Archive for the 'Measurement' Category

Unintended consequences of submarine cable deployment on Internet routing

Tuesday, December 15th, 2020 by Roderick Fanou

Figure 1: This picture shows a line of floating buoys that designate the path of the long-awaited SACS (South-Atlantic Cable System). This submarine cable now connects Angola to Brazil (Source: G Massala, https://www.menosfios.com/en/finally-cable-submarine-sacs-arrived-to-brazil/, Feb 2018.)

The network layer of the Internet routes packets regardless of the underlying communication media (Wifi, cellular telephony, satellites, or optical fiber). The underlying physical infrastructure of the Internet includes a mesh of submarine cables, generally shared by network operators who purchase capacity from the cable owners [2,11]. As of late 2020, over 400 submarine cables interconnect continents worldwide and constitute the oceanic backbone of the Internet. Although they carry more than 99% of international traffic, little academic research has occurred to isolate end-to-end performance changes induced by their launch.

In mid-September 2018, Angola Cables (AC, AS37468) activated the SACS cable, the first trans-Atlantic cable traversing the Southern hemisphere [1][A1]. SACS connects Angola in Africa to Brazil in South America. Most assume that the deployment of undersea cables between continents improves Internet performance between the two continents. In our paper, “Unintended consequences: Effects of submarine cable deployment on Internet routing”, we shed empirical light on this hypothesis, by investigating the operational impact of SACS on Internet routing. We presented our results at the Passive and Active Measurement Conference (PAM) 2020, where the work received the best paper award [11,7,8]. We summarize the contributions of our study, including our methodology, data collection and key findings.

[A1]  Note that in the same year, Camtel (CM, AS15964), the incumbent operator of Cameroon, and China Unicom (CH, AS9800) deployed the 5,900km South Atlantic Inter Link (SAIL), which links Fortaleza to Kribi (Cameroon) [17], but this cable was not yet lit as of March 2020.

(more…)

Effects of submarine cables deployment on Internet routing: CAIDA wins Best Paper at PAM 2020!

Tuesday, April 21st, 2020 by Roderick Fanou

Congratulations to Roderick Fanou, Bradley Huffaker, Ricky Mok, and kc claffy, for being awarded Best Paper at the Passive and Active Network Measurement Conference PAM 2020!

The abstract from the paper, “Unintended Consequences: Effects of submarine cables deployment on Internet routing“:

We use traceroute and BGP data from globally distributed Internet measurement infrastructures to study the impact of a noteworthy submarine cable launch connecting Africa to South America. We leverage archived data from RIPE Atlas and CAIDA Ark platforms, as well as custom measurements from strategic vantage points, to quantify the differences in end-to-end latency and path lengths before and after deployment of this new South-Atlantic cable. We find that ASes operating in South America significantly benefit from this new cable, with reduced latency to all measured African countries. More surprising is that end-to-end latency to/from some regions of the world, including intra-African paths towards Angola, increased after switching to the cable. We track these unintended consequences to suboptimally circuitous IP paths that traveled from Africa to Europe, possibly North America, and South America before traveling back to Africa over the cable. Although some suboptimalities are expected given the lack of peering among neighboring ASes in the developing world, we found two other causes: (i) problematic intra-domain routing within a single Angolese network, and (ii) suboptimal routing/traffic engineering by its BGP neighbors. After notifying the operating AS of our results, we found that most of these suboptimalities were subsequently resolved. We designed our method to generalize to the study of other cable deployments or outages and share our code to promote reproducibility and extension of our work

The study presents a reproducible method to investigate the impact of a cable deployment on the macroscopic Internet topology and end-to-end performance. We then applied our methodology to the case of SACS (South-Atlantic Cable System), the first South-Atlantic cable from South America to Africa, using historical traceroutes from both Archipelago (Ark) and RIPE Atlas measurement platforms, BGP data, etc.

Boxplots of minimum RTTs from Ark and Atlas Vantage Points to the common IP hops closest to the destination IPs. Sets BEFORE and AFTER correspond to periods pre and post-SACS deployment. We present ∆RTT (AFTER minus BEFORE) per sub-figure. RTT changes are similar across measurement platforms. Paths from South America experienced a median RTT decrease of 38%, those from Oceania-Australia a smaller decrease of 8%, while those from Africa and North America, roughly 3%. Conversely, paths from Europe and Asia that crossed SACS after its deployment experienced an average RTT increase of 40% and 9%, respectively.

