This paper presents a new method to estimate
the available bandwidth and the path capacity over a wireless
network path, denoted as rt-Winf. The estimation is performed
in real-time and without the need to intrusively inject packets in
the network. This is accomplished by resorting to the CSMA-CA
scheme with RTS/CTS packets to determine each node’s channel
allocation. rt-Winf repeatedly samples the available bandwidth of
the network path, requiring little computation in each iteration,
and being lightweight with respect to memory requirements. rt-
Winf has been tested both in the CMUWireless Emulator and the
ns-2 simulator, using ad-hoc, infrastructure and mesh networks
scenarios. The results obtained through the comparison of rt-
Winf with current state of the art approaches show that rt-Winf
obtains the available bandwidth and capacity estimation with the
highest accuracy and without introducing overhead traffic in the
network.