Guest editorial: towards enhancing ambient systems, networks and technologies
Venue: J. Ambient Intell. Humaniz. Comput.
Year: 2020

This special issue is based on the best papers selected from the 9th International Conference on Ambient Systems, Networks and Technologies (ANT 2018) which was held in Porto, a Portugal, on 8 11 May 2018. The conference attracted a large number of scientific papers that contributed to the state of the art in the ambient systems, networks and technologies. All the papers selected for this special issue have been extended from their original versions and underwent two rounds of rigorous peer review process. Based on the reviewers' feedback, as well as the evaluations of the Guest Editors, nine papers were selected for this special issue from 14 invited submissions. The accepted papers augment ambient systems by uncovering interesting methodologies related to networks, tracking and sensing technologies, cloud computing, human computer interaction, and agentbased and management models. The first paper by Ahriz et al. is entitled "Performance Evaluations in Optical and Wireless Networks for CONDOR Project" The authors of this paper discussed the importance of network performance that provides services to a great number of users while assuring user's quality of service requirements. The main aim of this paper is to evaluate the wireless and optical networks' performances in terms of link quality, throughput, jitter and delay. The demonstrated results show that a high throughput in optical and wireless networks supports a big load through the launched mobile applications while P2P wireless network connections upset some video applications. The second paper by Petrakis et al. is entitled " This paper proposed a system named iPACS which refers to an automated Physical Access Control System as a cloud service for controlling users' activity, navigation and access in large residential infrastructures, such as apartment buildings and shopping malls. The basic idea of this system is achieved by installing beacon Bluetooth radio transmitters that broadcast their identifier to nearby devices (e.g. users' mobile phones) and then transmit this information safely, together with other application and user data, to a private cloud. The provided services are deployed over secure private clouds capable of dealing safely with sensitive information while ensuring users privacy. The experimental results suggested that the usage capacities and response times of iPACS can be improved significantly by applying certain optimizations on the implementation and deployment of services in the cloud. The third paper by Dias and Grilo is entitled "Multi Hop LoRaWAN Uplink Extension: Specification and Prototype Implementation" This paper presented the design and implementation of a multi hop uplink solution compatible with the LoRaWAN specification, which can act as an extension to already deployed gateways. The authors showed that the routing protocol is successfully implemented and assessed using a linear and bottleneck topology, where the packet reception rate and throughput are measured. This paper also presents the protocol specification and detailed description of a prototype implementation, as well as experimental performance results. The fourth paper by Poniszewska Maranda et al. is entitled "A Real time Service System in the Cloud" The authors of this paper discussed cloud computing and its services and how it influenced the way the software is built. This paper aimed to examine the benefits of cloud usage to support Ansar Ul Haque Yasar ansar.yasar@uhasselt.be