a new filter is to be added while the number of packets field indicates that a single packet is to be added note that the sr_id value sd_id u2014 1 is the same as the original packet filter for the on going rtp flow as noted with reference to step 1 the tft further specifies the ip address and port number of the mgw 15 note that during the rsvp and sip messaging steps 3 and 4 the original peer to peer rtp flow is ongoing as shown at step 5 to facilitate such ongoing rtp flow pdsn a 11 utilizes the original packet filter to match forward direction rtp packets from hat b 10 a to hat a 10 in order to obtain a seamless hand down the original packet filter is not yet deleted at step 6 pdsn a 11 responds to hat a 10 with a rsvp response message the rsvp response message serves to notify the hat a 10 that the packet filter indicated in the rsvp message of step 4 was received and added after the success of the rsvp messaging steps 4 and 6 hat a 10 sends a sip 200 ok message to the sip.