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Office Surveillance: Locating And Tracking 802.11b

Posted by timothy on from the oh-really-mister-anderton dept.

securitas writes "The NY Times recently ran an article about locating and tracking users of 802.11b WiFi networks in three dimensions using triangulation (Google) with multiple base stations. The goal is to create context-aware networks that can allocate bandwidth and provide location-based services such as uploading relevant information to a PDA. The article can be seen in a new light when coupled with the growth in workplace surveillance of employees by corporate executives (Google / short version at IHT) and the associated practical, ethical and legal problems. Interlink Networks 802.11 wireless detection and tracking white paper (PDF)." (This seems as good a place as any to mention Kensington's handheld 802.11 detector; they claim it to be the only such device on the market today. This is the cheapest detector I've seen; have the others all disappeared?)

3 of 120 comments (clear)

  1. Slightly OT, but here's a nice OSS tool... by pen · · Score: 5, Informative

    AirTrafis a 100% passive packet sniffing tool for the wireless 802.11b networks. It captures and tracks all wireless activity in the coverage area, decodes packets, and maintains acquired information associated by access points, as well as detected individual wireless nodes. It dynamically detects any access points in the area, finds association between wireless clients and access points, and builds information table for each packet that is transmitted via the air. AirTraf is able to maintain packet count, byte information, related bandwidth, as well as signal strength of nodes.

  2. This has been around for a while by Jarit99 · · Score: 5, Informative

    The same discussion seems to be popping up every 6 months or so. Check out what companies such as Ekahau and BlueSoft are offering.

  3. Re:How well does this work in indoor environments? by Anonymous Coward · · Score: 5, Informative

    Almost.

    TRIangulation works exactly as you say (except the tri means 3 measurements only). Multiangulation uses >3 measurements in the same way.

    When you have ranges (i.e. distances as derived from signal attenuation), it's called lateration. Trilateration == 3 ranges. Multilateration == >3 ranges.

    However, triangulation is commonly used when lateration is meant, just because people are more familiar with the term.