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From CUSystems

This dataset is now available from CRAWDAD.

Overview

This data set provides a comprehensive set of received signal strength indication (RSSI) readings from within an indoor office building from several perspectives throughout the building. This data captures RSSI behavior when 802.11 frames are transmitted using:

• a stock omnidirectional antenna
• an inexpensive directional antenna
• transmit power control

Omnidirectional RSSI measurements are collected from roughly 180 distinct physical locations throughout a large office building. To quantify how the transmitter's received signal strength varies with their physical location in the building, we transmit 500 packets from each of the 180 physical positions. Since the human body tends to attenuate 2.4 GHz transmissions, we transmit packets while facing each of the four cardinal directions. All measurement packets are recorded by 5 passive monitors, which are commodity linux machines with 802.11 cards. Each RSSI measurement is labeled with the transmitter's physical location.

In addition, at each of the 180 measurement locations, we transmit 500 packets in each of the four cardinal directions using transmit power control. Frames are transmitted at each transmit power level between 10-20 dBm.

We also have a limited number of measurement points where the packets are transmitted using an inexpensive directional antenna commonly called a "cantenna". Transmit power control is also applied. The cantenna that we used is displayed below.

The office building environment is a single storey building measuring roughly 50 x 70 meters. The interior consists of small offices, cubicles, long hallways, and large warehouse-like rooms. A floor plan of this environment with measurement points and the passive monitors' locations labeled is provided below.

This data set was collected by researchers at the University of Colorado over the course of one day in August 2007.

Data

We provide the data as processed text and raw pcap files.

Text files:

• RSSI measurements with a constant transmit power level of 16 dBm using an omnidirectional antenna: "Constant transmit power level, omnidirectional antenna"
• RSSI measurements with a variable transmit power level between 10-20 dBm using an omnidirectional antenna: "Variable transmit power levels, omnidirectional antenna"
• RSSI measurements with a variable transmit power level between 10-20 dBm using a directional antenna: "Variable transmit power levels, directional antenna"

The raw pcap traces have been anonymized and all background traffic has been filtered. They contain all three data sets combined in each pcap file:

• Raw pcap traces: "Raw pcap traces"

The pcap files are named by their monitor number (as shown in the floor plan below). For example, the pcap file captured at monitor #1 is named 1_anon.pcap.

Data Format

The processed text data files consists of the following information:

    <x coordinate> <y coordinate> <transmit power level (in dBm)> <directional transmitter? (y/n)> <rssi values from monitors 1...5>

The raw pcap files contain the constant transmit power level omnidirectional, variable transmit power level omnidirectional, and variable transmit power level directional data. The RSSI values are contained within the "RSSI" field of the prism header. The transmitter's location is encoded as a 32 byte UDP payload string of the following format:

    [T:C:]<x coordinate>:<y coordinate>:<K=dev1 or E=dev2>:<orientation in {0, 1, 2, 3}>:<transmit power level (in dBm)>:<sequence number>

If the string is less than 32 bytes, then it is padded with nulls. "Orientation" denotes which direction the human data collector is facing while transmitting packets. 0 is "down", 1 is "left", 2 is "up", and 3 is "right". These directions are relative to the building's floor plane provided above. "[T:C]" indicates that the directional antenna was used; otherwise, an omnidirectional antenna was used.

An example of an omnidirectional measurement point in the pcap trace:

    1:8:K:0:16:0

The omnidirectional transmitter is positioned at x=2.4384, y=19.5072; K=dev1 card was used; orientation=0 ("down"); transmit power=16 dBm; sequence number=0.

An example of a directional measurement point in the pcap trace:

    T:C:7.5:14.5:E:0:10:105

The T:C=directional transmitter is positioned at x=18.2880, y=35.3568; E=dev2 card was used; orientation=0 ("down"); transmit power level=10 dBm; sequence number=105.

Note: the coordinate system used in the pcap files is on a different scale than the coordinate system in the text data files. To convert the pcap data's coordinates to the text data's coordinates, simply multiply the pcap's coordinates by 2.4384.

Hardware Specifications

Monitors: D-Link DWL-AG530 card with omnidirectional dipole antenna 2-4 dBi

Transmitters: WNC WLAN Cardbus Adaptor CB9 card with omnidirectional dipole antenna 2-4 dBi

Directional Transmitters: WNC WLAN Cardbus Adaptor CB9 card with "Super Cantenna" (shown above) 12 dBi 30 degree beam width directional antenna

Publications

Proceedings of the IEEE Globecom 2009 Communications and Information Security Symposium , Honolulu, HI, USA, November, 2009

Bibtex

Author : Kevin Bauer, Damon McCoy, Eric Anderson, Markus Breitenbach, Greg Grudic, Dirk Grunwald, Douglas Sicker
Title : The Directional Attack on Wireless Localization - or - How to Spoof your Location with a Tin Can
In : Proceedings of the IEEE Globecom 2009 Communications and Information Security Symposium -
Adress : Honolulu, HI, USA
Date : November 2009

Proceedings of the Ninth Privacy Enhancing Technologies Symposium (PETS 2009) , Seattle, WA, USA, August, 2009

Bibtex

Author : Kevin Bauer, Damon McCoy, Ben Greenstein, Dirk Grunwald, Douglas Sicker
Title : Physical Layer Attacks on Unlinkability in Wireless LANs
In : Proceedings of the Ninth Privacy Enhancing Technologies Symposium (PETS 2009) -
Adress : Seattle, WA, USA
Date : August 2009

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