Cobalt Digital COMPASS 9223 Dual-Channel 3G_HD_SD MPEG-4 Encoder - Manual (Page 72)

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9223-OM (V2.0)
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Null Padding: The configured value of this parameter (shown as No, Auto, or Manual).
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TOS: The configured value of this parameter.
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TTL: The configured value of this parameter.
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DF: The configured value of this parameter.
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RTP: The configured value of this parameter.
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FEC: Summary of the FEC configuration. If FEC is disabled, this field will indicate it as
Off. If FEC is enabled, this field will indicate the FEC matrix size as Columns × Rows,
and the protection mode as C for Column Only or R-C for Row and Column. In the
example above, Stream 1/1 has Column Only FEC with 1 Column and 4 Rows, and
Stream 2/1 has Row and Column FEC with 4 Columns and 10 Rows.
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Destination MAC: The destination MAC address for this IP Output. For multicast
destination addresses, this is derived from the destination IP address using the rules from
RFC 1112. For unicast destination addresses, this is obtained using the ARP protocol. If
this entry is the word Unknown, the 9223 has failed to obtain a destination MAC
address. The IP Output is
not streaming. A more detailed description of the unicast
MAC address algorithms used in the 9223 is presented below.
Managing Unicast MAC Addresses
When the 9223 is configured with a unicast destination address, it needs to obtain a
corresponding MAC address (corresponding to either the final destination, if it is in the same
subnet, or to the default gateway). These MAC addresses are obtained using the ARP protocol.
The 9223 uses a custom MAC address management algorithm, designed specifically for MPEG
operation.
When an IP Output stream with a unicast destination address is created, the 9223 immediately
starts attempting to obtain a MAC address for it, using standard ARP requests. These requests
are issued every two seconds until answered. No packets will be transmitted on that IP Output
until a MAC address can be obtained. Note that this process will happen even if the stream is
configured to be in the disabled state.
Once a MAC address is obtained, the 9223 will cache it for about 5 minutes, as it is usual for IP
devices. Unlike other IP devices, the 9223 will keep on using the MAC address until a response
is received, to avoid stream interruptions. If no response is received at that time, the 9223 will
raise a yellow alarm. This alarm can be seen in the IP Output Statistics tab, described in detail
below.
The current state of the 9223 current streaming ARP cache is available in the Advanced View of
the Active IP Outputs table, described above.
IP Outputs: Statistics Tab
The Statistics tab for the IP output ports contains a summary of each stream status. There are
two sub-tabs: one for Ethernet 1, and another for Ethernet 2. The tab is depicted below: