TY - GEN A1 - Schweissguth, Eike A1 - Parzyjegla, Helge A1 - Danielis, Peter A1 - Mühl, Gero A1 - Timmermann, Dirk A1 - Mehner, Stefan A1 - Hohlfeld, Oliver A1 - Hellmanns, David A1 - Falk, Jonathan T1 - TSN Scheduler Benchmarking T2 - 2023 IEEE 19th International Conference on Factory Communication Systems (WFCS) N2 - Time-Sensitive Networking (TSN) disrupts realtime communication technology by making IEEE Ethernet realtime-capable. For time-triggered, hard realtime traffic, TSN provides standardized mechanisms to reserve communication paths as well as individual transmission time slots for data frames. By leveraging these means in a precomputed network schedule, TSN allows for bounded end-to-end delays and minimal jitter. Not being part of the IEEE standard, corresponding scheduling algorithms are an active field of research. Unfortunately, due to differing model assumptions, evaluation setups, and key metrics, a fair comparison of schedulers is impossible so far. In this paper, we present a systematic and reproducible approach to benchmark TSN schedulers. First, we provide a scheduler taxonomy that enables to cluster schedulers by their characteristics. Second, we analyze interactions of input parameters and scheduler results to derive a benchmarking parcour for quantitative comparisons. Finally, we use the approach to benchmark existing schedulers and show subtle interaction effects. This way, our approach enables—for the first time-comparability between schedulers, fueled by the public availability of our benchmarking scenarios. KW - Schedules KW - Systematics KW - Scheduling algorithms KW - Taxonomy KW - Process control KW - Standardization KW - Benchmark testing Y1 - 2023 UR - https://ieeexplore.ieee.org/document/10144227/authors#full-text-header SN - 978-1-6654-6432-1 SN - 978-1-6654-6433-8 U6 - https://doi.org/10.1109/WFCS57264.2023.10144227 SN - 2835-8414 SN - 2835-8511 PB - IEEE ER - TY - GEN A1 - Doan, Trinh Viet A1 - van Rijswijk-Deij, Roland A1 - Hohlfeld, Oliver A1 - Bajpai, Vaibhav T1 - An Empirical View on Consolidation of the Web T2 - ACM Transactions on Internet Technology (TOIT) N2 - The majority of Web content is delivered by only a few companies that provide Content Delivery Infrastructuress (CDIss) such as Content Delivery Networkss (CDNss) and cloud hosts. Due to increasing concerns about trends of centralization, empirical studies on the extent and implications of resulting Internet consolidation are necessary. Thus, we present an empirical view on consolidation of the Web by leveraging datasets from two different measurement platforms. We first analyze Web consolidation around CDIs at the level of landing webpages, before narrowing down the analysis to a level of embedded page resources. The datasets cover 1(a) longitudinal measurements of DNS records for 166.5 M Web domains over five years, 1(b) measurements of DNS records for Alexa Top 1 M over a month and (2) measurements of page loads and renders for 4.3 M webpages, which include data on 392.3 M requested resources. We then define CDIs penetration as the ratio of CDI-hosted objects to all measured objects, which we use to quantify consolidation around CDIs. We observe that CDI penetration has close to doubled since 2015, reaching a lower bound of 15% for all .com, .net, and .org Web domains as of January 2020. Overall, we find a set of six CDIss to deliver the majority of content across all datasets, with these six CDIss being responsible for more than 80% of all 221.9 M CDI-delivered resources (56.6% of all resources in total). We find high dependencies of Web content on a small group of CDIss, in particular, for fonts, ads, and trackers, as well as JavaScript resources such as jQuery. We further observe CDIss to play important roles in rolling out IPv6 and TLS 1.3 support. Overall, these observations indicate a potential oligopoly, which brings both benefits but also risks to the future of the Web. Y1 - 2022 UR - https://dl.acm.org/doi/full/10.1145/3503158 U6 - https://doi.org/10.1145/3503158 SN - 1557-6051 SN - 1533-5399 VL - 22 IS - 3 SP - 1 EP - 30 ER - TY - GEN A1 - Reelfs, Jens Helge A1 - Hohlfeld, Oliver A1 - Strohmaier, Markus A1 - Henckell, Niklas T1 - Characterizing the country-wide adoption and evolution of the Jodel messaging app in Saudi Arabia T2 - arXiv N2 - Social media is subject to constant growth and evolution, yet little is known about their early phases of adoption. To shed light on this aspect, this paper empirically characterizes the initial and country-wide adoption