Using Tuangou to reduce IP transit costs

A majority of ISPs (Internet Service Providers) support connectivity to the entire Internet by transiting their traffic via other providers. Although the transit prices per Mbps decline steadily, the overall transit costs of these ISPs remain high or even increase, due to the traffic growth. The discontent of the ISPs with the high transit costs has yielded notable innovations such as peering, content distribution networks, multicast, and peer-to-peer localization. While the above solutions tackle the problem by reducing the transit traffic, this paper explores a novel approach that reduces the transit costs without altering the traffic. In the proposed CIPT (Cooperative IP Transit), multiple ISPs cooperate to jointly purchase IP (Internet Protocol) transit in bulk. The aggregate transit costs decrease due to the economies-of-scale effect of typical subadditive pricing as well as burstable billing: not all ISPs transit their peak traffic during the same period. To distribute the aggregate savings among the CIPT partners, we propose Shapley-value sharing of the CIPT transit costs. Using public data about IP traffic of 264 ISPs and transit prices, we quantitatively evaluate CIPT and show that significant savings can be achieved, both in relative and absolute terms. We also discuss the organizational embodiment, relationship with transit providers, traffic confidentiality, and other aspects of CIPT

On the latency and routing impacts of remote peering to the Internet

Remote peering (RP) has crucially altered the Internet topology and its economics. In creasingly popular thanks to its lower costs and simplicity, RP has shifted the member base of Internet eXchange Points (IXPs) from strictly local to include ASes located any where in the world. While the popularity of RP is well understood, its implications on Internet routing and performance are not. In this thesis, we perform a comprehensive measurement study of RP in the wild, based on a representative set of IXPs (including some of the largest ones in the world, covering the five continents). We first identify the challenges of inferring remote peering and the limitations of the existing methodologies. Next, we perform active measurements to identify the deployment of remote IXP inter faces and announced prefixes in these IXPs, including a longitudinal analysis to observe RP growth over one and a half years. We use the RP inferences on IXPs to investigate whether RP routes announced at IXPs tend to be preferred over local ones and what are their latency and latency variability impacts when using different interconnection meth ods (remote peering, local peering, and transit) to deliver traffic. Next, we asses the RP latency impact when using a remote connection to international IXPs and reaching prefix destinations announced by their members. We perform measurements leveraging the in frastructure of a large Latin American RP reseller and compare the latency to reach IXP prefixes via RP and four Transit providers. Finally, we glimpse some of the RP impli cations on Internet routing. We evaluate how RP can considerably affect IXP members’ connection stability, potentially introduce routing detours caused by prefix announcement mispractices and be the target of traffic engineering by ASes using BGP communities

On the importance of Internet eXchange Points for today's Internet ecosystem

Internet eXchange Points (IXPs) are generally considered to be the successors of the four Network Access Points that were mandated as part of the decommissioning of the NSFNET in 1994/95 to facilitate the transition from the NSFNET to the "public Internet" as we know it today. While this popular view does not tell the whole story behind the early beginnings of IXPs, what is true is that since around 1994, the number of operational IXPs worldwide has grown to more than 300 (as of May 2013), with the largest IXPs handling daily traffic volumes comparable to those carried by the largest Tier-1 ISPs, but IXPs have never really attracted any attention from the networking research community. At first glance, this lack of interest seems understandable as IXPs have apparently little to do with current "hot" topic areas such as data centers and cloud services or software defined networking (SDN) and mobile communication. However, we argue in this article that, in fact, IXPs are all about data centers and cloud services and even SDN and mobile communication and should be of great interest to networking researchers interested in understanding the current and future Internet ecosystem. To this end, we survey the existing but largely unknown sources of publicly available information about IXPs to describe their basic technical and operational aspects and highlight the critical differences among the various IXPs in the different regions of the world, especially in Europe and North America. More importantly, we illustrate the important role that IXPs play in today's Internet ecosystem and discuss how IXP-driven innovation in Europe is shaping and redefining the Internet marketplace, not only in Europe but increasingly so around the world.Comment: 10 pages, keywords: Internet Exchange Point, Internet Architecture, Peering, Content Deliver

Methods for revealing and reshaping the African Internet Ecosystem as a case study for developing regions: from isolated networks to a connected continent

