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Operation Manual – VPLS
H3C S9500 Series Routing Switches
Chapter 1 VPLS Configuration
1-3
A tunnel, usually an MPLS tunnel, is a direct channel between a local PE and the peer
PE for transparent data transmission in-between. It is used to carry PWs. A tunnel can
carry multiple PWs.
z
Encapsulation
Packets transmitted over a PW use the standard PW encapsulation formats and
technologies: raw and tagged.
z
PW signaling
The PW signaling protocol is the fundament of VPLS. It is used for creating and
maintaining PWs and automatically discovering VSI peer PE. Currently, there are two
PW signaling protocols: LDP and BGP.
z
QoS
Quality of service (QoS) is implemented by mapping the preference information in the
packet header to the QoS preference information transferred on the public network.
Figure 1-1
shows a typical VPLS networking scenario.
Figure 1-1
Network diagram for VPLS
II. MAC address learning and flooding
VPLS provides reachability information by learning MAC addresses. Each PE
maintains a MAC address table.
1)
Source MAC address learning
MAC address learning includes two parts:
z
Remote MAC address learning associated with PWs
A PW consists of two unidirectional VC LSPs. A PW is up only when both of the VC
LSPs are up. When the inbound VC LSP learns a new MAC address, the PW needs to
map the MAC address to the outbound VC LSP.