@inproceedings {42705,
	title = {Coverage and Performance Analysis of 5G Non-Standalone Deployments},
	journal = {Proceedings of the 16th ACM Workshop on Wireless Network Testbeds, Experimental evaluation \& CHaracterization},
	year = {2022},
	pages = {61-68},
	publisher = {ACM},
	abstract = {Fifth Generation (5G) networks are becoming the norm in the global telecommunications industry. In this paper, we present the first large-scale measurement study on commercial 5G Non Standalone (NSA) deployments in a European country. We leverage the collected dataset, which covers two Mobile Network Operators (MNOs) in Rome, Italy, to first, study network deployment and radio cov- erage aspects, and second, explore the performance of two use cases related to enhanced Mobile Broadband (eMBB) and Ultra-Reliable Low Latency Communication (URLLC). Results show that 5G NSA can provide higher downlink throughput and slightly lower latency compared to Fourth Generation (4G) systems. However, performance is infuenced by several factors, including propagation conditions, system configurations, and handover events, ultimately highlighting the need for further system optimization.},
	author = {Kousias, Konstantinos and Rajiullah, Mohammad and Caso, Giuseppe and Alay, {\"O}zg{\"u} and Brunstr{\"o}m, Anna and De Nardis, Luca and Neri, Marco and Ali, Usman and Di Benedetto, Maria-Gabriella}
}
@article {42702,
	title = {Data-Driven Analysis of Outdoor-to-Indoor Propagation for 5G Mid-Band Operational Networks},
	journal = {Future Internet},
	volume = {14},
	year = {2022},
	pages = {239},
	publisher = {Multidisciplinary Digital Publishing Institute},
	abstract = {The successful rollout of fifth-generation (5G) networks requires a full understanding of the behavior of the propagation channel, taking into account the signal formats and the frequencies standardized by the Third Generation Partnership Project (3GPP). In the past, channel characterization for 5G has been addressed mainly based on the measurements performed on dedicated links in experimental setups. This paper presents a state-of-the-art contribution to the characterization of the outdoor-to-indoor radio channel in the 3.5 GHz band, based on experimental data for commercial, deployed 5G networks, collected during a large scale measurement campaign carried out in the city of Rome, Italy. The analysis presented in this work focuses on downlink, outdoor-to-indoor propagation for two operators adopting two different beamforming strategies, single wide-beam and multiple synchronization signal blocks (SSB) based beamforming; it is indeed the first contribution studying the impact of beamforming strategy in real 5G networks. The time and power-related channel characteristics, i.e., mean excess delay and Root Mean Square (RMS) delay spread, path loss, and K-factor are studied for the two operators in multiple measurement locations. The analysis of time and power-related parameters is supported and extended by a correlation analysis between each pair of parameters. The results show that beamforming strategy has a marked impact on propagation. A single wide-beam transmission leads, in fact, to lower RMS delay spread and lower mean excess delay compared to a multiple SSB-based transmission strategy. In addition, the single wide-beam transmission system is characterized by a smaller path loss and a higher K-factor, suggesting that the adoption of a multiple SSB-based transmission strategy may have a negative impact on downlink performance.},
	author = {Ali, Usman and Caso, Giuseppe and De Nardis, Luca and Kousias, Konstantinos and Rajiullah, Mohammad and Alay, {\"O}zg{\"u} and Neri, Marco and Brunstr{\"o}m, Anna and Di Benedetto, Maria-Gabriella}
}
@article {42701,
	title = {Energy-Saving Solutions for Cellular Internet of Things{\textendash}A Survey},
	journal = {IEEE Access},
	volume = {10},
	year = {2022},
	pages = {62073-62096},
	publisher = {IEEE},
	abstract = {The Cellular Internet of Things (CIoT), a new paradigm, paves the way for a large-scale deployment of IoT devices. CIoT promises enhanced coverage and massive deployment of low-cost IoT devices with an expected battery life of up to 10 years. However, such a long battery life can only be achieved provided the CIoT device is configured with energy efficiency in mind. This paper conducts a comprehensive survey on energy-saving solutions in 3GPP-based CIoT networks. In comparison to current studies, the contribution of this paper is the classification and an extensive analysis of existing energy-saving solutions for CIoT, e.g., configuration of particular parameter values and software modifications of transport- or radio-layer protocols, while also stressing key parameters impacting the energy consumption such as the frequency of data reporting, discontinuous reception cycles (DRX), and Radio Resource Control (RRC) timers. In addition, we discuss shortcomings, limitations, and possible opportunities which can be investigated in the future to reduce the energy consumption of CIoT devices.},
	author = {Muhammad Tahir {Abbas} and Grinnemo, Karl-Johan and Eklund, Johan and Alfredsson, Stefan and Rajiullah, Mohammad and Brunstr{\"o}m, Anna and Caso, Giuseppe and Kousias, Konstantinos and Alay, {\"O}zg{\"u}}
