arXiv subjects

Simon Egger

Publications and source records attributed to Simon Egger.

4 recordsLinked to original sources

arXiv2026

Compensating the Packet Delay Variation for 6G Integrated with IEEE Time-Sensitive Networking

6G is deemed as a key technology to support emerging applications with stringent requirements for highly dependable and timecritical communication. In this paper, we investigate 6G networks integrated with TSN and how to compensate for wireless stochastic behavior which involves a large intrinsic packet delay variation. We evaluate a 6G solution to reduce packet delay variation that is based on de-jittering. For this, we propose to use virtual timeslots for providing the required time-awareness. We discuss the benefits of the proposed solution while evaluating the impact of the timeslot size on the number of schedulable TSN streams.

cs.NI↗

arXiv2025

An (m,k)-firm Elevation Policy for Weakly Hard Real-Time in Converged 5G-TSN Networks

Ongoing standardization efforts in 5G and Time-Sensitive Networking (TSN) aim to provide safety-critical applications with real-time communication. However, 5G-TSN network schedules often rely on idealistic delay models that can jeopardize the validity of their guarantees. This paper presents an $(m,k)$-firm Elevation Policy to uphold a base level of weakly hard real-time guarantees (WHRT). It augments the primary schedule with a dynamic priority-driven scheme to elevate the priority of $m$ out of $k$ consecutive frames if they experience unexpected delays. Our evaluations demonstrate the necessity of WHRT to increase fault-tolerance against 5G delay outliers and to uphold the quality of control within a 5G-TSN networked control system. Still, only a small resource overhead is imposed during epochs where the primary schedule is valid and can serve stronger QoS guarantees. The $(m,k)$-firm Elevation Policy thereby yields a robust but light-weight fallback mechanism to serve applications with dependable guarantees during unstable network conditions.

cs.NI↗

arXiv2024

Predictability of Performance in Communication Networks Under Markovian Dynamics

With the emergence of time-critical applications in modern communication networks, there is a growing demand for proactive network adaptation and quality of service (QoS) prediction. However, a fundamental question remains largely unexplored: how can we quantify and achieve more predictable communication systems in terms of performance? To address this gap, this paper introduces a theoretical framework for defining and analyzing predictability in communication systems, with a focus on the impact of observations for performance forecasting. We establish a mathematical definition of predictability based on the total variation distance between forecast and marginal performance distributions. A system is deemed unpredictable when the forecast distribution, providing the most comprehensive characterization of future states using all accessible information, is indistinguishable from the marginal distribution, which depicts the system's behavior without any observational input. This framework is applied to multi-hop systems under Markovian conditions, with a detailed analysis of Geo/Geo/1 queuing models in both single-hop and multi-hop scenarios. We derive exact and approximate expressions for predictability in these systems, as well as upper bounds based on spectral analysis of the underlying Markov chains. Our results have implications for the design of efficient monitoring and prediction mechanisms in future communication networks aiming to provide deterministic services.

cs.NI↗

arXiv2017

Pendant Capsule Elastometry

We provide a C/C++ software for the shape analysis of deflated elastic capsules in a pendant capsule geometry, which is based on an elastic description of the capsule material as a quasi two-dimensional elastic membrane using shell theory. Pendant capsule elastometry provides a new in-situ and non-contact method for interfacial rheology of elastic capsules. Given an elastic model of the capsule membrane, pendant capsule elastometry determines optimal elastic moduli by fitting numerically generated axisymmetric shapes optimally to an experimental image. For each digitized image of a deflated capsule elastic moduli can be determined, if another image of its undeformed reference shape is provided. Within this paper, we focus on nonlinear Hookean elasticity because of its low computational cost its wide applicability, but also discuss and implement alternative constitutive laws. For Hookean elasticity, Young's surface modulus (or, alternatively, area compression modulus) and Poisson's ratio are determined; for Mooney-Rivlin elasticity, the Rivlin modulus and a dimensionless shape parameter are determined; for neo-Hookean elasticity, only the Rivlin modulus is determined, using a fixed dimensionless shape parameter. Comparing results for different models we find that nonlinear Hookean elasticity is adequate for most capsules. If series of images are available, these moduli can be evaluated as a function of the capsule volume to analyze hysteresis or aging effects depending on the deformation history. An additional wrinkling wavelength measurement allows the user to determine the bending modulus, from which the layer thickness can be derived. We verify the method by analyzing several materials, compare the results to available rheological measurements, and review several applications. We make the software available under the GPL license at github.com/jhegemann/opencapsule.

cond-mat.soft↗