CRAWDAD kth/campus

Dataset of wireless network measurements at the KTH campuses, collected during 2014-2015. DOI: https://doi.org/10.15783/c7-5r6x-4b46The dataset contains records of authenticated user associations to the wireless network of the KTH Royal Institute of Technology in Stockholm. The dataset also includes scan results and mapping information of Wi-Fi networks, collected by means of war-walking at the university's two largest campuses.date/time of measurement start: 2014-01-01date/time of measurement end: 2015-12-14collection environment: The KTH wireless network provides coverage for buildings on one large and four small campuses located within metropolitan Stockholm area. The campus buildings are for non-residential use, housing classrooms, computer laboratories, libraries, offices, administrative premises, cafeterias and restaurants. Due to the high density of access points (APs) and proximity of campus buildings, most of the outdoor areas are covered as well. At the time of the trace collection (2014-2015) the university had around 18000 active students and employees, most of them accessing the wireless network via smartphones, laptops and other portable devices. The number of active wireless users that connected to the network for a weekday varied between 13000 and 15000.network configuration: The number of deployed APs in the network varied from 934, active during the first month to 965 in the last month, with the maximum number of 985 APs in the middle of the experiment. All APs in the network are Cisco Aironet models. The APs are managed by Cisco 5508 Series Wireless Controllers. The wireless controllers are connected, through the university LAN, to an authentication server, in this case FreeRADIUS (version 2) server, which is responsible for handling wireless users access requests.data collection methodology: The two tracesets included in the dataset were collected by different acquisition methodologies. The first traceset consists of Eduroam associations, which were pulled from the authentication server deployed in the university network. These associations constitute 95 % of all associations in the wireless network. User association in an Eduroam network requires RADIUS authentication. For keeping record of all authentication events, FreeRADIUS uses a syslog module _linelog_ which reports events in the [F-Ticks format](http://tools.ietf.org/html/draft-johansson-fticks-00). In the case of Eduroam access, these records are logged and reported to the national operator for collecting statistics at national levels. To obtain the second traceset, we developed a simple Android application to record scan results and coverage of all Wi-Fi networks detected while walking at the campus.error: Some APs were relocated during the course of the experiment, but their names were not modified to reflect these movements. This resulted in those relocated APs showing in the association logs with the name corresponding to the last location where the AP was deployed. We made our best efforts to detect all APs that belong in this group, and subsequently re-assigned names to correspond to the correct buildings (and floors where available) where the APs were deployed in the past.limitation: The traceset contains only records of successful associations, lacking the information of session durations e.g., via de-authentication/disassociation events or accounting logs. The second limitation is the inability to infer any information about user devices from their MAC addresses---for instance, the device type from the OUI portion of the MAC address---since the entire addresses were hashed during logging.Tracesetkth/campus/eduroamDataset of association records to the Eduroam network at the KTH campuses, collected during 2014-2015.file: traceset1.zipdescription: The dataset contains records of authenticated user associations to the wireless network of the KTH Royal Institute of Technology in Stockholm.measurement purpose: User Mobility Characterization, Network Performance Analysis, Location-aware Computing, Usage Characterization, Human Behavior Modeling, Localization, Opportunistic Connectivityeduroam_jan2014 Tracejan2014configuration: The traceset was obtained from the FreeRADIUS server logs of user authentication events.format: The traceset comprises 16 CSV files, where each file contains one month of user associations. Each line in a trace file represents a record of a successful authentication event. The format of these records is the following: timestamp, hashed_user_id, ap_idkth/campus/wifi-mappingCoverage of the Wi-Fi networks at the KTH main campus.file: traceset2.zipdescription: This traceset contains information about detected access points, including location information (GPS coordinates) where the Wi-Fi beacons were captured.measurement purpose: User Mobility Characterization, Network Performance Analysis, Location-aware Computing, Usage Characterization, Positioning Systems , Content Distribution Evaluation, Localizationwifi-mapping Tracewifi-mappingconfiguration: The traceset was collected by war-walking across two largest university campuses. During measurement runs, Wi-Fi scans were performed every 10 seconds. The location associated with a scan result corresponds to the estimated GPS coordinates when the scan started.format: The traceset comprises 32 CSV files, corresponding to separate (short) experiments. In a trace file, each line represents a single scan result. The format of a scan result is the following: timestamp_scan_started, timestamp_scan_ended, longitude, latitude, altitude, GPS_location_accuracy, BSSID, AP_MAC_address, wifi_channel,received_signal_strength_indication, capabilities