Mención Internacional en el título de doctorWhile connecting end-users worldwide, the Internet increasingly promotes local development by making challenges much simpler to overcome, regardless of the field in which it is used: governance, economy, education, health, etc. However, African Network Information Centre (AfriNIC), the Regional Internet Registry (RIR) of Africa, is characterized by the lowest Internet penetration: 28.6% as of March 2017 compared to an average of 49.7% worldwide according to the International Telecommunication Union (ITU) estimates [139]. Moreover, end-users experience a poor Quality of Service (QoS) provided at high costs. It is thus of interest to enlarge the Internet footprint in such under-connected regions and determine where the situation can be improved. Along these lines, this doctoral thesis thoroughly inspects, using both active and passive data analysis, the critical aspects of the African Internet ecosystem and outlines the milestones of a methodology that could be adopted for achieving similar purposes in other developing regions. The thesis first presents our efforts to help build measurements infrastructures for alleviating the shortage of a diversified range of Vantage Points (VPs) in the region, as we cannot improve what we can not measure. It then unveils our timely and longitudinal inspection of the African interdomain routing using the enhanced RIPE Atlas measurements infrastructure for filling the lack of knowledge of both IPv4 and IPv6 topologies interconnecting local Internet Service Providers (ISPs). It notably proposes reproducible data analysis techniques suitable for the treatment of any set of similar measurements to infer the behavior of ISPs in the region. The results show a large variety of transit habits, which depend on socio-economic factors such as the language, the currency area, or the geographic location of the country in which the ISP operates. They indicate the prevailing dominance of ISPs based outside Africa for the provision of intracontinental paths, but also shed light on the efforts of stakeholders for traffic localization. Next, the thesis investigates the causes and impacts of congestion in the African IXP substrate, as the prevalence of this endemic phenomenon in local Internet markets may hinder their growth. Towards this end, Ark monitors were deployed at six strategically selected local Internet eXchange Points (IXPs) and used for collecting Time-Sequence Latency Probes (TSLP) measurements during a whole year. The analysis of these datasets reveals no evidence of widespread congestion: only 2.2% of the monitored links experienced noticeable indication of congestion, thus promoting peering. The causes of these events were identified during IXP operator interviews, showing how essential collaboration with stakeholders is to understanding the causes of performance degradations. As part of the Internet Society (ISOC) strategy to allow the Internet community to profile the IXPs of a particular region and monitor their evolution, a route-collector data analyzer was then developed and afterward, it was deployed and tested in AfriNIC. This open source web platform titled the “African” Route-collectors Data Analyzer (ARDA) provides metrics, which picture in real-time the status of interconnection at different levels, using public routing information available at local route-collectors with a peering viewpoint of the Internet. The results highlight that a small proportion of Autonomous System Numbers (ASNs) assigned by AfriNIC (17 %) are peering in the region, a fraction that remained static from April to September 2017 despite the significant growth of IXPs in some countries. They show how ARDA can help detect the impact of a policy on the IXP substrate and help ISPs worldwide identify new interconnection opportunities in Africa, the targeted region. Since broadening the underlying network is not useful without appropriately provisioned services to exploit it, the thesis then delves into the availability and utilization of the web infrastructure serving the continent. Towards this end, a comprehensive measurement methodology is applied to collect data from various sources. A focus on Google reveals that its content infrastructure in Africa is, indeed, expanding; nevertheless, much of its web content is still served from the United States (US) and Europe, although being the most popular content source in many African countries. Further, the same analysis is repeated across top global and regional websites, showing that even top African websites prefer to host their content abroad. Following that, the primary bottlenecks faced by Content Providers (CPs) in the region such as the lack of peering between the networks hosting our probes and poorly configured DNS resolvers are explored to outline proposals for further ISP and CP deployments. Considering the above, an option to enrich connectivity and incentivize CPs to establish a presence in the region is to interconnect ISPs present at isolated IXPs by creating a distributed IXP layout spanning the continent. In this respect, the thesis finally provides a four-step interconnection scheme, which parameterizes socio-economic, geographical, and political factors using public datasets. It demonstrates that this constrained solution doubles the percentage of continental intra-African paths, reduces their length, and drastically decreases the median of their Round Trip Times (RTTs) as well as RTTs to ASes hosting the top 10 global and top 10 regional Alexa websites. We hope that quantitatively demonstrating the benefits of this framework will incentivize ISPs to intensify peering and CPs to increase their presence, for enabling fast, affordable, and available access at the Internet frontier.Programa Oficial de Doctorado en Ingeniería TelemáticaPresidente: David Fernández Cambronero.- Secretario: Alberto García Martínez.- Vocal: Cristel Pelsse

