004 Datenverarbeitung; Informatik
Refine
Has Fulltext
- yes (37)
Document Type
- Working Paper (37) (remove)
Language
- English (37)
Keywords
- Datennetz (14)
- P4 (5)
- SDN (4)
- 5G (2)
- Crowdsourcing (2)
- MP-DCCP (2)
- connected mobility applications (2)
- fog computing (2)
- multipath (2)
- multipath scheduling (2)
- network calculus (2)
- satellite communication (2)
- 5G core network (1)
- 5G-ATSSS (1)
- 5GC (1)
- 6G (1)
- ATSSSS (1)
- Add-on-Miss (1)
- Autorotation (1)
- Balloon (1)
- Containerization (1)
- Crowdsensing (1)
- CubeSat (1)
- Dijkstra’s algorithm (1)
- Edge-MEC-Cloud (1)
- FIFO caching strategies (1)
- Internet of Things (1)
- IoT (1)
- JCAS (1)
- Kathará (1)
- LFU (1)
- LRU (1)
- Lightning (1)
- Linux (1)
- LoRa (1)
- LoRaWan (1)
- MTC (1)
- Mars (1)
- Network Emulator (1)
- Network Experiments (1)
- Network Measurements (1)
- P4-INT (1)
- Performance Enhancing Proxies (1)
- QUIC (1)
- QoE (1)
- Quality of Experience (1)
- Quality of Experience (QoE) (1)
- Quality of Service (QoS) (1)
- RRM (1)
- Reproducibility (1)
- SBA (1)
- SDN/NVF (1)
- Sensing-aaS (1)
- TSN (1)
- TTL (1)
- TTL validation of data consistency (1)
- Testbed (1)
- URLLC (1)
- VNF (1)
- VPN (1)
- Venus (1)
- Visualized Kathará (1)
- aerospace (1)
- autonomic orchestration (1)
- autorotation (1)
- computer performance evaluation (1)
- container virtualization (1)
- crowdsourced QoE measurements (1)
- crowdsourced network measurements (1)
- data plane programming (1)
- dataplane programming (1)
- decoding error rate (1)
- delay QoS exponent (1)
- delay bound violation probability (1)
- delay constrained (1)
- descent (1)
- disjoint multi-paths (1)
- docker (1)
- dynamic flow migration (1)
- effective Bandwidth (1)
- emulation (1)
- energy efficiency (1)
- federated learning (1)
- global IPX network (1)
- haptic data (1)
- hardware-in-the-loop simulation (1)
- hardware-in-the-loop streaming system (1)
- hit ratio analysis and simulation (1)
- hybrid access (1)
- landing (1)
- latency (1)
- least cost (1)
- measurements (1)
- multipath communication (1)
- multipath packet scheduling (1)
- networking (1)
- non-terrestrial networks (1)
- orchestration (1)
- packet reception method (1)
- path computation (1)
- performance monitoring (1)
- plain orchestrating service (1)
- pos (1)
- reconfiguration (1)
- rotorcraft (1)
- scalability evaluation (1)
- service-curve estimation (1)
- short block-length (1)
- shortest path routing (1)
- signaling traffic (1)
- software defined network (1)
- state management (1)
- sustainability (1)
- timestamping method (1)
- topology (1)
- transport protocols (1)
- virtual queue (1)
- wheel (1)
Institute
EU-Project number / Contract (GA) number
- 101069547 (1)
Web caches often use a Time-to-live (TTL) limit to validate data consistency with web servers. We study the impact of TTL constraints on the hit ratio of basic strategies in caches of fixed size. We derive analytical results and confirm their accuracy in comparison to simulations. We propose a score-based caching method with awareness of the current TTL per data for improving the hit ratio close to the upper bound.
Cooperative, connected and automated mobility (CCAM) systems depend on a reliable communication to provide their service and more crucially to ensure the safety of users. One way to ensure the reliability of a data transmission is to use multiple transmission technologies in combination with redundant flows. In this paper, we describe a system requiring multipath communication in the context of CCAM. To this end, we introduce a data plane-based scheduler that uses replication and integration modules to provide redundant and transparent multipath communication. We provide an analytical model for the full replication module of the system and give an overview of how and where the data-plane scheduler components can be realized.
