HPE FlexNetwork 5510 HI Series, Руководство по настройке Mpls

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Node protection —The PLR and the MP are connected through a device and the primary
CRLSP traverses this device. When the device fails, traffic is switched to the bypass tunnel. As
shown in
Figure 24 , the primary CRLSP is Router A—Router B—Router C—Router D—Router
E, and the bypass tunnel is Router B—Router F—Router D. Router C is the protected device.
This mode is also called next-next-hop (NNHOP) protection.
Figure 24 FRR node protection
DiffServ-aware TE
DiffServ is a model that provides differentiated QoS guarantees based on class of service. MPLS TE
is a traffic engineering solution that focuses on optimizing network resources allocation.
DiffServ-aware TE (DS-TE) combines DiffServ and TE to optimize network resources allocation on a
per-service class basis. DS-TE defines different bandwidth constraints for class types. It maps each
traffic class type to the CRLSP that is constraint-compliant for the class type.
The device supports these DS-TE modes:
•
Prestandard mode —Proprietary DS-TE mode of Hewlett Packard Enterprise.
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IETF mode —Complies with RFC 4124, RFC 4125, and RFC 4127.
Basic concepts
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CT —Class Type. DS-TE allocates link bandwidth, implements constraint-based routing, and
performs admission control on a per class type basis. A given traffic flow belongs to the same
CT on all links.
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BC —Bandwidth Constraint. BC restricts the bandwidth for one or more CTs.
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Bandwidth constraint model —Algorithm for implementing bandwidth constraints on different
CTs. A BC model comprises two factors, the maximum number of BCs (MaxBC) and the
mappings between BCs and CTs. DS-TE supports two BC models, Russian Dolls Model (RDM)
and Maximum Allocation Model (MAM).
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TE class —Defines a CT and a priority. The setup priority or holding priority of an MPLS TE
tunnel for a CT must be the same as the priority of the TE class.
The prestandard and IETF modes of DS-TE have the following differences:
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The prestandard mode supports two CTs (CT 0 and CT 1), eight priorities, and up to 16 TE
classes. The IETF mode supports four CTs (CT 0 through CT 3), eight priorities, and up to eight
TE classes.
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The prestandard mode does not allow you to configure TE classes. The IETF mode allows for
TE class configuration.
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The prestandard mode supports only RDM. The IETF mode supports both RDM and MAM.
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A device operating in prestandard mode cannot communicate with devices from some vendors.
A device operating in IETF mode can communicate with devices from other vendors.
Router A Router B Router C Router D
Router F
PLR MP
Router E
Primary CRLSP
Bypass tunnel