HP Intelligent Management Center Licenses - Manual (Page 9)

The figure shown above illustrates a typical H-VPLS network, which involves the following basic
concepts:
•
UPE (User Facing-Provider Edge): User facing provider edge device that functions as the user
access convergence device.
•
NPE (Network Provider Edge): Network provider edge device that functions as the network
core PE. An NPE resides at the edge of a VPLS network core domain and provides transparent
VPLS transport services between core networks.
•
U-PW: PW link between a UPE and an NPE.
•
N-PW: PW link between two NPEs.
VPLS VPN Types
•
LDP VPN: Uses the Label Distribution Protocol (LDP) to establish virtual circuits by establishing
point-to-point sessions between a pair of PEs.
•
BGP VPN: Uses the Border Gateway Protocol (BGP) to establish signaling sessions through
route reflectors (RRs) and supports networking across ASs.
Operation of VPLS
The icon descriptions for the data forwarding flowchart shown above are:
•
L2-pdu: Data link layer packet.
•
Dmac: MAC address of the next hop device.
•
Smac: MAC address of the local device.
•
L: Public network label.
•
V: Private network label.
•
L': Public network label after the packet is forwarded along the LSP.
The data forwarding procedure is as follows:
1. A PE receives a data packet from a CE through the AC. According to the VSI, the PE pushes
its own MAC address, the next hop's MAC address, the public network label, and the private
network label into the packet and then forwards the packet to the core network according to
the next hop's MAC address.
2. After receiving the packet, the core network encapsulates the packet with the new public
network label and the MAC address of the new next hop device, and then forwards the packet
to the specified PE accordingly.
3. The PE sends the packet to the right CE through the AC according to the private network label.
L2VPN Manager Overview 9