Traffic engineering database – Brocade Multi-Service IronWare Multiprotocol Label Switch (MPLS) Configuration Guide (Supporting R05.6.00) User Manual
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Multi-Service IronWare Multiprotocol Label Switch (MPLS) Configuration Guide
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Traffic engineering database
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Change in the interface’s maximum available bandwidth or maximum reservable bandwidth.
•
Significant change in unreserved bandwidth per priority level, which can be either of the
following:
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For any priority level, the difference between the previously advertised, unreserved
bandwidth and the current, unreserved bandwidth exceeds five percent of the maximum
reservable bandwidth.
•
Any change when the total reserved bandwidth exceeds 95 percent of the maximum
reservable bandwidth.
In addition, IS-IS LSPs with TE extensions can be triggered by IS-IS (for example, when an
interface’s link state changes). Furthermore, when an interface is no longer enabled for MPLS, the
device stops sending out IS-IS LSPs with TE extensions for that interface.
Traffic engineering database
An LSR TED stores topology information about the MPLS domain. This topology information comes
from OSPF-TE LSAs and IS-IS LSPs with TE extensions that are flooded throughout the OSPF area or
IS-IS domain. When an LSR receives OSPF-TE LSAs or IS-IS LSPs with TE extensions from
neighboring LSRs, it places the traffic engineering information into its TED. In this way, each LSR in
the OSPF area builds an identical topology database that reflects the traffic engineering
constraints, bandwidth reservations, and administrative group memberships of the area’s
MPLS-enabled interfaces and the links that connect them.
The topology information in the TED is used by the CSPF process when it calculates
traffic-engineered paths for signaled LSPs, as the section
describes. The user can display the contents of an LSRs TED (refer to
“Displaying MPLS and RSVP information”
LSP attributes and requirements used for traffic engineering
In addition to the topology information in the TED, the device considers attributes and
requirements specified in configuration statements for the LSP. The following user-specified
parameters are considered when the device calculates a traffic-engineered path for a signaled
LSP:
•
Destination address of the egress LER
•
Explicit path to be used by the LSP
•
Bandwidth required by the LSP
•
Setup priority for the LSP
•
Metric for the LSP
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Whether the LSP includes or excludes links belonging to specified administrative groups
Refer to
“Configuring signaled LSP parameters”
for more information on how to set these
parameters.