A system for profiling the IXPs in a region and monitoring their growth: spotlight at the internet frontier

This work aims at designing and implementing a system able to profile and help manage the set of Internet eXchange Points (IXPs) in an Internet region. As part of the Internet Society's strategy to help monitor and understand the evolution of IXPs in a particular region, a route-collector data analyzer tool was developed before being deployed and tested in AfriNIC. In fact, traffic localization efforts in the African peering ecosystem would be more sustained, and their efficacy assessed if they were supported by a platform, which evaluates and reports in real time about their impact on the Internet. We, thus, built the “African” Route-collectors Data Analyzer (ARDA), an open source web platform for analyzing publicly available routing information collected since 2005, by local route-collectors. ARDA evaluates predefined metrics that picture the status of the interconnection at local, national, and regional levels. It shows that a small proportion of AfriNIC ASes (roughly 17%) are peering in the region. Through them, 58% of all African networks are visible at one IXP or more. These have been static from April to September 2017, and even February 2018, underlining the need for increased efforts to improve local interconnectivity. We show how ARDA can help detect the impact of policies on the growth of local IXPs or continually provide the community with up-to-date empirical data on the evolution of the IXP substrate. Given its features, this tool will be a helpful compass for stakeholders in the quest for better traffic localization and new interconnection opportunities in the targeted region.This work was partially funded by the Internet Society (ISOC). Support to this work was also provided by IMDEA Networks Institute, the National Science Foundation (NSF) CNS-1414177, and NSF OAC-1724853.We are grateful to Nishal Goburdhan and Dibya Khatiwada for their technical support as well as to The African IXP Association (Af-IX), Packet Clearing House (PCH), and Hisham Ibrahim for their cooperation.Publicad

The Impact of IXPs on the AS-level Topology Structure of the Internet

The AS-level topology of the Internet has been quite a hot research topic in the last few years. However, only a small number of studies have been developed that give a structural interpretation of this graph. Such an interpretation is crucially important in order to test protocols and optimal routing algorithms, to design efficient networks, and for failure detection purposes. Moreover, most research does not highlight the role that IXPs have on the AS-level structure of the Internet, although their role is recognized as fundamental. The initial contribution of this study is an analysis of the most important AS-level topologies that are publicly found on the web and an analysis of the topology obtained when they are merged. We compiled structural information from this topology making considerable use of the k-core decomposition technique to delineate various particular classes of nodes. Next, we associated node properties with a reasonable modus operandi of the ASs on the Internet. The second contribution is a study of the impact that ASs connected to IXPs and BGP connections crossing IXPs have on the AS-level topology. To achieve this, we developed a procedure to gather reliable information related to IXPs and their participants

Reshaping the African Internet: From scattered islands to a connected continent

There is an increasing awareness amongst developing regions on the importance of localizing Internet traffic in the quest for fast, affordable, and available Internet access. In this paper, we focus on Africa, where 37 IXPs are currently interconnecting local ISPs, but mostly at the country level. An option to enrich connectivity on the continent and incentivize content providers to establish presence in the region is to interconnect ISPs present at isolated IXPs by creating a distributed IXP layout spanning the continent. The goal of this paper is to investigate whether such IXP interconnection would be possible, and if successful, to estimate the best-case benefits that could be realized in terms of traffic localization and performance. Our hope is that quantitatively demonstrating the benefits will provide incentives for ISPs to intensify their peering relationships in the region. However, it is challenging to estimate this best-case scenario, due to numerous economic, political, and geographical factors influencing the region. Towards this end, we begin with a thorough analysis of the environment in Africa. We then investigate a naive approach to IXP interconnection, which shows that a theoretically optimal solution would be infeasible in practice due to the prevailing socio-economic conditions in the region. We therefore provide an innovative, realistic four-step interconnection scheme to achieve the distributed IXP layout that considers and parameterizes external socio-economic factors using publicly available datasets. We demonstrate that our constrained solution doubles the percentage of continental intra-African paths, reduces their lengths, and drastically decreases the median of their RTTs as well as RTTs to ASes hosting the top 10 global and top 10 regional Alexa websites. Our approach highlights how, given real-world constraints, a solution requires careful considerations in order to be practically realizable.Rodérick Fanou was partially supported by IMDEA Networks Institute, US NSF grant CNS-1414177, and the project BRADE (P2013/ICE-2958) from the Directorate General of Universities and Research, Board of Education, Madrid Regional Governement. Francisco Valera was partially funded by the European Commission under FP7 project LEONE (FP7-317647). Amogh Dhamdhere was partially funded by US NSF grants CNS-1414177 and CNS-1513847.Publicad

