluate the new anycast for B-Root, and we also report its use of a nine-site anycast testbed. We show that the greater coverage made possible by Verfploeter’s active probing is necessary to see routing differences in regions that have sparse coverage from RIPE Atlas, like South America and China.

 

A video of the talk is available On YouTube.