In a host using VoIP software continuous dial twice, why inquires in the gateway and gatekeeper displays there are two concurrent traffic currently.
In the VOIP detection, SPS will not detect the signaling message related with on-hook, only extracts number information from signaling and associates the signaling flow with media flow. VOIP session is aging by the SPS according to media flow. SPS will aging the session if has not received the media data package of the session for a minutes. Therefore, when the user hang up, continuous dialing in a minute, SPS hasn’t aging the pre conversation and creates new conversation, thus accumulated to have two concurrent traffic.