Tag: utwente

Categories
Publications Technical Report

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

We have released a new technical report “Verfploeter: Broad and Load-Aware Anycast Mapping”,by Wouter B. de Vries, Ricardo de O. Schmidt, Wes Haraker, John Heidemann, Pieter-Tjerk de Boer, and Aiko Pras as an ISI technical report ISI-TR-717.

Verfploeter coverage of B-Root. Circle radiuses are how many /24 blocks in each 2×2 degree region go to B-Root, and colored slices indicate which go to LAX and which to MIA. (Figure 2b from [Vries17a], dataset: SBV-5-15).
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, 430x 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 9-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.

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

 

Categories
Announcements Collaborations Papers

best paper award at PAM 2017

The PAM 2017 best paper award for “Anycast Latency: How Many Sites Are Enough?”

Congratulations to Ricardo de Oliveira Schmidt (U. Twente), John Heidemann (USC/ISI), and Jan Harm Kuipers (U. Twente) for the award of  best paper at the Conference on Passive and Active Measurement (PAM) 2017 to their paper “Anycast Latency: How Many Sites Are Enough?”.

See our prior blog post for more information about the paper and its data, and the U. Twente blog post about the paper and the SIDN Labs blog post about the paper.

Categories
Papers Publications

new conference paper “Anycast Latency: How Many Sites Are Enough?” in PAM 2017

The paper “Anycast Latency: How Many Sites Are Enough?” will appear at PAM 2017, the Conference on Passive and Active Measurement in March 2017 in Sydney, Australia (available at http://www.isi.edu/~johnh/PAPERS/Schmidt17a.pdf)

Update 2017-03-31:  This paper was awarded Best Paper at PAM 2017.

Median RTT (with quartiles as error bars) for countries with at least 5 vantage points for L-Root in 2015. Even more than 100 anycast sites, L still has relatively high latency in some countries in Africa and Asia.

 

 

 

From the abstract:

Anycast is widely used today to provide important services such as DNS and Content Delivery Networks (CDNs). An anycast service uses multiple sites to provide high availability, capacity and redundancy. BGP routing associates users to sites, defining the catchment that each site serves. Although prior work has studied how users associate with anycast services informally, in this paper we examine the key question how many anycast sites are needed to provide good latency, and the worst case latencies that specific deployments see. To answer this question, we first define the optimal performance that is possible, then explore how routing, specific anycast policies, and site location affect performance. We develop a new method capable of determining optimal performance and use it to study four real-world anycast services operated by different organizations: C-, F-, K-, and L-Root, each part of the Root DNS service. We measure their performance from more than 7,900 vantage points (VPs) worldwide using RIPE Atlas. (Given the VPs uneven geographic distribution, we evaluate and control for potential bias.) Our key results show that a few sites can provide performance nearly as good as many, and that geographic location and good connectivity have a far stronger effect on latency than having many sites. We show how often users see the closest anycast site, and how strongly routing policy affects site selection.

This paper is joint work of  Ricardo de Oliveira Schmidt, John Heidemann (USC/ISI), and Jan Harm Kuipers (U. Twente).  Datasets in this paper are derived from RIPE Atlas and are available at http://traces.simpleweb.org/ and at https://ant.isi.edu/datasets/anycast/.

Categories
Papers Publications

new conference paper “Anycast vs. DDoS: Evaluating the November 2015 Root DNS Event” in IMC 2016

The paper “Anycast vs. DDoS: Evaluating the November 2015 Root DNS Event” will appear at ACM Internet Measurement Conference in November 2016 in Santa Monica, California, USA. (available at http://www.isi.edu/~weilan/PAPER/IMC2016camera.pdf)

From the abstract:

RIPE Atlas VPs going to different anycast sites when under stress. Colors indicate different sites, with black showing unsuccessful queries. [Moura16b, figure 11b]

Distributed Denial-of-Service (DDoS) attacks continue to be a major threat in the Internet today. DDoS attacks overwhelm target services with requests or other traffic, causing requests from legitimate users to be shut out. A common defense against DDoS is to replicate the service in multiple physical locations or sites. If all sites announce a common IP address, BGP will associate users around the Internet with a nearby site,defining the catchment of that site. Anycast addresses DDoS both by increasing capacity to the aggregate of many sites, and allowing each catchment to contain attack traffic leaving other sites unaffected. IP anycast is widely used for commercial CDNs and essential infrastructure such as DNS, but there is little evaluation of anycast under stress. This paper provides the first evaluation of several anycast services under stress with public data. Our subject is the Internet’s Root Domain Name Service, made up of 13 independently designed services (“letters”, 11 with IP anycast) running at more than 500 sites. Many of these services were stressed by sustained traffic at 100 times normal load on Nov.30 and Dec.1, 2015. We use public data for most of our analysis to examine how different services respond to the these events. We see how different anycast deployments respond to stress, and identify two policies: sites may absorb attack traffic, containing the damage but reducing service to some users, or they may withdraw routes to shift both good and bad traffic to other sites. We study how these deployments policies result in different levels of service to different users. We also show evidence of collateral damage on other services located near the attacks.

