@techreport{AlfredssonKasslerVestinetal.2022,
  type      = {Working Paper},
  author    = {Alfredsson, Rebecka and Kassler, Andreas and Vestin, Jonathan and Pieska, Marcus and Amend, Markus},
  title     = {Accelerating a Transport Layer based 5G Multi-Access Proxy on SmartNIC},
  series = {W{\"u}rzburg Workshop on Next-Generation Communication Networks (WueWoWas'22)},
  journal   = {W{\"u}rzburg Workshop on Next-Generation Communication Networks (WueWoWas'22)},
  doi       = {10.25972/OPUS-28079},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-280798},
  pages     = {4},
  year      = {2022},
  abstract  = {Utilizing multiple access technologies such as 5G, 4G, and Wi-Fi within a coherent framework is currently standardized by 3GPP within 5G ATSSS. Indeed, distributing packets over multiple networks can lead to increased robustness, resiliency and capacity. A key part of such a framework is the multi-access proxy, which transparently distributes packets over multiple paths. As the proxy needs to serve thousands of customers, scalability and performance are crucial for operator deployments. In this paper, we leverage recent advancements in data plane programming, implement a multi-access proxy based on the MP-DCCP tunneling approach in P4 and hardware accelerate it by deploying the pipeline on a smartNIC. This is challenging due to the complex scheduling and congestion control operations involved. We present our pipeline and data structures design for congestion control and packet scheduling state management. Initial measurements in our testbed show that packet latency is in the range of 25 μs demonstrating the feasibility of our approach.},
  subject      = {Datennetz},
  language  = {en}
}
@techreport{BrischKasslerVestinetal.2023,
  type      = {Working Paper},
  author    = {Brisch, Fabian and Kassler, Andreas and Vestin, Jonathan and Pieska, Marcus and Amend, Markus},
  title     = {Accelerating Transport Layer Multipath Packet Scheduling for 5G-ATSSS},
  series = {KuVS Fachgespr{\"a}ch - W{\"u}rzburg Workshop on Modeling, Analysis and Simulation of Next-Generation Communication Networks 2023 (WueWoWAS'23)},
  journal   = {KuVS Fachgespr{\"a}ch - W{\"u}rzburg Workshop on Modeling, Analysis and Simulation of Next-Generation Communication Networks 2023 (WueWoWAS'23)},
  doi       = {10.25972/OPUS-32205},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-322052},
  pages     = {4},
  year      = {2023},
  abstract  = {Utilizing multiple access networks such as 5G, 4G, and Wi-Fi simultaneously can lead to increased robustness, resiliency, and capacity for mobile users. However, transparently implementing packet distribution over multiple paths within the core of the network faces multiple challenges including scalability to a large number of customers, low latency, and high-capacity packet processing requirements. In this paper, we offload congestion-aware multipath packet scheduling to a smartNIC. However, such hardware acceleration faces multiple challenges due to programming language and platform limitations. We implement different multipath schedulers in P4 with different complexity in order to cope with dynamically changing path capacities. Using testbed measurements, we show that our CMon scheduler, which monitors path congestion in the data plane and dynamically adjusts scheduling weights for the different paths based on path state information, can process more than 3.5 Mpps packets 25 μs latency.},
  language  = {en}
}
@inproceedings{DaviesDewellHarvey2021,
  author    = {Davies, Richard and Dewell, Nathan and Harvey, Carlo},
  title     = {A framework for interactive, autonomous and semantic dialogue generation in games},
  series = {Proceedings of the 1st Games Technology Summit},
  booktitle = {Proceedings of the 1st Games Technology Summit},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-246023},
  pages     = {16-28},
  year      = {2021},
  abstract  = {Immersive virtual environments provide users with the opportunity to escape from the real world, but scripted dialogues can disrupt the presence within the world the user is trying to escape within. Both Non-Playable Character (NPC) to Player and NPC to NPC dialogue can be non-natural and the reliance on responding with pre-defined dialogue does not always meet the players emotional expectations or provide responses appropriate to the given context or world states. This paper investigates the application of Artificial Intelligence (AI) and Natural Language Processing to generate dynamic human-like responses within a themed virtual world. Each thematic has been analysed against humangenerated responses for the same seed and demonstrates invariance of rating across a range of model sizes, but shows an effect of theme and the size of the corpus used for fine-tuning the context for the game world.},
  language  = {en}
}
@techreport{DeutschmannHielscherGerman2022,
  type      = {Working Paper},
  author    = {Deutschmann, J{\"o}rg and Hielscher, Kai-Steffen and German, Reinhard},
  title     = {Next-Generation Satellite Communication Networks},