of a new type of social media in Saudi Arabia that happened in 2017. Unlike established social media, the studied network Jodel is anonymous and location-based to form hundreds of independent communities country-wide whose adoption pattern we compare. We take a detailed and full view from the operators perspective on the temporal and geographical dimension on the evolution of these different communities—from their very first the first months of establishment to saturation. This way, we make the early adoption of a new type of social media visible, a process that is often invisible due to the lack of data covering the first days of a new network. Y1 - 2022 UR - https://arxiv.org/abs/2205.04544 U6 - https://doi.org/10.48550/arXiv.2205.04544 ER - TY - GEN A1 - Bajpai, Vaibhav A1 - Hohlfeld, Oliver A1 - Crowcroft, Jon A1 - Keshav, Srinivasan A1 - Schulzrinne, Henning A1 - Ott, Jörg A1 - Ferlin, Simone A1 - Carle, Georg A1 - Hines, Andrew A1 - Raake, Alexander T1 - Recommendations for Designing Hybrid Conferences T2 - ACM SIGCOMM Computer Communication Review N2 - During the COVID-19 pandemic, many smaller conferences have moved entirely online and larger ones are being held as hybrid events. Even beyond the pandemic, hybrid events reduce the carbon footprint of conference travel and makes events more accessible to parts of the research community that have difficulty traveling long distances, while preserving most advantages of in-person gatherings. While we have developed a solid understanding of how to design virtual events over the last two years, we are still learning how to properly run hybrid events. We present guidelines and considerations-spanning technology, organization and social factors-for organizing successful hybrid conferences. This paper summarizes and extends the discussions held at the Dagstuhl seminar on "Climate Friendly Internet Research" held in July 2021. Y1 - 2022 U6 - https://doi.org/10.1145/3544912.3544920 SN - 0146-4833 SN - 1943-5819 VL - 52 IS - 2 SP - 63 EP - 69 ER - TY - GEN A1 - Wichtlhuber, Matthias A1 - Strehle, Eric A1 - Kopp, Daniel A1 - Prepens, Lars A1 - Stegmueller, Stefan A1 - Rubina, Alina A1 - Dietzel, Christoph A1 - Hohlfeld, Oliver T1 - IXP Scrubber: Learning from Blackholing Traffic for ML-Driven DDoS Detection at Scale T2 - ACM SIGCOMM 2022 Conference, 2022 N2 - Distributed Denial of Service (DDoS) attacks are among the most critical cybersecurity threats, jeopardizing the stability of even the largest networks and services. The existing range of mitigation services predominantly filters at the edge of the Internet, thus creating unnecessary burden for network infrastructures. Consequently, we present IXP Scrubber, a Machine Learning (ML) based system for detecting and filtering DDoS traffic at the core of the Internet at Internet Exchange Points (IXPs) which see large volumes and varieties of DDoS. IXP Scrubber continuously learns DDoS traffic properties from neighboring Autonomous Systems (ASes). It utilizes BGP signals to drop traffic for certain routes (blackholing) to sample DDoS and can thus learn new attack vectors without the operator’s intervention and on unprecedented amounts of training data. We present three major contributions: i) a method to semi-automatically generate arbitrarily large amounts of labeled DDoS training data from IXPs’ sampled packet traces, ii) the novel, controllable, locally explainable and highly precise two-step IXP Scrubber ML model, and iii) an evaluation of the IXP Scrubber ML model, including its temporal and geographical drift, based on data from 5 IXPs covering a time span of up to two years. KW - Machine Learning, Traffic Classification, Denial of Service Y1 - 2022 UR - https://dl.acm.org/doi/pdf/10.1145/3544216.3544268 SP - 707 EP - 722 ER - TY - GEN A1 - Mehner, Stefan A1 - Schuster, Franka A1 - Hohlfeld, Oliver T1 - Lights on Power Plant Control Networks T2 - Passive and Active Measurement : 23rd International Conference, PAM 2022, Virtual Event, March 28–30, 2022, Proceedings N2 - Industrial Control Systems (ICS) are critical systems to our society. Yet they are less studied given their closed nature and often the unavailability of data. While few studies focus on wide-area SCADA systems, e.g., power or gas distribution networks, mission critical networks that control power generation are not yet studied. To address this gap, we perform the first measurement study of Distributed Control System (DCS) by analyzing traces from all network levels from several operational power plants. We