Qos Atm Traffic Descriptor Profiles - Alcatel-Lucent 7450 Quality Of Service Manual

Any discard decision are performed exclusively at the packet level where the context for the
frame forwarding class and for the 802.1p bit mapping to a forwarding class is known. When
a per-VC queue backs up, a back pressure scheme is applied such that the frames are held in
the per-forwarding class packet queues dedicated to this VC.
This hierarchical scheduling of frames and cells of a given VC terminating on a VPLS
instance provides the flexibility to apply policing and shaping on a per-forwarding class basis
for the Ethernet frames of each VC as well as the option to shape the aggregate cell flow into
the ATM VC back into the customer site.
This QoS model is applied to all router services which include an ATM SAP (VLL, VPLS,
IES and VPRN).
ATM Service Categories
The router supports the following service categories:
ATM Traffic Descriptors and QoS Parameters
The router supports the following traffic descriptors for ATM.
Service Category
CBR
Rt-VBR and nrt-VBR
UBR/UBR+MIR
Quality of Service Guide
• CBR - Constant Bit Rate
• Rt-VBR - Real-Time Variable Bit Rate
• nrt-VBR - Non Real-Time Variable Bit Rate
• UBR/UBR+MIR - Unspecified Bit Rate with Minimum Cell Rate. UBR is a special
case of UBR+MIR where MIR=0.
Table 48: ATM Traffic Descriptors
Traffic Descriptors
P0_1 PIR in Kbps (applies to CLP=0 & CLP=1 flows)
P0_1and S0_1 PIR in Kbps (applies to CLP=0 & CLP=1 flows) SIR
in Kbps (applies to CLP=0 & CLP=1 flows)
MBS in cells (applies to CLP=0 and CLP=1 flows)
P0_1 and S0 PIR in Kbps (applies to CLP=0 & CLP=1 flows)
SIR in Kbps (applies to CLP=0 flow only)
MBS in cells (applies to CLP=0 flow only)
P0_1 PIR in Kbps (applies to CLP=0 & CLP=1 flows)
MIR in Kbps (applies to CLP=0 & CLP=1 flows)

QoS ATM Traffic Descriptor Profiles

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