Juniper JUNOSE 11.1.X - LINK LAYER CONFIGURATION 4-7-2010, Configuration Manual

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For more information, see chapter Configuring Layer 2 Services over MPLS in JUNOSe
BGP and MPLS Configuration Guide .
NOTE: The E120 and E320 routers do not support ATM over MPLS with VCC cell
relay encapsulation in the current release.
Traffic Management
The scheduling priority for traffic classes depends on the type of router that you
have. Table 3 on page 7 describes the scheduling priorities for each type of router.
Table 3: Scheduling Priorities for Traffic Classes
E120 and E320 routers
ERX7xx Models, ERX14xx
Models, or the ERX310
Broadband Services Router Scheduling Priority
(from Highest to
Lowest)
CBR The following traffic classes are
prioritized equally:
■
CBR
■
VBR-RT
1
VBR-RT The following traffic classes are
prioritized equally:
■
VBR-NRT
■
UBR with a peak cell rate
(PCR)
2
VBR-NRT UBR without PCR 3
UBR with or without PCR – 4
The level of support for traffic management depends on the specific I/O module or
IOA. See “Supported Features” on page 12.
Connection Admission Control
ATM networks use connection admission control (CAC) to determine whether to
accept a connection request, based on whether allocating the connection’s requested
bandwidth causes the network to violate the traffic contracts of existing connections.
CAC is a set of actions that the network takes during connection setup or
renegotiation.
The router supports CAC on PVCs on major ATM interfaces. This implementation of
CAC determines available bandwidth based on port subscription bandwidth. The
router maintains available bandwidth for each major ATM port. Bandwidth for VP
tunnels is included in CAC computations.
Overview
■ 7
Chapter 1: Configuring ATM