Yes you can do that but that runs up against the problem of "processing time" in the router. A router might process a simple echo request for +/- 1 millisecond.

Yes you can do that but that runs up against the problem of "processing time" in the router. A router might process a simple echo request for +/- 1 millisecond. Since 1 nanosecond = 1 foot, this variability already makes the distance measurement meaningless for indoor positioning. The way to do it accurately requires using something like 802.11mc [1] which can vary accurately measure time using frame collisions. [1] http://ieeexplore.ieee.org/document/6805649/ http://ieeexplore.ieee.org/document/6805649/