DOI: 10.21227/ff9h-mx08
title: CRAWDAD sapienza/probe-requests

description: Wireless probe requests collected in Rome between February and May 2013.Mobile devices try to automatically switch to WiFi connectivity whenever possible. To facilitate this automatic process, they store the list of the names (SSID) of the networks the user typically connects to and, periodically, these SSIDs are sent in broadcast in the form of Probe Request to search for available networks. The following questions then rise naturally: "What do your smartphone probes say about you?"; "Is it possible to infer meaningful relationships among a group of people just using their smartphones' probes?". To answer all these questions, we organized a campaign of probe collection in Rome (Italy): We targeted a university campus as well as city-wide, national and international events. Our campaign lasted three months, and we managed to collect, using commodity hardware only, ~11 million probes sent by ~160 thousand different devices. The release contains anonymized traces in .pcap format.date/time of measurement start: 2013-02-05date/time of measurement end: 2013-05-03collection environment: In our data collection campaign we targeted the following scenarios: 1) events of national audience (political meetings); 2) events of international audience (Pope's Angelus at St. Peter's Square, Vatican); 3) a Mall; 4) a train station; 5) a university campus; 6) other. The first four were one-shot events lasted from 40 minutes to 6 hours each, and whose data collection was physically carried out by a team of 5 researchers equipped with their laptops. The fifth dataset was obtained through a fixed hardware positioned in a university campus over a continuous period of 6 weeks. The last dataset includes probes collected by the research group in other occasions (e.g. commuting from home to the office).data collection methodology: The data was collected by 5 researchers (equipped with their laptops) using tcpdump and applying the following filter to select only the probe-requests: "tcpdump -i $interface type mgt subtype probe-req -w $outfile". Each file in the tracesets has the following name scheme: "probes-yyyy-mm-dd.pcapX", and traces collected in the same day are numbered progressively, starting from 0 (e.g., probes-2013-02-24.pcap0, probes-2013-02-24.pcap1,...)sanitization: We use scapy to dissect and anonymize all MAC addresses and SSIDs in the dataset. In particular, we first build two sets of all SSIDs, respectively all MACs in the dataset. Both, SSIDs and MACs, are then hashed and sorted. Finally, we replace each SSID and MAC in the traces as follows:- we substitute each SSID with the string SSID_i, where i is the corresponding index in the ordered list of hashes (e.g., SSID_000001, SSID_000002, ..., SSID_140152, for a total of 140152 unique SSIDs).- for each MAC address (xx:xx:xx:yy:yy:yy), we keep the first 3 bytes that identify the OUI vendor code (xx:xx:xx), and we substitute the last 3 bytes with the corresponding index in the ordered list of hashes (e.g., xx:xx:xx:00:00:01, xx:xx:xx:00:00:02, ..., xx:xx:xx:16:43:84 , for a total of 164384 unique MAC addresses).Tracesetsapienza/probe-requests/Politics1Wireless probe requests collected at a political meeting in Rome, Italy.file: Politics1.tar.gz description: This traceset contains 12 pcap traces collected during a political meeting organized on February 22nd in San Giovanni Square, by the M5S (Movimento Cinque Stelle) party.measurement purpose: Social Network Analysis, Human Behavior Modelingsapienza/probe-requests/Politics1 TracePolitics1format: This trace contains 12 pcap files compressed in an unique tar.gz archive.sapienza/probe-requests/Politics2Probe requests collected at a political meeting in Rome, Italy.file: Politics2.tar.gzdescription: This traceset contains 7 pcap traces collected at a meeting organized on March 23rd, by the conservative party PDL (Popolo della Liberta). The meeting was held "Piazza del Popolo", a famous square in the city center.measurement purpose: Social Network Analysis, Human Behavior Modelingsapienza/probe-requests/Politics2 Trace Politics2format: This trace contains 7 pcap files compressed in a unique tar.gz archive. sapienza/probe-requests/Vatican1Probe requests collected in St. Peter's Square during Pope Benedict's Angelus and general audience.file: Vatican1.tar.gzdescription: On February 11th, 2013, Pope Benedict announced his resignation, after 8 years of service as the head of the Catholic Church. This traceset contains 11 pcap traces, collected at his farewell Angelus, on February 24th, and during his last general audience, on February 27th.measurement purpose: Social Network Analysis, Human Behavior Modelingsapienza/probe-requests/Vatican1 TraceVatican1format: This trace contains 11 pcap files compressed in an unique tar.gz archive.sapienza/probe-requests/Vatican2Probe requests collected in St. Peter's Square during Pope Francis' Angelus and general audience.file: Vatican2.tar.gzdescription: This traceset contains 7 pcap traces, collected on March 17th, when the newly elected Pope (Pope Francis), delivered his first Angelus and on March 19th, during his first general audience.measurement purpose: Social Network Analysis, Human Behavior Modelingsapienza/probe-requests/Vatican2 TraceVatican2format: This trace contains 7 pcap files compressed in an unique tar.gz archive.sapienza/probe-requests/UniversityProbe requests collected in a university campus for 15 days.file: University.tar.gzdescription: This traceset contains 418 pcap traces (of ~1M each), collected by deploying an antenna in a fixed vantage point located at one of the main entries of the Sapienza University campus. Differently from the other datasets, in this case we collected probes continuouslyfor 6 weeks days (28th of March, 2013 - 6ht of May, 2013), monitoring students as they entered and left the campus.measurement purpose: Social Network Analysis, Human Behavior Modelingsapienza/probe-requests/University TraceUniversityformat: This trace contains 418 pcap files compressed in an unique tar.gz archive.sapienza/probe-requests/TheMallProbe requests collected at one of the biggest malls in Rome.file: TheMall.tar.gzdescription: This traceset contains 7 pcap traces collected at a mall in Rome. For this case study we aimed at collecting data from local Rome residents. So, we targeted a location known for hosting many families and groups of ffriends all at once: One of the biggest malls in Rome ("Porta di Roma"). To be sure to get a relevant affluence of people, we chose to collect the data on a special afternoon, that right before Easter (March 30th). The collection lasted 3 hours and a half.measurement purpose: Social Network Analysis, Human Behavior Modelingsapienza/probe-requests/TheMall TraceTheMallformat: This trace contains 7 pcap files compressed in an unique tar.gz archive.sapienza/probe-requests/TrainStationProbe requests collected at Roma Termini central station.file: TrainStation.tar.gzdescription: This traceset contains 17 pcap traces collected at Roma Termini central station. In this case study we targeted Rome central station and collected the probes for a total of 7 hours split in a time range of four days. The collection was carried out by positioning ourselves at advantage points in the station so as to maximize the area covered.measurement purpose: Social Network Analysis, Human Behavior Modelingsapienza/probe-requests/TrainStation TraceTrainStationformat: This trace contains 17 pcap files compressed in an unique tar.gz archive.sapienza/probe-requests/OthersProbe requests collected by 3 students around Rome.file: Others.tar.gzdescription: This traceset contains 91 pcap traces, collected by 3 students during several tours across the city performed in a time span of 4 weeks while e.g., commuting from home to the university or shopping.measurement purpose: Social Network Analysis, Human Behavior Modelingsapienza/probe-requests/Others TraceOthersformat: This trace contains 91 pcap files compressed in an unique tar.gz archive.