Q-Flex Satellite Modem Installation and Operating Handbook
6-63
timestamps as required, potential jitter in the play out of the packets at the
receiver/decoder can be eliminated.
6.2.3.8 MPEG Over IP Type
UDP/TS
This indicates that the MPEG2 transport stream packets are
encapsulated into into IP packets using the UDP protocol
.
UDP/RTP/TS
This indicates that the MPEG2 transport stream packets are
encapsulated into into IP packets using the UDP and RTP
protocols
.
Table 6-65 MPEG Over IP Type
When sending MPEG2 packets encapsulated inside IP packets, the modem can reduce
the satellite transmission overhead by removing the IP headers and sending only the
MPEG2 packets. On the receive side, the MPEG2 packets are encapsulated back into IP
packets, using IP address and port number information entered by the user. When
decapsulating and encapsulating MPEG2 packets, the modem needs to know whether
the IP packets contain just UDP headers, or UDP and RTP headers.
6.2.3.9 Destination Address and Destination Port
Destination
address
When using MPEG2 over IP, the IP packet wrapper is discarded in order
to save satellite bandwidth. The user-entered destination address is
therefore used on the receive side in order to recreate a copy of the
original IP packet.
Destination
port
The destination UDP port number is used in a similar way to to the
destination address above, when creating a copy of the original IP packet
in order to wrapper received MPEG2 packets.
Table 6-66 Destination Address & Destination Port
6.2.3.10 Local Multicast Address and Local Port
Local
multicast
address
When using MPEG2 over IP, the modem can listen on a local multicast
address in order to detect packets to be sent over satellite.