==linphone and freeswitch==
* Reduce latency of talk.
* Stun talk
* IGMP cross internet or fall back to conference talking
** PIM? perhaps
* IGMP/Broadcast must consider sync audio contents when losing packets or received out of order packets
** perhaps we need to hack into RTP packet or audio packet on both side of software.
* IGMP/Broadcast discover server/client
* IGMP/Broadcast must handle mix internet condition: clients inside LAN and WAN.
* Direct media flow allow audio recording.
*  error concealment algorithms on losting of packets
== packets discovery tools==
* see all packets flow in/out routers/switches
* see all packets flow in/out computer/server/client