Zte ZXR10 8900E series, Описание продукта

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ZXR10 8900E series Core Switch Product Description
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Figure 3-1 MC-ELAM structure
Normally, only half of the links from CE to PE1 and PE2 are aggregated successfully. As
shown in the above figure, the successfully aggregated link from CE to PE1 is active link;
the non-aggregated link from CE to PE2 is standby link; data stream is forwarded via
active link. When active aggregation equipment PE1 goes wrong, PE2 will release the
MC-ELAM control protocol signal of PE1 to process the LACP forwarding between PE2
and CE. When active equipment or active aggregation equipment returns to normal,
MC-ELAM control protocol will recover the forwarding process. MC-ELAM can access the
dual-uplink access network to increase network redundancy.
3.1.4 Spanning tree
3.1.4.1 STP
STP detects and clears the loop between L2 switching functional units, and provides
redundancy link to improve LAN performance and reliability.
STP module has the following major functions:
Avoid network loop, prevent LAN broadcast storm, and offer redundant path.
Detect topology change and reconfigure STP topology accordingly.
After the switch in one subnet executes STP algorithm, one STP dynamic topology is
formed. The topology prevents the loop between any two workstations in LAN to avoid
LAN broadcast storm. Meanwhile, STP algorithm monitors topology change, create the
new spanning tree after the change, and reconfigure spanning tree topology with fault
tolerance. The switch maintains and updates MAC route table according to the status of
STP dynamic topology, and finally gains the MAC-layer route.
STP algorithm aims to enable the switch to dynamically discover a no-loop subset (tree)
in topology and assure adequate connectivity so that a path is available between every
two LAN if the physical conditions allows. According to the principle in the figure, any line