As shown in the above figure, our findings included:

  • the median RTT decrease from Africa to Brazil was roughly a third of that from South America to Angola
  • surprising performance degradations to/from some regions worldwide, e.g., Asia and Europe.

We also offered suggestions for how to avoid suboptimal routing that gives rise to such performance degradations post-activation of cables in the future. They could:

  • Inform their BGP neighbours to allow time for changes
  • Ensure optimal iBGP configs post-activation
  • Use measurements platforms to verify path optimality

To enable reproducibility of this work, we made our tools and publicly accessible on GitHub.

Read the full paper on the CAIDA website or watch the PAM presentation video on YouTube.

CAIDA’s Annual Report for 2018

Tuesday, May 7th, 2019 by kc

The CAIDA annual report summarizes CAIDA’s activities for 2018, in the areas of research, infrastructure, data collection and analysis. Our research projects span Internet topology, routing, security, economics, future Internet architectures, and policy. Our infrastructure, software development, and data sharing activities support measurement-based internet research, both at CAIDA and around the world, with focus on the health and integrity of the global Internet ecosystem. The executive summary is excerpted below:
(more…)

9th Workshop on Internet Economics

Tuesday, January 29th, 2019 by kc

On December 12-13, 2018, CAIDA and the Massachusetts Institute of Technology (MIT) hosted the (invitation-only) 9th interdisciplinary Workshop on Internet Economics (WIE) at the University of California San Diego in La Jolla, CA.

The goal of this workshop series is to provide a forum for researchers, commercial Internet facilities and service providers, technologists, economists, theorists, policy makers, and other stakeholders to empirically inform emerging Internet regulatory and policy debates.

Presenters were asked to write talk abstracts on their presented topics, addressing four questions:

  1. What is the policy goal or fear you’re addressing?
  2. What data is needed to measure progress toward/away from this goal fear?
  3. What methods do you propose (or are) being used to gather such data?
  4. Who/how should such methods be executed, and the data shared, or not shared?

With a specific focus on measurement challenges, the topics we discussed included: analyzing the evolution of the Internet in a layered-platform context to gain new insights; measurement and analysis of economic impacts of new technologies using old tools; security and trustworthiness, reach (universal service) and reachability, sustainability of investment into public Internet infrastructure, as well as infrastructure to measure the public Internet.

Some of the takeaways from the workshop included:
(more…)

CAIDA’s Annual Report for 2017

Tuesday, May 29th, 2018 by kc

The CAIDA annual report summarizes CAIDA’s activities for 2017, in the areas of research, infrastructure, data collection and analysis. Our research projects span Internet topology, routing, security, economics, future Internet architectures, and policy. Our infrastructure, software development, and data sharing activities support measurement-based internet research, both at CAIDA and around the world, with focus on the health and integrity of the global Internet ecosystem. The executive summary is excerpted below:
(more…)

CAIDA’s 2016 Annual Report

Tuesday, May 9th, 2017 by kc

[Executive summary and link below]

The CAIDA annual report summarizes CAIDA’s activities for 2016, in the areas of research, infrastructure, data collection and analysis. Our research projects span Internet topology, routing, security, economics, future Internet architectures, and policy. Our infrastructure, software development, and data sharing activities support measurement-based internet research, both at CAIDA and around the world, with focus on the health and integrity of the global Internet ecosystem. The executive summary is excerpted below:

Mapping the Internet. We continued to expand our topology mapping capabilities using our Ark measurement infrastructure. We improved the accuracy and sophistication of our topology annotations, including classification of ISPs, business relationships between them, and geographic mapping of interdomain links that implement these relationships. We released two Internet Topology Data Kits (ITDKs) incorporating these advances.

Mapping Interconnection Connectivity and Congestion. We continued our collaboration with MIT to map the rich mesh of interconnection in the Internet in order to study congestion induced by evolving peering and traffic management practices of CDNs and access ISPs. We focused our efforts on the challenge of detecting and localizing congestion to specific points in between networks. We developed new tools to scale measurements to a much wider set of available nodes. We also implemented a new database and graphing platform to allow us to interactively explore our topology and performance measurements. We produced related data collection and analyses to enable evaluation of these measurements in the larger context of the evolving ecosystem: infrastructure resiliency, economic tussles, and public policy.

