rement tools and platforms are available. This section gives several QoS measurement tools and platforms; however, such a list is not exhaustive. Some QoS measurement tools include the following: Network diagnostic tool (NDT). This is a Web-based client/server program (based on M-lab measurement platform) that provides measurement of download and upload speed, RTT delay, as well as jitter (including minimum, maximum, and average values from the consecutive measurements) [26]. Besides NDT there are other measurement tools available on the M-lab platform. SpeedTest tool by OOKLA. Similar to NDT this measures RTT time, downlink and uplink speeds, and it is claimed to be used by the most ISPs and users globally [27]. It also offers commercial a measurement solution to ISPs (based on the SpeedTest technology), with customizable broadband performance measurement tools. All QoS measurement tools are based on accompanying measurement platforms, which provide the required client-server infrastructure needed for active measure- ments. Such platforms may provide a pre-defined set of measurement tools or offer an open infrastructure where any measurement tool may be implemented. The tools used can be either hardware or software based. Some of the most popular measurement platforms for performing broadband Internet measurements include the following: Measurement Lab (M-Lab). This is an open, distributed server platform which aims to provide Internet measurement tools developed by different parties [28]. M-lab is not a complete measurement platform by itself, but it provides the necessary infrastruc- ture to set up a measurement platform by deploying QoS measurement tools over the platform. However, the measurement data collected by such tools is made available in the public domain on the basis of an open data approach. 7 Broadband QoS Parameters, KPIs, and Measurements RIPE Atlas. This is the Internet data collection system of the main RIPE Network Coordination Centre (NCC) [29], where RIPE is one of the five regional Interne