Cobalt Digital COMPASS 9223 Dual-Channel 3G_HD_SD MPEG-4 Encoder - Manual (Page 68)

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9223-OM (V2.0)
Advanced
Parameters
•
TOS: This parameter allows the configuration of the Type-Of-Service (TOS) byte in the
IP header (also known as the Differentiated Services – DS – field). Valid values are
between 0 and 255. Configuring this is only useful if the downstream router is
configured to honor the field.
•
TTL: This parameter allows the configuration of the Time-To-Live (TTL) byte in the IP
header. Valid values are between 0 and 255. If not explicitly configured, it defaults to
128. This field controls how many hops the packet can traverse before it is dropped by a
router. The default value of 128 is suitable for virtually all applications.
•
DF Bit: This parameter allows the configuration of the Do-not-Fragment (DF) bit in the
IP header. The 9223 will never produce fragmented packets, and with the UDP payload
set to 7 transport packets, the IP packets are guaranteed to fit inside the Ethernet MTU.
This control is provided for compatibility with legacy switches/routers. Some legacy
equipment may exhibit performance problems if this bit is not set. This is not an issue
with current network equipment.
•
RTP: If this box is checked, the 9223 will include RTP (Real Time Protocol) headers in
the output flow. If it is not checked, the transport stream will be sent over UDP/IP
without any additional headers. Note that RTP requires the use of even UDP port
numbers; when this box is checked, the user interface will enforce this restriction. The
9223 will not generate RTCP packets.
If the RTP box is checked, an additional control to enable SMPTE 2022 FEC may be displayed
if a FEC session is available for configuration. The 9223 only supports one FEC session per
Ethernet port; once FEC is enabled on a given stream, this option will not be offered for the other
streams in the same port. This is depicted below: