Lisa Maile, M. Sc.
Short Biography
Lisa Maile works as a research assistant at the Chair of Computer Networks and Communication Systems. She studied computer science at the University of Ulm with a focus on computer networks and IT security and successfully completed her studies in 2018 (M.Sc. with award). During her studies in Ulm, she worked as a student employee on Big Data Analytics. Lisa Maile is currently researching the use of Network Calculus for TimeSensitive Networking as part of her doctorate.
More Information
Survey of Protocol Reverse Engineering Algorithms: Decomposition of Tools for Static Traffic Analysis
In: IEEE Communications Surveys & Tutorials PP (2018), p. 11
ISSN: 1553877X
DOI: 10.1109/COMST.2018.2867544
URL: https://ieeexplore.ieee.org/document/8449079/
BibTeX: Download
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SDNAssisted NetworkBased Mitigation of Slow DDoS Attacks
In: Beyah Raheem, Chang Bing, Li Yingjiu, Zhu Sencun (ed.): SecureComm 2018: Security and Privacy in Communication Networks, Cham: Springer International Publishing, 2018, p. 102121
ISBN: 9783030017040
DOI: 10.1007/9783030017040_6
URL: http://arxiv.org/abs/1804.06750
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SDNAssisted NetworkBased Mitigation of Slow HTTP Attacks
In: KuVS Fachgespräch "Network Softwarization"  From Research to Application 2017
DOI: 10.15496/publikation19543
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Network Calculus for TimeSensitive Networking
(Own Funds)
Term: 20181001  20221001This research project deals with the application of quality of service guarantees in TimeSensitive Networking, in particular using Network Calculus. Realtime systems are increasingly required in industry, e.g. the automotive, automation or entertainment industries. Classical Ethernet, however, does not guarantee realtime performance, which leads the TimeSensitive Networking Task Group (IEEE 802.1) to develop standards for realtime data transmission over Ethernet networks. These standards are summarized under the term TimeSensitive Networking (TSN). Within the scope of this research project, the application of Network Calculus for TSN is now being investigated. Network Calculus (NC) is a system theory for deterministic performance evaluation. It uses mathematical methods to provide performance guarantees for communication systems. NC can help evaluate TSN's realtime properties, meet required latency limits, and provide insight into the optimal configuration of networks. It also enables buffer sizing and can evaluate existing or new scheduling algorithms. 
Network Calculus and Optimization
(Own Funds)
Term: since 20040301Network calculus (NC) is a system theory for deterministic performanceevaluation. It uses mathematical methods to provide performanceguarantees for communication systems. It can be applied in thedesign phase of future systems as well as the analysis of existingsystems. In realtime systems, the timeliness of events plays animportant role. Therefore, the classical performance evaluation based onstochastic methods that result in (stochastic) expectation values, i.e.mean values, has to be extended by mathematical tools producingguaranteed bounds for worst case scenarios. Network calculus allows toobtain upper bounds for endtoend delays for one nodes or aseries of nodes within a network, upper bounds for the required bufferspace and bounds for the output flow.These analytic performance bounds characterize the worstcase behaviorof traffic flows and allow dimensioning the corresponding systems.
Currently, we study the applicability of NC for multiplexed flows, inparticular when the FIFO property cannot be assumed at the merging ofindividual flows. The aggregation of data flows plays an important rolein modelling the multiplexing scheme. We apply NC for performanceevaluation both of aggregate multiplexing at one node and atconcatenation of aggregated multiple nodes in different scenarios.
We have successfully introduced network calculus methods in thefield of internal automotive communication systems in industrialapplications. Embedded incar networks need to fulfill hardrealtime constraints. While TDMAbased access schemes in FlexRayguarantee that certain bound can be met, statistical multiplexingin CAN networks only allows to calculate bounds for the highestpriority messages. By applying network calculus, we obtained boundsfor all priority classes without the need to specify a concretescheduling of the messages. Upper bounds for the amount of datathat arrives at each network node are enough to determine hardbounds for the endtoend delay in CAN networks.Another field of application is industrial communication.Factory automation often also requires hard realtime boundsfor the endtoend delay of messages. The use of Ethernet withpriority tagging allows costefficient implementation offactory automation systems. But without stringent planningof the network, the required bounds on the endtoend delaycannot be guaranteed. Network calculus allows to obtain therequired bounds when applied in the planning phase of thenetwork. It also allows to dimension the buffers of nodes,e.g. of industrial Ethernet switches. Nowadays, some ofthe users of industrial Ethernet need to integratenonrealtime products like web cams and remote operationterminals into existing networks. Withoutadditional analysis, the additional traffic caused by devicesthat do not require hard realtime constraints willcause a violation of the bounds for the delay and bufferspace for realtime traffic. By taking into account thisnonrealtime traffic in network calculus and by applyingtraffic shaping for the nonrealtime flows allows todimension the network so that all bounds are met.Network calculus is currently integrated into an existingautomated industrial network planning tool.