Users in JanusVR are able to teleport through space. These attributes allow web developers to set limits on the minimum and maximum teleport distances.
http://janusvr.com/docs/build/roomtag/index.html#Room
teleport_min_dist - (default "5.0") The minimum cursor distance in meters needed to allow teleporting.
teleport_max_dist - (default "100.0") The maximum cursor distance in meters needed to allow teleporting.