GE Reason H49, Техническое руководство

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GE Reason H49 Technical Manual
H49/EN M/C22 27
The HSR RedBoxes for connecting the ring to a PRP network operate identically to
those used to attach SANs, except that they are configured as RedBox “A” or RedBox
“B” to accept PRP frames on their interlink. In the figure here above, RedBox A and
RedBox B would send the same frame (A and AB, respectively B and BA), but if a
RedBox receives the frame before it could send it itself, it refrains from sending it.
In the figure here above, RedBox A will not generate an “A“ frame on behalf of LAN A if
it previously received the same frame as “AB“ from the ring, or conversely, RedBox “B”
will generate an “AB” frame if it did not previously receive an “A” frame from the ring,
which is the case whenever frame “A” is not a multicast frame.
Multicast frames or unicast frames without a receiver in the ring (see figure here
above) are removed by the RedBox that inserted them into the ring, if they originated
from outside the ring.
The following figure shows the same coupling when the source is within the ring.
DANH
S1608ENa
DANH
DANH
DANH DANH
"B"
Destination
LAN A
LAN B
"BA"
DANP DANP
Source
“A” frames
“B” frames
duplicated redundant frames
frame is removed from the ring by the node
"A" "AB"
H49
RedBox
“A“
H49
RedBox
“B“
Figure 8: Coupling an HSR Ring to two PRP LANs