Session Announcement Protocol (SAP) is a protocol to announce available Multicast streams in local networks. Clients on the network listens for announces and receives information such:
Astra send SAP packets to the multicast group 22.214.171.124 port 9875.
In the Output address append
sap option to turn the SAP announcements on.
Open VLC Media Player and in the Playlist select Local Network -> Network streams (SAP). VLC receives SAP announcements and list all available streams. Double click on the stream to start playing.