How we will get _resumeToken value?

in _tryResumingConnection() function in XmmpConnection.js I am getting streamManagement.getResumeToken() as undefined can any one tell how this value is been set?

Have you enabled smacks? jitsi-meet/mod_smacks.lua at master · jitsi/jitsi-meet · GitHub

yes, but we are using HTTP bind not WebSocket…so it will work for HTTP Bind?

Nope. Bosh uses a field called sid to resume the connection.