Zte ZXR10 8900E series, Описание продукта

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ZXR10 8900E series Core Switch Product Description
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Figure 3-7 Basic VPLS network model
3.3.3.2 H-VPLS
VPLS adopts PE full-connection to avoid loopback so that LDP session or BGP session
will be set up between all PEs in one VPLS instance, which brings great challenge to
network scalability. In scenario with medium scale, PE full-connection is acceptable. But
when PE increases in network, the number of sessions will grows by a square increase,
which put high requirement of equipment performance. At the same time network
management becomes very complicated. Hierarchical VPLS networking (H-VPLS)
perfectly solve this problem.
H-VPLS divides PE into NPE and UPE. UPE works as CE for access user. NPE works as
core layer of VPLS networking, providing transparent transport of user packet in
operator’s network. NPEs in H-VPLS networking compose full-connection. UPE doesn’t
need to establish connection with all PEs. With hierarchy, H-VPLS reduces PW number
and PW signaling costs.
There are two types of H-VPLS: PW and QinQ.
1. U-PW Access:
Figure 3-8 H-VPLS networking with U-PW access