This IMC paper is joint work of  Giovane C. M. Moura, Moritz Müller, Cristian Hesselman (SIDN Labs), Ricardo de O. Schmidt, Wouter B. de Vries (U. Twente), John Heidemann, Lan Wei (USC/ISI). Datasets in this paper are derived from RIPE Atlas and are available at http://traces.simpleweb.org/ and at https://ant.isi.edu/datasets/anycast/.

Categories
Publications Technical Report

new technical report “Anycast vs. DDoS: Evaluating the November 2015 Root DNS Event”

We have released a new technical report “Anycast vs. DDoS: Evaluating the November 2015 Root DNS Event”, ISI-TR-2016-709, available at http://www.isi.edu/~johnh/PAPERS/Moura16a.pdf

From the abstract:

[Moura16a] Figure 3
[Moura16a] Figure 3: reachability at several root letters (anycast instances) during two events with very heavy traffic.

Distributed Denial-of-Service (DDoS) attacks continue to be a major threat in the Internet today. DDoS attacks overwhelm target services with requests or other traffic, causing requests from legitimate users to be shut out. A common defense against DDoS is to replicate the service in multiple physical locations or sites. If all sites announce a common IP address, BGP will associate users around the Internet with a nearby site,defining the catchment of that site. Anycast addresses DDoS both by increasing capacity to the aggregate of many sites, and allowing each catchment to contain attack traffic leaving other sites unaffected. IP anycast is widely used for commercial CDNs and essential infrastructure such as DNS, but there is little evaluation of anycast under stress. This paper provides the first evaluation of several anycast services under stress with public data. Our subject is the Internet’s Root Domain Name Service, made up of 13 independently designed services (“letters”, 11 with IP anycast) running at more than 500 sites. Many of these services were stressed by sustained traffic at 100 times normal load on Nov.30 and Dec.1, 2015. We use public data for most of our analysis to examine how different services respond to the these events. We see how different anycast deployments respond to stress, and identify two policies: sites may absorb attack traffic, containing the damage but reducing service to some users, or they may withdraw routes to shift both good and bad traffic to other sites. We study how these deployments policies result in different levels of service to different users. We also show evidence of collateral damage on other services located near the attacks.

This technical report is joint work of  Giovane C. M. Moura, Moritz Müller, Cristian Hesselman(SIDN Labs), Ricardo de O. Schmidt, Wouter B. de Vries (U. Twente), John Heidemann, Lan Wei (USC/ISI). Datasets in this paper are derived from RIPE Atlas and are available at http://traces.simpleweb.org/ and at https://ant.isi.edu/datasets/.

Categories
Publications Technical Report

new technical report “Anycast Latency: How Many Sites Are Enough?”

We have released a new technical report “Anycast Latency: How Many Sites Are Enough?”, ISI-TR-2016-708, available at http://www.isi.edu/%7ejohnh/PAPERS/Schmidt16a.pdf.

[Schmidt16a] figure 4: distribution of measured latency (solid lines) to optimal possible latency (dashed lines) for 4 Root DNS anycast deployments.
[Schmidt16a] figure 4: distribution of measured latency (solid lines) to optimal possible latency (dashed lines) for 4 Root DNS anycast deployments.
From the abstract:

Anycast is widely used today to provide important services including naming and content, with DNS and Content Delivery Networks (CDNs). An anycast service uses multiple sites to provide high availability, capacity and redundancy, with BGP routing associating users to nearby anycast sites. Routing defines the catchment of the users that each site serves. Although prior work has studied how users associate with anycast services informally, in this paper we examine the key question how many anycast sites are needed to provide good latency, and the worst case latencies that specific deployments see. To answer this question, we must first define the optimal performance that is possible, then explore how routing, specific anycast policies, and site location affect performance. We develop a new method capable of determining optimal performance and use it to study four real-world anycast services operated by different organizations: C-, F-, K-, and L-Root, each part of the Root DNS service. We measure their performance from more than worldwide vantage points (VPs) in RIPE Atlas. (Given the VPs uneven geographic distribution, we evaluate and control for potential bias.) Key results of our study are to show that a few sites can provide performance nearly as good as many, and that geographic location and good connectivity have a far stronger effect on latency than having many nodes. We show how often users see the closest anycast site, and how strongly routing policy affects site selection.

This technical report is joint work of Ricardo de O. Schmidt and Jan Harm Kuipers (U. Twente) and John Heidemann (USC/ISI).  Datasets in this paper are derived from RIPE Atlas and are available at http://traces.simpleweb.org/.