HPE FlexNetwork 5510 HI Series, Руководство по настройке Mpls

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Assume that a VPN has 10 sites, and a PE assigns the first label block LB1/0/10 to the VPN.
When another 15 sites are added, the PE keeps the first label block and assigns the second
label block LB2/10/15 to extend the network. LB1 and LB2 are the initial label values that are
randomly selected by the PE.
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Route target —PEs use the BGP route target attribute (also called VPN target attribute) to
manage BGP L2VPN information advertisement. PEs support the following types of route target
attributes:

Export target attribute —When a PE sends L2VPN information to the peer PE in a BGP
update message, it sets the route target attribute in the update message to an export target.
L2VPN information includes the site ID, RD, and label block.

Import target attribute —When a PE receives an update message from the peer PE, it
checks the route target attribute in the update message. If the route target value matches an
import target, the PE accepts the L2VPN information in the update message.
Route target attributes determine from which PEs a PE can receive L2VPN information.
MPLS L2VPN network models
As shown in Figure 82 , this model connects two CEs through a PW on an MPLS or IP backbone.
Figure 82 MPLS L2VPN network model
To set up an MPLS L2VPN connection:
1. Set up a public tunnel to carry one or more PWs between PEs:
The public tunnel can be an LSP or MPLS TE tunnel.
If multiple public tunnels exist between two PEs, you can configure a tunnel policy to control
tunnel selection. For more information about tunnel policies, see "
Configuring tunnel policies ."
If a PW is established over an LSP or MPLS TE tunnel, packets on the PW have two labels. The
outer label is the public LSP or MPLS TE tunnel label that MPLS uses to forward the packet to
the peer PE. The inner label is the PW label that the peer PE uses to forward the packet to the
destination CE.
2. Set up a PW to connect customer networks:
PWs include static PWs, LDP PWs, BGP PWs, and Circuit Cross Connect (CCC) PWs.
To establish a static PW, configure the peer PE address, and the incoming and outgoing PW
labels for the PW on the two PEs. Static PWs consume a small amount of resources but have
complex configurations.
To establish an LDP PW, configure LDP and specify the peer PE address on the two PEs. LDP
defines a new FEC type named PW ID FEC for PEs to exchange PW-label bindings. The new
FEC type uses a PW ID and a PW data encapsulation type to identify a PW. The PW ID is the ID
of the PW between PEs. The PW data encapsulation type specifies the encapsulation type for
data transmitted over the PW, such as ATM, FR, Ethernet, or VLAN. PEs advertise the PW
label and PW ID FEC in label mapping messages to create a PW. Dynamic PWs have simple
configurations but consume more resources than static PWs.
CE 1 CE 2
PE 1 PE 2
Tunnel
PW
AC
AC
MPLS or IP backbone
Customer
network
Customer
network