On the latency impact of remote peering

Internet Exchange Points (IXPs) play an essential role in the Internet, providing a fabric for thousands of Autonomous Systems (ASes) to interconnect. Initially designed to keep local traffic local, IXPs now interconnect ASes all over the world, and the premise that IXP routes should be shorter and faster than routes through a transit provider may not be valid anymore. Using BGP views from eight IXPs (three in Brazil, two in the U.S., and one each in London, Amsterdam, and Johannesburg), a transit connection at each of these locations, and latency measurements we collected in May 2021, we compare the latency to reach the same addresses using routes from remote peers, local peers, and transit providers. For four of these IXPs, at least 71.4% of prefixes advertised by remote peers also had a local peering route, BGP generally preferred the remote route due to its shorter AS path, but the local route had lower latency than the remote route in the majority of cases. When a remote route was the only peering route available at an IXP, it had slightly lower latency than a corresponding transit route available outside the IXP for >57.6% of the prefixes for seven of the eight IXPs

ADDRESSING THE ULTIMATE FORM OF CYBERSECURITY CONTROL, A MULTIPLE CASE STUDY FOR THE ‘INTERNET KILL SWITCH’

The Internet has proved its capacity to defy the nation-states’ traditional borders. Facing this circumstance, governments became eager to control its infrastructure, as they did in the past with other forms of communication and they have attempted to shut down the Internet in several occasions. Academics and non-governmental organizations have focused their attention on authoritarian regimes because of the impact of Internet shutdowns on human rights. However, this extreme action of government control has also been part of the debate in non-authoritarian regimes. Thus, this dissertation contributes to the academic debate by analyzing democratic and hybrid regimes, their political discourse and concrete actions to shut down the Internet or to consider doing it. This process starts by questioning the traditional belief that democratic governments, self-defenders of the freedom as a human right, would not consider shutting down the Internet. This dissertation is an exploratory study of the rhetoric and actual factors that enable democratic and hybrid regimes to shut down the Internet or consider doing it as part of their national security strategy. This project started by adopting a definition of what an Internet shutdown is, the government attempt to stop all Internet activity within the borders of its nation-state, also known as Internet Kill Switch . The research design for this project carries an online data collection and a comparative case study to answer the research questions that drive this dissertation. Data collection included reputable sources and a triangulation process for validity purposes. The process of online data collection started by developing an inclusion and exclusion criteria to select the case studies. Using the theoretical framework of the Securitization theory of the Copenhagen School, this study identified the arguments democratic, and hybrid regimes use to justify shutting down the Internet. At the same time, this project determined the audiences they try to address and what they understand as a national security situation. Case studies include three well-consolidated democracies, U.S., U.K. and Australia, and two hybrid regimes, Russia and Venezuela. These nation-states were involved in an Internet shutdown, or their governments considered doing it under different circumstances. To identify the political, legal and technical factors that enable a democratic and hybrid regime to shut down the Internet, this project determined specific variables to analyze. For comparative purposes, this project also incorporated two-young-democracies, Brazil and Mexico, and one hybrid regime, Turkey. These last three governments never shut down the Internet and did not consider doing it. From the comparison between regimes politically similar, this research identified similarities and differences in the factors that enable a government to shut down the Internet. The second contribution comes from a conceptual point of view, by clarifying the differences between terms. In this regard, this study challenges the assimilation of shutting down the entire Internet with censorship episodes as if they were equal practices. Finally, from an academic point of view, this dissertation determined that there are no substantial differences between the rhetoric and political, legal and technical factors that enable democratic and hybrid regimes to shut down the Internet