Media Links MD8000 Series, Руководство по эксплуатации

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MD8000 Rev. H MD8000 Series Transport System Summary 2.11
Class J
The Class J mode runs under the “ Dual SWCNT/Dual Trunk ” configuration to support Hitless
switching. Figure 2-5 illustrates the flow of packets.
Figure 2-5: Class J Mode Of Operation To Support Hitless Switching
In the originating System (#1), the Channel Service board duplicates the encapsulated video
signal with the different MAC addresses “M1-1” and “M1-2” and delivers them to each
corresponding SWCNT board in CPU-ACT or -STB state. (See
Dual SWCNT Operation, page
2.33 for Dual SWCNT operation.) Each SWCNT board passes them to the corresponding
Trunk board. The Trunk boards transmit the supplied packets to the network.
In the receiving System (#2), two Trunk boards transfer the received packets to the
corresponding SWCNT boards (ACT or STB), which pass the received packets to the “Line 1”
input of the destination Channel Service board or “Line 2” input of the same destination
Channel Service board. The output video signal is reproduced from either the “M1-1” or
“M1-2” stream selected by the Hitless switching module.