}
@inproceedings {42700,
	title = {On the Energy-efficient Use of Discontinuous Reception and Release Assistance in NB-IoT},
	journal = {The IEEE 8th World Forum on Internet of Things (IEEE WFIoT) 2022},
	year = {2022},
	publisher = {IEEE Communications Society},
	abstract = {Cellular Internet of Things (CIoT) is a Low-Power Wide-Area Network (LPWAN) technology. It aims for cheap, low-complexity IoT devices that enable large-scale deployments and wide-area coverage. Moreover, to make large-scale deployments of CIoT devices in remote and hard-to-access locations possible, a long device battery life is one of the main objectives of these devices. To this end, 3GPP has defined several energy-saving mechanisms for CIoT technologies, not least for the Narrow-Band Internet of Things~(NB-IoT) technology, one of the major CIoT technologies. Examples of mechanisms defined include CONNECTED-mode DRX (cDRX), Release Assistance Indicator (RAI), and Power Saving Mode (PSM). This paper considers the impact of the essential energy-saving mechanisms on minimizing the energy consumption of NB-IoT devices, especially the cDRX and RAI mechanisms. The paper uses a purpose-built NB-IoT simulator that has been tested in terms of its built-in energy-saving mechanisms and validated with real-world NB-IoT measurements. The simulated results show that it is possible to save 70\%-90\% in energy consumption by enabling the cDRX and RAI. In fact, the results suggest that battery life of 10\,years is only achievable provided the cDRX, RAI, and PSM energy-saving mechanisms are correctly configured and used.},
	author = {Mohammad Tahir {Abbas} and Eklund, Johan and Brunstr{\"o}m, Anna and Alfredsson, Stefan and Rajiullah, Mohammad and Grinnemo, Karl-Johan and Caso, Giuseppe and Kousias, Konstantinos and Alay, {\"O}zg{\"u}}
}
@inproceedings {42704,
	title = {Implications of handover events in commercial 5G non-standalone deployments in Rome},
	journal = {ACM SIGCOMM Workshop on 5G and Beyond Network Measurements, Modeling, and Use Cases},
	year = {2022},
	pages = {22-27},
	publisher = {ACM},
	abstract = {Fifth Generation (5G) cellular networks are gaining popularity and are soon expected to become the norm in the global telecommunications industry. In this paper, we follow an experimental approach to study key aspects of Handover (HO) events in commercial 5G Non Standalone (NSA) deployments. We collect our dataset by conducting a large-scale measurement campaign in the city of Rome, Italy. With our analysis, we aim to first, empirically evaluate the current HO strategies followed in 5G NSA, and second, to show the impact of HOs on end-user application performance. Our results show an increased number of intra-RAT HOs, i.e., HOs between cells with the same Radio Access Technology (RAT), in situation where signal quality conditions between multiple candidate cells is on par. In addition, we show that inter-RAT HOs, i.e., HOs between cells with different RATs, can be detrimental to the application performance.},
	doi = {10.1145/3538394.3546041},
	url = {https://doi.org/10.1145/3538394.3546041},
	author = {Kousias, Konstantinos and Rajiullah, Mohammad and Caso, Giuseppe and Alay, {\"O}zg{\"u} and Brunstr{\"o}m, Anna and De Nardis, Luca and Neri, Marco and Ali, Usman and Di Benedetto, Maria-Gabriella}
}
@article {42703,
	title = {Large-Scale Dataset for the Analysis of Outdoor-to-Indoor Propagation for 5G Mid-Band Operational Networks},
	journal = {Data},
	volume = {7},
	year = {2022},
	pages = {34},
	publisher = {MDPI},
	abstract = {Understanding radio propagation characteristics and developing channel models is fundamental to building and operating wireless communication systems. Among others uses, channel characterization and modeling can be used for coverage and performance analysis and prediction. Within this context, this paper describes a comprehensive dataset of channel measurements performed to analyze outdoor-to-indoor propagation characteristics in the mid-band spectrum identified for the operation of 5th Generation (5G) cellular systems. Previous efforts to analyze outdoor-to-indoor propagation characteristics in this band were made by using measurements collected on dedicated, mostly single-link setups. Hence, measurements performed on deployed and operational 5G networks still lack in the literature. To fill this gap, this paper presents a dataset of measurements performed over commercial 5G networks. In particular, the dataset includes measurements of channel power delay profiles from two 5G networks in Band n78, i.e., 3.3{\textendash}3.8 GHz. Such measurements were collected at multiple locations in a large office building in the city of Rome, Italy by using the Rohde \& Schwarz (R\&S) TSMA6 network scanner during several weeks in 2020 and 2021. A primary goal of the dataset is to provide an opportunity for researchers to investigate a large set of 5G channel measurements, aiming at analyzing the corresponding propagation characteristics toward the definition and refinement of empirical channel propagation models.},
