CRAWDAD unimi/pmtr

Dataset of mobility traces collected by Pocket Mobility Trace Recorder devices at University of Milano.

This dataset contains mobility traces from 44 mobile devices at University of Milano. The data was collected in November 2008.

date/time of measurement start: 2008-11-13

date/time of measurement end: 2008-12-01

collection environment: The experiment lasted for 19 days in November 2008. 49 Pocket Mobile Trace Recorders (PMTRs) were distributed to faculty members, PhD students, and technical staff. These people work in offices and laboratories located in a three-floor building, roughly 200x100 m large and take lunches or coffee breaks in a nearby cafeteria. Some of the classes take place in a different building 3.5 Km away. These locations were equipped with fixed PMTRs.

network configuration: The need to observe and record very short contact periods that arise from human mobility motivated the design of a specific custom hardware device for trace recording. Pocket Mobile Trace Recorders (PMTRs) have been designed to operate with beaconing times ranging from 1 sec. to some configurable value, which depends on the mobility environment we wish to observe. The PMTR architecture uses the Cypress CY8C29566 micro-controller and the radio module AUREL, model RTX-RTLP. The radio range has been limited to 10 meters in order to reduce the power consumption and to maintain multi-hop paths between end-systems. This combination allows a very low power consumption that lets the experiments last for the required time with common batteries NiMh, AA 1.2 V. Each PMTR has a 1 MB flash memory where more than 50K contacts can be stored. The PMTR implements a CSMA non-persistent MAC protocol. The local clock value is set at the configuration time. Each PMTR uses a USB interface to communicate with the Pocket Viewer PC, running the Desktop application software, which has been used to configure the devices, collect the recorded data at the end of the experiment, and support data analysis and device monitoring.

data collection methodology: Recorded data was collected at the end of the experiment. Symmetric contacts, that is contacts recorded by both devices approximately at the same time, were kept for analysis; unidirectional contact records were discarded. This resulted in a collection of 11895 contacts between 44 PMTRs.

limitation: This traceset contains mobility traces from 44 mobile devices at University of Milano. The data was collected in November 2008.

hole: At the end of the experiment, 5 PMTRs (with IDs 5, 8, 15, 30 and 35) had not registered any contacts due to hardware failure.

Traceset

unimi/pmtr/txt

Mobility traces collected by Pocket Mobility Trace Recorder devices at University of Milano in November 2008.

• file: pmtr.txt.gz
• description: This traceset contains mobility traces from 44 mobile devices at University of Milano. The data was collected in November 2008.
• measurement purpose: User Mobility Characterization, Positioning Systems, Social Network Analysis, Human Behavior Modeling, Localization, Opportunistic Connectivity

unimi/pmtr/txt Trace

• gz: Mobility traces collected by Pocket Mobility Trace Recorder devices at University of Milano in November 2008.
• configuration: This trace contains contact records from 44 mobile devices. The records were collected at University of Milano in November 2008.
• format: The format of the file is:

id_source id_destination t_start_contact t_end_contact

where times are expressed in seconds, starting from 0 (start of the experiment).