Juniper JUNOSE, Руководство по настройке

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egress queuing is based on the IP precedence value. This action takes place on
the egress line module.
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Plain VPN service—For CE-to-PE traffic, the VPN EXP bits are set to 000 when
the PE router pushes VPN stacked labels.
For PE-to-CE traffic, IP policy on the PE router resets the traffic-class/color
combination to the default value, best-effort/green, so that packets are queued
as best-effort. The IP precedence value is left unchanged.
In this example, the provider also offers an inter-AS VPN service. The provider's own
protocol traffic, for example, BGP signaling traffic such as update messages, is also
labeled, with the EXP bits set to the same value as the IP precedence.
The egress queuing of traffic as it leaves the provider is always based on either the
VPN EXP bits as received on the core side in inter-AS case, or the IP precedence
value in all other cases. It is acceptable that fabric queuing is based on the incoming
base label's EXP.
Figure 64: Differentiated Services over an MPLS Network
Differentiated Services Configuration Example
To configure the differentiated services described in this example:
1.
Create and attach an IP input policy for the QoS Internet service to CE interfaces
on the PE router for incoming traffic.
host1(config)# ip classifier-list prec0 ip any any precedence 0
host1(config)# ip classifier-list prec1 ip any any precedence 1
host1(config)# ip policy-list qos-service
host1(config-policy-list)# classifier-group prec0
host1(config-policy-list-classifier-group)# user-packet-class 0
host1(config-policy-list-classifier-group)# traffic-class class0
host1(config-policy-list-classifier-group)# color green
host1(config-policy-list)# classifier-group prec1
host1(config-policy-list-classifier-group)# user-packet-class 1
Example Differentiated Services Application and Configuration
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Chapter 3: Configuring MPLS