Sessions initiated by SIP signalling protocol imply media streams shared by involved entities.
This media streams use RTP to send and receive the media itself, usually using UDP as a transport protocol.
External entities involved in RTP sessions can be divided in:
- Clients endpoints.
- Carriers/DDI Providers.
Both entities exchanges RTP with the same IvozProvider entity: media-relays.
IvozProvider implements media-relays using RTPengine.
Similar to SIP, these media-relays exchanges RTP when is needed with Application Servers, but external entities never talk directly to them.