Supporting Quality Of Service Features - Extreme Networks BlackDiamond 6800 MPLS Installation And User Manual

Source IP
network
Figure 3-2: LSR types
The functions of the LSR types are described in Table 3-2.
Table 3-2: LSR Functions
LSR
Ingress LER
Intermediate LSR
Egress LER

Supporting Quality of Service Features

Quality of Service (QoS) LSP support is an important attribute of MPLS. MPLS supports
the Differentiated Services (DiffServ) model of QoS. The DiffServ QoS model is
supported by mapping different traffic classes to different LSPs, or by using the EXP
bits in the MPLS shim header to identify traffic classes with particular forwarding
requirements.
MPLS Module Installation and User Guide
Ingress
LSR
LER
MPLS cloud
Function
Inserts one or more labels into packets transmitted onto an
LSP.
Forwards packets via label swapping.
Removes the last label(s) before forwarding packets received
from an LSP.
LSP A
LSP B
Egress LER
for LSP B
Egress LER for LSP A
Overview of MPLS
LSR for
LSP A Destination
IP network
for LSP B
Destination
IP network
for LSP A
MPLS_12
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