Patent ID: 7672283
Filing Date: 2010-03-02
Classification: H04W

Abstract:
1. A computer-implemented method for ascertaining whether a wireless device exists in a network, comprising: sending a plurality of test packets over a monitoring period to a first device, said plurality of test packets being sent in a temporally spaced-apart manner; receiving responses to said plurality of test packets from said first device; ascertaining a first set of RTT (Round Trip Time) values, each of said first set of RTT values corresponding to one of said plurality of test packets; computing a first set of statistical values from said first set of RTT values, said first set of statistical values including at least a first standard deviation value for said set of RTT values and one of a first average RTT value and a first minimal RTT value for said first set of RTT values; designating said first device a potential wireless device if both a first condition and a second condition are found, said first condition is characterized by said at least one of said first average RTT value and said first minimal RTT value exceeds a corresponding one of a reference average RTT value and a reference minimal RTT value, said reference average RTT value representing an average RTT value for known wired devices in said network, said reference minimal RTT value representing a minimal RTT value for said known wired devices in said network, said second condition is characterized by said first standard deviation value exceeding a confidence interval established for a standard deviation value associated with said known wired devices; after said designating, investigating whether said first device is wireless; after said investigating, if said first device is determined to be a wired device, updating said reference average RTT value to an updated average RTT value and said reference minimal RTT value to an updated reference minimal RTT value; and based on said updating, changing a probability that a second device is wireless to an updated probability.