Monitoring Global Internet Security and Stability. We conducted infrastructure research and development projects that focus on security and stability aspects of the global Internet. We developed continuous fine-grained monitoring capabilities establishing a baseline connectivity awareness against which to interpret observed changes due to network outages or route hijacks. We released (in beta form) a new operational prototype service that monitors the Internet, in near-real-time, and helps identify macroscopic Internet outages affecting the edge of the network.

CAIDA also developed new client tools for measuring IPv4 and IPv6 spoofing capabilities, along with services that provide reporting and allow users to opt-in or out of sharing the data publicly.

Future Internet Architectures. We continued studies of IPv4 and IPv6 paths in the Internet, including topological congruency, stability, and RTT performance. We examined the state of security policies in IPv6 networks, and collaborated to measure CGN deployment in U.S. broadband networks. We also continued our collaboration with researchers at several other universities to advance development of a new Internet architecture: Named Data Networking (NDN) and published a paper on the policy and social implications of an NDN-based Internet.

Public Policy. Acting as an Independent Measurement Expert, we posted our agreed-upon revised methodology for measurement methods and reporting requirements related to AT&T Inc. and DirecTV merger (MB Docket No. 14-90). We published our proposed method and a companion justification document. Inspired by this experience and a range of contradicting claims about interconnection performance, we introduced a new model describing measurements of interconnection links of access providers, and demonstrated how it can guide sound interpretation of interconnection-related measurements regardless of their source.

Infrastructure operations. It was an unprecedented year for CAIDA from an infrastructure development perspective. We continued support for our existing active and passive measurement infrastructure to provide visibility into global Internet behavior, and associated software tools and platforms that facilitate network research and operational assessments.

We made available several data services that have been years in the making: our prototype Internet Outage Detection and Analysis service, with several underlying components released as open source; the Periscope platform to unify and scale querying of thousands of looking glass nodes on the global Internet; our large-scale Internet topology query system (Henya); and our Spoofer system for measurement and analysis of source address validation across the global Internet. Unfortunately, due to continual network upgrades, we lost access to our 10GB backbone traffic monitoring infrastructure. Now we are considering approaches to acquire new monitors capable of packet capture on 100GB links.

As always, we engaged in a variety of tool development, and outreach activities, including maintaining web sites, publishing 13 peer-reviewed papers, 3 technical reports, 4 workshop reports, one (our first) BGP hackathon report, 31 presentations, 20 blog entries, and hosting 6 workshops (including the hackathon). This report summarizes the status of our activities; details about our research are available in papers, presentations, and interactive resources on our web sites. We also provide listings and links to software tools and data sets shared, and statistics reflecting their usage. Finally, we report on web site usage, personnel, and financial information, to provide the public a better idea of what CAIDA is and does.

For the full 2016 annual report, see http://www.caida.org/home/about/annualreports/2016/

Why IP source address spoofing is a problem and how you can help.

Friday, March 24th, 2017 by Bradley Huffaker

video: http://www.caida.org/publications/animations/security/spoofer-sav-intro
information: Software Systems for Surveying Spoofing Susceptibility
download: https://spoofer.caida.org/

This material is based on research sponsored by the Department of Homeland Security (DHS) Science and Technology Directorate, Homeland Security Advanced Research Projects Agency, Cyber Security Division (DHS S&T/HSARPA/CSD) BAA HSHQDC-14-R-B0005, and the Government of United Kingdom of Great Britain and Northern Ireland via contract number D15PC00188. Views should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of Department of Homeland Security, the U.S. Government, or the Government of United Kingdom of Great Britain and Northern Ireland.

Help save the Internet: Install the new Spoofer client (v1.1.0)!

Sunday, December 18th, 2016 by Josh Polterock

The greatest security vulnerability of the Internet (TCP/IP) architecture is the lack of source address validation, i.e., any sender may put a fake source address in a packet, and the destination-based routing protocols that glue together the global Internet will get that packet to its intended destination. Attackers exploit this vulnerability by sending many (millions of) spoofed-source-address packets to services on the Internet they wish to disrupt (or take offline altogether). Attackers can further leverage intermediate servers to amplify such packets into even larger packets that will cause greater disruption for the same effort on the attacker’s part.

Although the IETF recommended best practices to mitigate this vulnerability by configuring routers to validate that source addresses in packets are legitimate, compliance with such practices (BCP38 and BCP84) are notoriously incentive-incompatible. That is, source address validation (SAV) can be a burden to a network who supports it, but its deployment by definition helps not that network but other networks who are thus protected from spoofed-source attacks from that network. Nonetheless, any network who does not deploy BCP38 is “part of the DDoS problem”.

