Skrót:
Nadawca SAP cyklicznie rozgłasza na dobrze znany adres i port pakiety multicast z opisem sesji SDP. Ogłasza w tym samym scopie w ktorym jest sesja. Mozliwe przypadki:
IPv4 global scope sessions use multicast addresses in the range
224.2.128.0 - 224.2.255.255 with SAP announcements being sent to
224.2.127.254 (note that 224.2.127.255 is used by the obsolete
SAPv0 and MUST NOT be used).
IPv4 administrative scope sessions using administratively scoped IP
multicast as defined in [7]. The multicast address to be used for
announcements is the highest multicast address in the relevant
administrative scope zone. For example, if the scope range is
239.16.32.0 - 239.16.33.255, then 239.16.33.255 is used for SAP
announcements.
Port docelowy w pakietu UDP to 9875.
Pakiety sam możemy generowac programem [http://www-mice.cs.ucl.ac.uk/multimedia/software/sdr/]