show that DCS networks feature a rather rich application mix compared to wide-area SCADA networks and that applications and sites can be fingerprinted with statistical means. While traces from operational power plants are hard to obtain, we analyze to which extent easier to access training facilities can be used as vantage points. Our study aims to shed light on traffic properties of critical industries that were not yet analyzed given the lack of data. Y1 - 2022 SN - 978-3-030-98784-8 SN - 978-3-030-98785-5 U6 - https://doi.org/10.1007/978-3-030-98785-5_21 SN - 0302-9743 SN - 1611-3349 SP - 470 EP - 484 PB - Springer ER - TY - GEN A1 - Reelfs, Jens Helge A1 - Hohlfeld, Oliver A1 - Henckell, Niklas T1 - Geographic Differences in Social Media Interactions Exist Between Western and Middle-East Countries T2 - Passive and Active Measurement Conference 2022 N2 - In this paper, we empirically analyze two examples of a Western (DE) versus Middle-East (SA) Online Social Messaging App. By focusing on the system interactions over time in comparison, we identify inherent differences in user engagement. We take a deep dive and shed light onto differences in user attention shifts and showcase their structural implications to the user experience. Our main findings show that in comparison to the German counterparts, the Saudi communities prefer creating content in longer conversations, while voting more conservative. Y1 - 2022 SN - 978-3-030-98785-5 SN - 978-3-030-98784-8 U6 - https://doi.org/10.1007/978-3-030-98785-5_18 SP - 411 EP - 425 PB - Springer CY - Cham ER - TY - GEN A1 - Reelfs, Jens Helge A1 - Mohaupt, Timon A1 - Sikdar, Sandipan A1 - Strohmaier, Markus A1 - Hohlfeld, Oliver T1 - Interpreting Emoji with Emoji: 🏖️ => ☀️😎🌊 T2 - 5th International Workshop on Emoji Understanding and Applications in Social Media 2022 N2 - We study the extent to which emoji can be used to add interpretability to embeddings of text and emoji. To do so, we extend the POLAR-framework that transforms word embeddings to interpretable counterparts and apply it to word-emoji embeddings trained on four years of messaging data from the Jodel social network. We devise a crowdsourced human judgement experiment to study six usecases, evaluating against words only, what role emoji can play in adding interpretability to word embeddings. That is, we use a revised POLAR approach interpreting words and emoji with words, emoji or both according to human judgement. We find statistically significant trends demonstrating that emoji can be used to interpret other emoji very well. Y1 - 2022 UR - https://aiisc.ai/emoji2022/#section-agenda ER - TY - GEN A1 - Reelfs, Jens Helge A1 - Hohlfeld, Oliver A1 - Henckell, Niklas T1 - Anonymous Hyperlocal Communities: What do they talk about? T2 - 12th International Workshop on Location and the Web (LocWeb'22) N2 - In this paper, we study what users talk about in a plethora of independent hyperlocal and anonymous online communities in a single country: Saudi Arabia (KSA). We base this perspective on performing a content classification of the Jodel network in the KSA. To do so, we first contribute a content classification schema that assesses both the intent (why) and the topic (what) of posts. We use the schema to label 15k randomly sampled posts and further classify the top 1k hashtags. We observe a rich set of benign (yet at times controversial in conservative regimes) intents and topics that dominantly address information requests, entertainment, or dating/flirting. By comparing two large cities (Riyadh and Jeddah), we further show that hyperlocality leads to shifts in topic popularity between local communities. By evaluating votes (content appreciation) and replies (reactions), we show that the communities react differently to different topics; e.g., entertaining posts are much appreciated through votes, receiving the least replies, while beliefs & politics receive similarly few replies but are controversially voted. Y1 - 2022 UR - https://arxiv.org/abs/2203.05657 U6 - https://doi.org/10.48550/arXiv.2203.05657 ER - TY - GEN A1 - Feldmann, Anja A1 - Gasser, Oliver A1 - Lichtblau, Franziska A1 - Pujol, Enric A1 - Poese, Ingmar A1 - Dietzel, Christoph A1 - Wagner, Daniel A1 - Wichtlhuber, Matthias A1 - Tapiador, Juan A1 - Vallina-Rodriguez, Narseo A1 - Hohlfeld, Oliver A1 - Smaragdakis, Georgios T1 - A Year in Lockdown: How the Waves of COVID-19 Impact Internet Traffic T2 - Communications of the ACM Y1 - 2021 U6 - https://doi.org/10.1145/3465212 SN - 1557-7317 VL - 64 IS - 7 ER -