The FS uses the 'nat-options-ping' to keep the client natted hole open BUT it does not provide the round-trip-delay of the sent message. Is there a way to send a kind of SIP/OPTION messge from the FS to a specific remote client (not a global setup) and measure the round-trip-delay of that message? Regards -- View this message in context: http://freeswitch-users.2379917.n2.nabble.com/How-to-measure-Round-Trip-Dela... Sent from the freeswitch-users mailing list archive at Nabble.com.