Automatic Creation Of Sdps - Nokia 7302 Manual

Virtual Private LAN Service
5.10.5
When BGP AD is used for LDP VPLS and LDP is used as the transport tunnel there
is no requirement to manually create an SDP. The LDP SDP can be automatically
instantiated using the information advertised by BGP AD. This simplifies the
configuration on the service node. Enabling LDP on the IP interfaces connecting all
nodes between the ingress and the egress builds transport tunnels based on the best
IGP path. LDP bindings are automatically built and stored in the hardware. These
entries contain an MPLS label pointing to the best next hop along the best path
toward the destination.
When two endpoints need to connect and no SDP exists, a new SDP will
automatically be constructed. New services added between two endpoints that
already have an automatically created SDP will be immediately used. No new SDP
will be constructed. The far-end information is gleaned from the BGP next hop
information in the NLRI. When services are withdrawn with a BGP_Unreach_NLRI,
the automatically established SDP will remain up as long as at least one service is
connected between those endpoints. An automatically created SDP will be removed
and the resources released when the only or last service is removed.
5.10.6
The choice of manual or auto provisioned SDPs has limited impact on the amount of
required provisioning. Most of the savings are achieved through the automatic
instantiation of the pseudowire infrastructure (SDP bindings). This is achieved for
every auto-discovered VSIs through the use of the pseudowire template concept.
Each VPLS service that uses BGP AD contains the "pw-template-bind" option
defining specific layer 2 VPN parameters. This command references a "pw-template"
which defines the pseudowire parameters. The same "pw-template" may be
referenced by multiple VPLS services. As a result, changes to these pseudowire
templates have to be treated with great care as they may impact many customers at
once.
The Nokia implementation provides for safe handling of pseudowire templates.
Changes to the pseudowire templates are not automatically propagated. Tools are
provided to evaluate and distribute the changes. The following command is used to
distribute changes to a "pw-template" at the service level to one or all services that
use that template:
PERs-4# tools perform service id 300 eval-pw-template 1 allow-service-impact
If the service ID is omitted, then all services will be updated. The type of change
made to the "pw-template" will influence how the service is impacted.
1 Adding or removing a split-horizon-group will cause the router to destroy the
2 Changing parameters in the vc-type {ether|vlan} command requires LDP to
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Automatic Creation of SDPs

Automatic Instantiation of Pseudowires (SDP
Bindings)
original object and recreate using the new value.
re-signal the labels.
3HH-11985-AAAA-TQZZA
FD 100/320Gbps NT and FX NT IHub Services Guide
Issue: 13