DOI: 10.6084/m9.figshare.23566146.v1
title: Change Point Detection in WLANs with Random AP Forests

description: <b>Artifacts from the </b><b>ACM CoNEXT' 23</b><b> paper "Change Point Detection in WLANs with Random AP Forests".</b>Collection environmentThe collection campaign targeted a real 5GHz band WLAN and lasted over two months. The WLAN is a production network with thousands of daily users, located in a single floor of a large building equipped with 33 APs.The telemetry consists of a single AP-level Key Performance Indicator (KPI), collected every minute. In particular, KPI in the dataset is the path loss measurement among pairs of APs and is aggregated in time (at a 15 minutes granularity corresponding to up to 96 samples per day) and space (for each undirected AP pair, a single average value of the pathloss is reported). This information is contained in the <code>rapf_kpis.csv</code> file.A portion of the dataset is further annotated with ground truth concerning 9 relevant events that alter the signals, providing a benchmark to assess the validity of the change point detection. This information is contained in the <code>rapf_labels.csv</code> file.ArtifactsDataset comprises two csv files: <code>rapf_kpis.csv</code> (corresponding to the path loss KPI time series), and <code>rapf_labels.csv</code> (corresponding to the ground truth events).For both datasets, rows correspond to time, while the 529 columns correspond to:the timestamp (column 1),the 528 distinct undirected pairs between the 33 APs, expressed with the format <code>APx--APy</code> (with x &lt; y, as undirected KPIs are reported, for the remaining columns).Time series KPI dataEach measured path loss value is collected for a certain AP pair over a 15 minutes timeframe. During a period of two months (from Dec 02, 2021 to Feb 09, 2022), 2.2 million samples were collected among the 528 AP pairs. Missing values are introduced either by technical problems in the data collection (for 2 days among the 70 collection days), or by the inability for APs to collect path loss measurements of the distant neighbors (roughly 35% of samples are missing in the dataset). The path loss values are expressed in dB and range from 43 to 119 (median and mean of 78). Missing values are expressed as <code>NA</code>. In more details:Collection from 2021-12-02T00:00:00Z to 2022-02-09T23:45:00Z (70 days) following ISO-8601 date representation.In particular, all the timestamps are UTC.Among those 70 days, there are technical problems for two days (2021-12-23, and 2022-02-02) which are not present in the csv.There are 96 timeslots in a day, so the number of rows (without the header) is (70-2)x96 = 6528.Among those 6528 rows, there is one timestamp containing <code>NA</code> for all pairs (2021-12-18T07:30:00Z), while others have all at least one pair that is non missing.Ground truth labelsEach ground truth event contains information regarding the date of occurrence (timestamp) and of the impacted pairs. As ground truth events are scarce, the timestamps that are not present in the <code>rapf_labels.csv</code> do not contain any event for any AP pairs. Overall, <code>rapf_labels.csv </code>contains 9 rows (one per event) and 529 columns (one per each AP pair and timestamp). A cell has either the value of 0 (no change point for this pair at that timestamp) or 1 (a change point occurred at that timestamp for this pair).We provide a succinct description of the nine respective events as follows:<i>Event 1</i>: Dec 06, 2021 at 17:45; all 33 APs impacted.<i>Event 2</i>: Dec 07, 2021 at 16:00; 29 APs impacted (AP15, AP16, AP19, AP24 are not impacted, corresponding to 6 non-impacted AP pairs AP15--AP16, AP15--AP19, AP15--AP24, AP16--AP19, AP16--AP24, AP19--AP24).<i>Event 3</i>: Dec 09, 2021 at 17:30; 1 AP impacted (AP24 is impacted, corresponding to 32 impacted AP pairs).<i>Event 4</i>: Dec 14, 2021 at 16:45; 29 APs impacted (AP10, AP17, AP19, AP28 are not impacted, corresponding to 6 non-impacted AP pairs AP10--AP17, AP10--AP19, AP10--AP28, AP17--AP19, AP17--AP28, AP19--AP28).<i>Event 5</i>: Dec 21, 2021 at 21:30; 29 APs impacted (AP6, AP11, AP19, AP20 are not impacted, corresponding to 6 non-impacted AP pairs AP6--AP11, AP6--AP19, AP6--AP20, AP11--AP19, AP11--AP20, AP19--AP20).<i>Event 6</i>: Jan 04, 2022 at 16:45; all 33 APs impacted.<i>Event 7</i>: Jan 11, 2022 at 18:15; all 33 APs impacted.<i>Event 8</i>: Jan 18, 2022 at 16:30; all 33 APs impacted.<i>Event 9</i>: Feb 04, 2022 at 16:30; all 33 APs impacted.