	author = {Ali, Usman and Caso, Giuseppe and De Nardis, Luca and Kousias, Konstantinos and Rajiullah, Mohammad and Alay, {\"O}zg{\"u} and Neri, Marco and Brunstr{\"o}m, Anna and Di Benedetto, Maria-Gabriella}
}
@inproceedings {27698,
	title = {Open Dataset of Operational Mobile Networks},
	journal = {ACM International Symposium on Mobility Management and Wireless Access (MobiWac)},
	year = {2020},
	publisher = {Association for Computing Machinery},
	address = {New York, NY, USA},
	isbn = {9781450381192},
	author = {ali safari {Khatouni} and trevisan, martino and giardano, d. and Rajiullah, Mohammad and Alfredsson, Stefan and Brunstr{\"o}m, Anna and Midoglu, Cise and Alay, {\"O}zg{\"u}}
}
@inproceedings {26429,
	title = {Web Experience in Operational Mobile Networks: Lessons from Two Million Page Visits},
	journal = {WWW {\textquoteright}19: The World Wide Web Conference},
	year = {2019},
	pages = {1532-1543},
	publisher = {ACM},
	author = {Rajiullah, Mohammad and Lutu, Andra and ali safari {Khatouni} and Fida, Mah-rukh and mellia, marco and Brunstr{\"o}m, Anna and Alay, {\"O}zg{\"u} and Alfredsson, Stefan and Mancuso, Vincenzo}
}
@inproceedings {25621,
	title = {FLEX-MONROE: A Unified Platform for Experiments under Controlled and Operational LTE Settings},
	journal = {11th ACM International Workshop on Wireless Network Testbeds, Experimental Evaluation \& Characterization (WiNTECH2017)},
	year = {2017},
	publisher = {ACM},
	address = {Utah, US},
	abstract = {This paper presents FLEX-MONROE, a unique platform that facilitates achieving a thorough understanding of LTE networks, one that captures the status of current operational MBB networks and that also enables LTE performance improvements by allowing experimentation in an environment with controllable LTE parameters. Using this platform, we propose to investigate how variations in the LTE network parameters infuence the network characteristics, which, in turn, translate to application performance metrics that represent the end-user experience. We argue that the FLEX- MONROE platform is crucial to understand, validate and ultimately improve how current operational MBB networks perform, towards providing guidelines for designing future 5G architectures. Furthermore, understanding the effects of low-level tweaks in network parameters in the LTE infrastructure on the application performance is critical to provide guidelines on how to improve the application performance in the current but also future MBB networks.},
	doi = {10.1145/3131473.3131477},
	author = {Fida, Mah-rukh and Kousias, Konstantinos and Lutu, Andra and Rajiullah, Mohammad and Alay, {\"O}zg{\"u} and Brunstr{\"o}m, Anna and Argyriou, Antonios},
	editor = {Kousias, Konstantinos}
}
@article {19183,
	title = {An Evaluation of Tail Loss Recovery Mechanisms for TCP},
	journal = {SIGCOMM Comput. Commun. Rev.},
	volume = {45},
	year = {2015},
	pages = {5{\textendash}11},
	publisher = {ACM},
	address = {New York, NY, USA},
	abstract = {Interactive applications do not require more bandwidth to go faster. Instead, they require less latency. Unfortunately, the current design of transport protocols such as TCP limits possible latency reductions. In this paper we evaluate and compare different loss recovery enhancements to fight tail loss latency. The two recently proposed mechanisms "RTO Restart" (RTOR) and "Tail Loss Probe" (TLP) as well as a new mechanism that applies the logic of RTOR to the TLP timer management (TLPR) are considered. The results show that the relative performance of RTOR and TLP when tail loss occurs is scenario dependent, but with TLP having potentially larger gains. The TLPR mechanism reaps the benefits of both approaches and in most scenarios it shows the best performance.},
	keywords = {congestion control, latency, packet loss, recovery, tcp},
	issn = {0146-4833},
	doi = {10.1145/2717646.2717648},
	url = {http://doi.acm.org/10.1145/2717646.2717648},
	author = {Rajiullah, Mohammad and Hurtig, Per and Brunstr{\"o}m, Anna and Petlund, Andreas and Welzl, Michael}
}
@misc {23700,
	title = {An Evaluation of Tail Loss Recovery Mechanisms for TCP},
	year = {2015},
	publisher = {ACM},
	address = {New York, NY, USA},
	keywords = {congestion control, latency, packet loss, recovery, tcp},
	doi = {10.1145/2717646.2717648},
	url = {http://doi.acm.org/10.1145/2717646.2717648},
	author = {Rajiullah, Mohammad and Hurtig, Per and Brunstrom, Anna and Petlund, Andreas and Welzl, Michael}
}
@misc {funems-2013-applim-poster,
	title = {Reducing Internet Transport Latency for Thin Streams and Short Flows},
	year = {2013},
	month = {7},
	abstract = {The present Internet limits the performance of applications that need real-time interaction. This is in part because the design of the network has been optimised to boost throughput, maximising efficiency for bulk applications. However, changes in use have resulted in that an increasing number of applications now depend on timely delivery. One of the targets of the RITE project is to reduce internet transport latency in support of such applications. Initial results from the project on how end nodes can be optimized for more timely error recovery are presented in this poster.},
	keywords = {Conference},
	author = {Brunstr{\"o}m, Anna and Petlund, Andreas and Rajiullah, Mohammad}
}