  series = {W{\"u}rzburg Workshop on Next-Generation Communication Networks (WueWoWas'22)},
  journal   = {W{\"u}rzburg Workshop on Next-Generation Communication Networks (WueWoWas'22)},
  doi       = {10.25972/OPUS-28073},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-280732},
  pages     = {4},
  year      = {2022},
  abstract  = {This paper gives an overview of our recent activities in the field of satellite communication networks, including an introduction to geostationary satellite systems and Low Earth Orbit megaconstellations. To mitigate the high latencies of geostationary satellite networks, TCP-splitting Performance Enhancing Proxies are deployed. However, these cannot be applied in the case of encrypted transport headers as it is the case for VPNs or QUIC. We summarize performance evaluation results from multiple measurement campaigns. In a recently concluded project, multipath communication was used to combine the advantages of very heterogeneous communication paths: low data rate, low latency (e.g., DSL light) and high data rate, high latency (e.g., geostationary satellite).},
  subject      = {Datennetz},
  language  = {en}
}
@techreport{DworzakGrossmannLe2023,
  type      = {Working Paper},
  author    = {Dworzak, Manuel and Großmann, Marcel and Le, Duy Thanh},
  title     = {Federated Learning for Service Placement in Fog and Edge Computing},
  series = {KuVS Fachgespr{\"a}ch - W{\"u}rzburg Workshop on Modeling, Analysis and Simulation of Next-Generation Communication Networks 2023 (WueWoWAS'23)},
  journal   = {KuVS Fachgespr{\"a}ch - W{\"u}rzburg Workshop on Modeling, Analysis and Simulation of Next-Generation Communication Networks 2023 (WueWoWAS'23)},
  doi       = {10.25972/OPUS-32219},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-322193},
  pages     = {4},
  year      = {2023},
  abstract  = {Service orchestration requires enormous attention and is a struggle nowadays. Of course, virtualization provides a base level of abstraction for services to be deployable on a lot of infrastructures. With container virtualization, the trend to migrate applications to a micro-services level in order to be executable in Fog and Edge Computing environments increases manageability and maintenance efforts rapidly. Similarly, network virtualization adds effort to calibrate IP flows for Software-Defined Networks and eventually route it by means of Network Function Virtualization. Nevertheless, there are concepts like MAPE-K to support micro-service distribution in next-generation cloud and network environments. We want to explore, how a service distribution can be improved by adopting machine learning concepts for infrastructure or service changes. Therefore, we show how federated machine learning is integrated into a cloud-to-fog-continuum without burdening single nodes.},
  language  = {en}
}
@techreport{ElsayedRizk2022,
  type      = {Working Paper},
  author    = {Elsayed, Karim and Rizk, Amr},
  title     = {Response Times in Time-to-Live Caching Hierarchies under Random Network Delays},
  series = {W{\"u}rzburg Workshop on Next-Generation Communication Networks (WueWoWas'22)},
  journal   = {W{\"u}rzburg Workshop on Next-Generation Communication Networks (WueWoWas'22)},
  doi       = {10.25972/OPUS-28084},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-280843},
  pages     = {4},
  year      = {2022},
  abstract  = {Time-to-Live (TTL) caches decouple the occupancy of objects in cache through object-specific validity timers. Stateof- the art techniques provide exact methods for the calculation of object-specific hit probabilities given entire cache hierarchies with random inter-cache network delays. The system hit probability is a provider-centric metric as it relates to the origin offload, i.e., the decrease in the number of requests that are served by the content origin server. In this paper we consider a user-centric metric, i.e., the response time, which is shown to be structurally different from the system hit probability. Equipped with the state-of-theart exact modeling technique using Markov-arrival processes we derive expressions for the expected object response time and pave a way for its optimization under network delays.},
  subject      = {Datennetz},
  language  = {en}
}
@inproceedings{EppleeLangbehn2021,
  author    = {Eppl{\´e}e, Rafael and Langbehn, Eike},
  title     = {Overlapping Architecture: Implementation of Impossible Spaces in Virtual Reality Games},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-246045},
  pages     = {37-46},
  year      = {2021},
  abstract  = {Natural walking in virtual reality games is constrained by the physical boundaries defined by the size of the player's tracking space. Impossible spaces, a redirected walking technique, enlarge the virtual environment by creating overlapping architecture and letting multiple locations occupy the same physical space. Within certain thresholds, this is subtle to the player. In this paper, we present our approach to implement such impossible spaces and describe how we handled challenges like objects with simulated physics or precomputed global illumination.},
