Cobalt Digital Inc BBG-1090-DEC-MPEG Product Manual page 31

• Primary Reception: select between Unicast and Multicast. In Unicast mode, the
stream must be sent to the decoder's streaming port IP address (see the Network Tab). In
Multicast mode, the decoder will join an IP Multicast stream. When this mode is
selected, a new field appears for the multicast address:
o Primary Multicast Address: enter the desired IP multicast address. The decoder
will only accept addresses between 224.0.0.0 and 239.255.255.255 in this field.
• Primary UDP Port: enter a valid UDP port. Valid values are between 1 and 65535.
Note that RTP requires that the UDP port be even (multiple of 2). ARQ, if present, will
use the next UDP port. For example, if the UDP port is set to 2042, ARQ will be on port
2043.
• NACK Window (ms): enter the window, in milliseconds, for the NACK packets. The
value entered here should be at least equal to the round-trip delay between the encoder
and the decoder. For best possible performance, use 3 to 4 times the round-trip delay, so
the decoder has multiple chances of recovering a lost packet. Note, however, that the
value of the NACK window adds to the end-to-end (glass-to-glass) latency.
• NACK Target: this parameter controls to which IP address the decoder will send the
NACK packets. The options are:
o Source IP: if this is selected, the decoder will send the NACK packets to the
source IP address of the received bitstream. This is the most common case, when
there are no firewalls between the encoder and decoder, or when the firewall at
the encoder is configured to forward the packets transparently.
o Custom IP: if this is selected, a custom IP address can be specified for the NACK
packets. The decoder will send NACK packets to this IP address. When this is
selected, the following field appears:
• ARQ Sender Address: send the NACK packets to this IP address instead of
the source IP address of the received bitstream packets.
• Redundant Reception: if this box is checked, a backup UDP flow can be configured. If
the Decoder stops receiving packets in the primary flow, it will switch to the backup.
When this box is checked, the following new fields appear:
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