The emerging serverless computing may meet Edge Cloud in a beneficial manner as the two offer flexibility and dynamicity in optimizing finite hardware resources. However, the lack of proper study of a joint platform leaves a gap in literature about consumption and performance of such integration. To this end, this paper identifies the key questions and proposes a methodology to answer them.
The Fifth Generation (5G) communication technology, its infrastructure and architecture, though already deployed in campus and small scale networks, is still undergoing continuous changes and research. Especially, in the light of future large scale deployments and industrial use cases, a detailed analysis of the performance and utilization with regard to latency and service times constraints is crucial. To this end, a fine granular investigation of the Network Function (NF) based core system and the duration for all the tasks performed by these services is necessary. This work presents the first steps towards analyzing the signaling traffic in 5G core networks, and introduces a tool to automatically extract sequence diagrams and service times for NF tasks from traffic traces.
Packets sent over a network can either get lost or reach their destination. Protocols like TCP try to solve this problem by resending the lost packets. However, retransmissions consume a lot of time and are cumbersome for the transmission of critical data. Multipath solutions are quite common to address this reliability issue and are available on almost every layer of the ISO/OSI model. We propose a solution based on a P4 network to duplicate packets in order to send them to their destination via multiple routes. The last network hop ensures that only a single copy of the traffic is further forwarded to its destination by adopting a concept similar to Bloom filters. Besides, if fast delivery is requested we provide a P4 prototype, which randomly forwards the packets over different transmission paths. For reproducibility, we implement our approach in a container-based network emulation system called Kathará.
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.
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.
LoRaWAN Network Planning in Smart Environments: Towards Reliability, Scalability, and Cost Reduction
(2022)
The goal in this work is to present a guidance for LoRaWAN planning to improve overall reliability for message transmissions and scalability. At the end, the cost component is discussed. Therefore, a five step approach is presented that helps to plan a LoRaWAN deployment step by step: Based on the device locations, an initial gateway placement is suggested followed by in-depth frequency and channel access planning. After an initial planning phase, updates for channel access and the initial gateway planning is suggested that should also be done periodically during network operation. Since current gateway placement approaches are only studied with random channel access, there is a lot of potential in the cell planning phase. Furthermore, the performance of different channel access approaches is highly related on network load, and thus cell size and sensor density. Last, the influence of different cell planning ideas on expected costs are discussed.
Lightning has fascinated humanity since the beginning of our existence. Different types of lightning like sprites and blue jets were discovered, and many more are theorized. However, it is very likely that these phenomena are not exclusive to our home planet. Venus’s dense and active atmosphere is a place where lightning is to be expected. Missions like Venera, Pioneer, and Galileo have carried instruments to measure electromagnetic activity. These measurements have indeed delivered results. However, these results are not clear. They could be explained by other effects like cosmic rays, plasma noise, or spacecraft noise. Furthermore, these lightning seem different from those we know from our home planet. In order to tackle these issues, a different approach to measurement is proposed. When multiple devices in different spacecraft or locations can measure the same atmospheric discharge, most other explanations become increasingly less likely. Thus, the suggested instrument and method of VELEX incorporates multiple spacecraft. With this approach, the question about the existence of lightning on Venus could be settled.
The first step towards aerial planetary exploration has been made. Ingenuity shows extremely promising results, and new missions are already underway. Rotorcraft are capable of flight. This capability could be utilized to support the last stages of Entry, Descent, and Landing. Thus, mass and complexity could be scaled down.
Autorotation is one method of descent. It describes unpowered descent and landing, typically performed by helicopters in case of an engine failure. MAPLE is suggested to test these procedures and understand autorotation on other planets. In this series of experiments, the Ingenuity helicopter is utilized. Ingenuity would autorotate a ”mid-air-landing” before continuing with normal flight. Ultimately, the collected data shall help to understand autorotation on Mars and its utilization for interplanetary exploration.