This visualization shows Round-trip time (RTT) measured in
milliseconds. RTT is the length of time it takes for a data packet
to be sent from the client to the server and back.
RTT affects application responsiveness: A high RTT value means that
an application server's response to a client request is slow. RTT
also affects end user experience in audio and video streaming
applications, because a high RTT value will inevitably cause a VoIP
lag. Varying RTT might also cause VoIP jitter.
When the surveyor walks the facility during an active survey, the
adapter periodically renegotiates the PHY rate and roams to new
APs. During these periods of time, RTT values might peak, which is
When areas with consistently high RTT are discovered, the following
solutions are suggested:
Common reasons for high RTT values are interference and excessive
network traffic. The Signal-to-Interference Ratio visualization
available for passive surveys might provide insight into
interference issues. Excessive network traffic might be caused
either by oversubscription (too many clients per AP) or by
excessive network load by some clients. The former can be addressed
by increasing the number of APs, while the latter should be
verified and handled by network traffic monitoring software.