Over the past several months, CAIDA, in collaboration with Matthew Luckie at the University of Waikato, has upgraded Rob Beverly’s original spoofing measurement system, developing new client tools for measuring IPv4 and IPv6 spoofing capabilities, along with services that provide reporting and allow users to opt-in or out of sharing the data publicly. To find out if your network provider(s), or any network you are visiting, implements filtering and allow IP spoofing, point your web browser at http://spoofer.caida.org/ and install our simple client.

This newly released spoofer v1.1.0 client has implemented parallel probing of targets, providing a 5x increase in speed to complete the test, relative to v.1.0. Among other changes, this new prober uses scamper instead of traceroute when possible, and has improved display of results. The installer for Microsoft Windows now configures Windows Firewall.

For more technical details about the problem of IP spoofing and our approach to measurement, reporting, notifications and remediation, see the slides from Matthew Luckie’s recent slideset, “Software Systems for Surveying Spoofing Susceptibility”, presented to the Australian Network Operators Group (AusNOG) in September 2016.

The project web page reports recently run tests from clients willing to share data publicly, test results classified by Autonomous System (AS) and by country, and a summary statistics of IP spoofing over time. We will enhance these reports over the coming months.

This material is based on research sponsored by the Department of Homeland Security (DHS) Science and Technology Directorate, Homeland Security Advanced Research Projects Agency, Cyber Security Division (DHS S&T/HSARPA/CSD) BAA HSHQDC-14-R-B0005, and the Government of United Kingdom of Great Britain and Northern Ireland via contract number D15PC00188. Views should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of Department of Homeland Security, the U.S. Government, or the Government of United Kingdom of Great Britain and Northern Ireland.

The Remote Peering Jedi

Friday, November 11th, 2016 by Josh Polterock

During the RIPE 73 IXP Tools Hackathon, Vasileios Giotsas, working with collaborators at FORTH/University of Crete, AMS-IX, University College, London, and NFT Consult, created the Remote Peering Jedi Tool to provide a view into the remote peering ecosystem. Given a large and diverse corpus of traceroute data, the tool detects and localizes remote peering at Internet Exchange Points (IXP).

To make informed decisions, researchers and operators desire to know who has remote peering at the various IXPs. For their RIPE hackathon project, the group created a tool to automate the detection using average RTTs from the RIPE Atlas’ massive corpus of traceroute paths. The group collected validation data from boxes inside the three large IXPs to compare to RTTs estimated via Atlas. The data suggests possible opportunities for Content Distribution Networks (CDN) to improve services for smaller IXPs. The project results also offer insights into how to interpret some of the information in PeeringDB. The project further examined how presence-informed RTT geolocation can contribute to identifying the location of resources. These results help reduce the problem space by exploiting the fact that the IP space of a given AS can appear where the AS has presence.

For more details, you can watch Vasileios’ presentation of the Remote Peering Jedi Tool. Or, visit the remote peering portal to see the tool in action.

remote-peering-jedi

NSF WATCH series talk: Mapping Internet Interdomain Congestion

Friday, August 26th, 2016 by kc

Last week I gave a talk at NSF’s 39th Washington Area Trustworthy Computing Hour (WATCH) seminar series on CAIDA’s efforts to map internet interdomain congestion. A recorded webcast of the talk is available.

Abstract:

We used the Ark infrastructure to support an ambitious collaboration with MIT to map the rich mesh of interconnection in the Internet, with a focus on congestion induced by evolving peering and traffic management practices of CDNs and access ISPs, including methods to detect and localize the congestion to specific points in networks. We undertook several studies to pursue two dimensions of this challenge. First, we developed methods and tools to identify interconnection borders, and in some cases their physical locations, from comprehensive Internet topology measurements from many edge vantage points. Then, we developed and deployed scalable performance measurement tools to observe performance at thousands of interconnections, algorithms to mine for evidence of persistent congestion in the resulting data; and a system to visualize the results. We produce other related data collection and analysis to enable evaluation of these measurements in the larger context of the evolving ecosystem: quantifying a given network service providers’ global routing footprint; and business-related classifications of networks. In parallel, we examined the peering ecosystem from an economic perspective, exploring fundamental weaknesses and systemic problems of the currently deployed economic framework of Internet interconnection that will continue to cause peering disputes between ASes.

The slides presented are posted on the CAIDA website: Mapping Internet Interdomain Congestion