Cobalt Co9992-4ENC-4K-HEVC Software-Defined Broadcast Encoder - Manual (Page 94)

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The Advanced view includes all items in the Basic view plus the following:

Line Rate: This column replaces the TS Rate column in the Advanced view. It indicates
the actual Ethernet line rate for the stream, including the MAC, IP, UDP, RTP and FEC
overheads.

Null Padding: The configured value of this parameter (shown as No , Auto , or Manual ).

TOS: The configured value of this parameter.

TTL: The configured value of this parameter.

DF: The configured value of this parameter.

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 9992-ENC 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 9992-ENC is presented below.
Managing Unicast MAC Addresses
When the 9992-ENC 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 9992-ENC 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 9992-ENC
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 9992-ENC will cache it for about 5 minutes, as it is usual
for IP devices. Unlike other IP devices, the 9992-ENC 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