  language  = {en}
}
@techreport{FundaKonheiserGermanetal.2023,
  type      = {Working Paper},
  author    = {Funda, Christoph and Konheiser, Tobias and German, Reinhard and Hielscher, Kai-Steffen},
  title     = {How to Model and Predict the Scalability of a Hardware-In-The-Loop Test Bench for Data Re-Injection?},
  series = {KuVS Fachgespr{\"a}ch - W{\"u}rzburg Workshop on Modeling, Analysis and Simulation of Next-Generation Communication Networks 2023 (WueWoWAS'23)},
  journal   = {KuVS Fachgespr{\"a}ch - W{\"u}rzburg Workshop on Modeling, Analysis and Simulation of Next-Generation Communication Networks 2023 (WueWoWAS'23)},
  doi       = {10.25972/OPUS-32215},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-322150},
  pages     = {4},
  year      = {2023},
  abstract  = {This paper describes a novel application of an empirical network calculus model based on measurements of a hardware-in-the-loop (HIL) test system. The aim is to predict the performance of a HIL test bench for open-loop re-injection in the context of scalability. HIL test benches are distributed computer systems including software, hardware, and networking devices. They are used to validate complex technical systems, but have not yet been system under study themselves. Our approach is to use measurements from the HIL system to create an empirical model for arrival and service curves. We predict the performance and design the previously unknown parameters of the HIL simulator with network calculus (NC), namely the buffer sizes and the minimum needed pre-buffer time for the playback buffer. We furthermore show, that it is possible to estimate the CPU load from arrival and service-curves based on the utilization theorem, and hence estimate the scalability of the HIL system in the context of the number of sensor streams.},
  language  = {en}
}
@techreport{FundaMarinGarciaGermanetal.2023,
  type      = {Working Paper},
  author    = {Funda, Christoph and Mar{\´i}n Garc{\´i}a, Pablo and German, Reinhard and Hielscher, Kai-Steffen},
  title     = {Online Algorithm for Arrival \& Service Curve Estimation},
  series = {KuVS Fachgespr{\"a}ch - W{\"u}rzburg Workshop on Modeling, Analysis and Simulation of Next-Generation Communication Networks 2023 (WueWoWAS'23)},
  journal   = {KuVS Fachgespr{\"a}ch - W{\"u}rzburg Workshop on Modeling, Analysis and Simulation of Next-Generation Communication Networks 2023 (WueWoWAS'23)},
  doi       = {10.25972/OPUS-32211},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-322112},
  pages     = {5},
  year      = {2023},
  abstract  = {This paper presents a novel concept to extend state-of-the-art buffer monitoring with additional measures to estimate service-curves. The online algorithm for service-curve estimation replaces the state-of-the-art timestamp logging, as we expect it to overcome the main disadvantages of generating a huge amount of data and using a lot of CPU resources to store the data to a file during operation. We prove the accuracy of the online-algorithm offline with timestamp data and compare the derived bounds to the measured delay and backlog. We also do a proof-of- concept of the online-algorithm, implement it in LabVIEW and compare its performance to the timestamp logging by CPU load and data-size of the log-file. However, the implementation is still work-in-progress.},
  language  = {en}
}
@techreport{GallenmuellerScholzStubbeetal.2022,
  type      = {Working Paper},
  author    = {Gallenm{\"u}ller, Sebastian and Scholz, Dominik and Stubbe, Henning and Hauser, Eric and Carle, Georg},
  title     = {Reproducible by Design: Network Experiments with pos},
  series = {W{\"u}rzburg Workshop on Next-Generation Communication Networks (WueWoWas'22)},
  journal   = {W{\"u}rzburg Workshop on Next-Generation Communication Networks (WueWoWas'22)},
  doi       = {10.25972/OPUS-28083},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-280834},
  pages     = {4},
  year      = {2022},
  abstract  = {In scientific research, the independent reproduction of experiments is the source of trust. Detailed documentation is required to enable experiment reproduction. Reproducibility awards were created to honor the increased documentation effort. In this work, we propose a novel approach toward reproducible research—a structured experimental workflow that allows the creation of reproducible experiments without requiring additional efforts of the researcher. Moreover, we present our own testbed and toolchain, namely, plain orchestrating service (pos), which enables the creation of such experimental workflows. The experiment is documented by our proposed, fully scripted experiment structure. In addition, pos provides scripts enabling the automation of the bundling and release of all experimental artifacts. We provide an interactive environment where pos experiments can be executed and reproduced, available at https://gallenmu.github.io/single-server-experiment.},
  subject      = {Datennetz},
  language  = {en}
}