本数据集为2014年至2015年间于瑞典皇家理工学院（KTH Royal Institute of Technology）校区采集的无线网络测量数据集，DOI：https://doi.org/10.15783/c7-5r6x-4b46。
本数据集包含瑞典斯德哥尔摩的瑞典皇家理工学院无线网络的已认证用户关联记录，同时包含通过无线网络徒步扫描（war-walking）采集的Wi-Fi网络扫描结果与映射信息，覆盖该大学的两个最大校区。
测量开始日期/时间：2014-01-01；测量结束日期/时间：2015-12-14。
采集环境：KTH无线网络覆盖了位于斯德哥尔摩都会区内的1个主校区与4个分校区的楼宇。校区楼宇均为非住宅用途，内设教室、计算机实验室、图书馆、办公室、行政场所、自助餐厅与餐厅。由于接入点（Access Point, AP）密度较高且校区楼宇间距较近，多数户外区域也处于覆盖范围内。在2014-2015年的数据采集期间，该大学约有18000名在校学生与教职员工，其中多数通过智能手机、笔记本电脑及其他便携式设备接入无线网络。工作日期间连接至该网络的活跃无线用户数量介于13000至15000之间。
网络配置：网络中部署的AP数量从首个月的934台波动至最后一个月的965台，实验中期达到峰值985台。网络内所有AP均为思科（Cisco）Aironet系列型号，由思科5508系列无线控制器进行管理。无线控制器通过大学局域网（Local Area Network, LAN）连接至认证服务器，本数据集采用的是FreeRADIUS（版本2）服务器，负责处理无线用户的接入请求。
数据采集方法：本数据集包含两个追踪集，二者采用不同的采集方法获取。第一个追踪集包含教育网漫游（Eduroam）关联记录，该数据从大学网络中的认证服务器提取而来，占该无线网络所有关联记录的95%。Eduroam网络中的用户关联操作需通过远程认证拨号用户服务（Remote Authentication Dial-In User Service, RADIUS）认证。为记录所有认证事件，FreeRADIUS使用了syslog模块`_linelog_`，该模块以[F-Ticks格式](http://tools.ietf.org/html/draft-johansson-fticks-00)上报事件。针对Eduroam接入的记录会被日志记录并上报至国家运营商，用于国家级统计数据的收集。为获取第二个追踪集，我们开发了一款简易的安卓（Android）应用程序，用于记录在校区内行走时检测到的所有无线网络的扫描结果与覆盖信息。
数据异常说明：实验过程中部分AP曾被迁移，但未修改其名称以反映该迁移操作，导致这些迁移后的AP在关联日志中显示的名称对应其最后一次部署的位置。我们已尽最大努力识别出所有此类AP，并随后将其名称重新分配为与AP过去部署的正确楼宇（如有则包含楼层）相对应的名称。
数据集局限性：本追踪集仅包含成功关联的记录，缺少会话时长相关信息——例如无法通过去认证/解除关联事件或计费日志获取该类信息。第二个局限性在于，无法从用户的媒体访问控制地址（Media Access Control Address, MAC）推断其设备信息，例如无法通过MAC地址的组织唯一标识符（Organizationally Unique Identifier, OUI）部分识别设备类型，因为日志记录过程中已对完整的MAC地址进行了哈希处理。

追踪集1：kth/campus/eduroam
本数据集为2014-2015年间于KTH校区采集的Eduroam网络关联记录数据集。
文件：traceset1.zip
描述：本数据集包含瑞典斯德哥尔摩的瑞典皇家理工学院无线网络的已认证用户关联记录。
测量用途：用户移动性特征刻画、网络性能分析、位置感知计算、使用特征刻画、人类行为建模、定位、机会连通性。

eduroam_jan2014 追踪集
配置：本追踪集源自FreeRADIUS服务器的用户认证事件日志。
格式：本追踪集包含16个逗号分隔值（Comma-Separated Values, CSV）文件，每个文件存储一个月的用户关联记录。追踪文件中的每一行代表一次成功的认证事件记录，记录格式如下：时间戳、哈希后的用户ID、AP标识符。

kth/campus/wifi-mapping KTH主校区无线网络覆盖情况数据集。
文件：traceset2.zip
描述：本追踪集包含检测到的接入点信息，包括捕获Wi-Fi信标时的位置信息（GPS坐标）。
测量用途：用户移动性特征刻画、网络性能分析、位置感知计算、使用特征刻画、定位系统、内容分发评估、定位。

wifi-mapping 追踪集
配置：本追踪集通过在大学两个最大校区开展无线网络徒步扫描（war-walking）采集得到。测量过程中，每10秒执行一次Wi-Fi扫描，扫描结果关联的位置为扫描开始时估算得到的GPS坐标。
格式：本追踪集包含32个逗号分隔值（Comma-Separated Values, CSV）文件，对应独立的（短期）实验。追踪文件中的每一行代表单次扫描结果，扫描结果的格式如下：扫描开始时间戳、扫描结束时间戳、经度、纬度、海拔、GPS定位精度、基本服务集标识符（Basic Service Set Identifier, BSSID）、AP_MAC地址、Wi-Fi信道、接收信号强度指示（Received Signal Strength Indication, RSSI）、功能能力。

搜集汇总

背景与挑战

背景概述

该数据集是CRAWDAD项目下的kth/campus数据集，包含2014年至2015年在瑞典皇家理工学院（KTH）校园收集的无线网络测量数据。数据集由两个子集构成：一是eduroam网络的用户认证关联记录，来源于服务器日志；二是通过步行扫描获取的Wi-Fi网络覆盖信息，包括GPS坐标。这些数据主要用于无线网络研究，如用户移动性分析、网络性能评估和定位系统开发。