Cobalt Digital Inc BBG-1090-TRX-MPEG, Руководство по эксплуатации продукта

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The Advanced view includes all items in the Basic view plus the following:
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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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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 BBG-1090-TRX-MPEG has failed to obtain a
destination MAC address. The port is
not streaming. A more detailed description of the
unicast MAC address algorithms used in the BBG-1090-TRX-MPEG is presented below.
Managing Unicast MAC Addresses
When the BBG-1090-TRX-MPEG 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 BBG-1090-TRX-MPEG uses a custom MAC address management algorithm,
designed specifically for MPEG operation.
When an IP Output port with a unicast destination address is created, the BBG-1090-TRX-
MPEG 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 port is configured to be in the disabled state.
Once a MAC address is obtained, the BBG-1090-TRX-MPEG will cache it for about 5 minutes,
as it is usual for IP devices. Unlike other IP devices, the BBG-1090-TRX-MPEG 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 BBG-1090-TRX-MPEG 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 BBG-1090-TRX-MPEG current streaming ARP cache is available in the
Advanced View of the Active IP Outputs table, described above.