3Com S7906E - Switch, Руководство по настройке

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Cooperation of RSVP-TE and BFD: BFD is a fast detection mechanism, which can detect faults of
links or nodes timely. In this method, FRR can obtain the link status timely through BFD, so as to
implement fast switchover of links.
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RSVP hello: In this method, RSVP hello is enabled on each protected node and its neighbor nodes
along the primary LSP, so that a device periodically sends hello messages to its peer device on the
LSP. If a link or node fails, hello messages will be lost. If a device cannot receive hello messages
from its peer in three hello intervals, the hello mechanism concludes that a link failure occurs.
Hence, the hello mechanism is slower in link failure detection, compared with the other two
methods.
DiffServ-Aware TE
Diff-Serv 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 them to optimize network resources allocation at a per-service
class level. For traffic trunks which are distinguished by class of service, this means varied bandwidth
constraints.
Essentially, what DS-TE does is to map traffic trunks with LSPs, making each traffic trunk traverse the
constraints-compliant path.
DS-TE involves two concepts:
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Class type (CT): The set of traffic trunks crossing a link that is governed by a specific set of
Bandwidth constraints. CT is used for purposes of link bandwidth allocation, constraint based
routing, and admission control. A given traffic trunk belongs to the same CT on all links.
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Bandwidth constraints (BCs): Different BC models can be created to control CTs. A BC model is
broken down into maximum number of BCs (MaxBC), and mappings between BCs and CTs.
Currently, DiffServ-Aware TE is not supported.
Protocols and Standards
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RFC 2702 Requirements for Traffic Engineering Over MPLS
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RFC 3212 Constraint-Based LSP Setup using LDP
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RFC 2205 Resource ReSerVation Protocol
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RFC 3209 RSVP-TE: Extensions to RSVP for LSP Tunnels
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RFC 2961 RSVP Refresh Overhead Reduction Extensions
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RFC 3564 Requirements for Support of Differentiated Service-aware MPLS Traffic Engineering
MPLS TE Configuration Task List
Complete the following tasks to configure MPLS TE: