Adtec RD-71, User Manual

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packet.
TCP ( Transmission Control Protocol ) support, a connection based protocol, has recently
been added at an attempt to overcome some of the fundamental limitations of UDP and
RTP. UDP and RTP are ‘one way street’ types of protocols where the transmitter sends data
and never knows if the data makes it to the destination. TCP streams generally have higher
latency ( takes longer to transmit data and verify data has been transmitted ), but are more
reliable because each packet is accounted for by the receiver. If a packet is lost, the
transmitter will be informed to re-transmit the packet. The transmitter and receiver
continue to communicate about the quality of the reception and attempt to adjust packet
delivery accordingly. The TCP mechanism when combined with large IP receive buffers can
be more forgiving with packet loss, jitter, and out of order packets. The RD-71 supports up
to 15Mb/s when a 7 DVB Packet payload exists for each TCP packet. Multicast is
​
not
supported with TCP streams.
The RD-71 supports both unicast (point to point) and multicast (broadcast) streams. The
RD-71 operates in UDP/RTP mode by default. To setup an IP Rx session, first configure the
IP Rx operation mode. A unit reboot is required (WebUI asks for confirmation when
changing) when changing between UDP/RTP Rx and TCP Rx modes.
Multicast Reception - Address
To receive a multicast (UDP/RTP/SMPTE2022) stream, place the multicast address wished to
view in the ‘Address’ field. This address must match the same address used on the
multicast transmitter. Multicast IP address ranges are 224.xxx.xxx.xxx to 239.xxx.xxx.xxx,
where 0 <= xxx <= 255. If you are new to multicast and attempting a first time
connection, 226.0.1.1 is a common address to start with. Please verify transmitter address
configuration.
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