Alcatel-Lucent 1643 AMS Applications And Planning Manual page 234

Ethernet Overview
2. Oversubscription mode (CIR < PIR)
The oversubscription mode allows users to burst their data flow to a maximum
available WAN bandwidth at a given instance. When PIR is set equal to the maximum
of the physical network port bandwidth, then a user is allowed to send more data than
the specified CIR. The additional data flow above CIR has a higher dropping
probability.
The following two cases can be differentiated in oversubscription mode.
Provisioning the rate control mode
The desired rate control mode can be chosen by enabling/disabling oversubscription
support (QoS_osub = enabled/disabled), and by setting the CIR and PIR values. CIR
and PIR values can be set by means of QoS profiles (see
provisioning" (p.
The setting of the QoS_osub configuration parameter in combination with the
relationship between CIR and PIR determines which rate control mode becomes
effective. If, for example, oversubscription support is enabled, and the relationship
between CIR and PIR is CIR = PIR ≤ MAX, then the rate controller is operated in
strict policing mode.
Important!
1. Which of the rate control modes can actually be configured depends on the
2. As a general rule it is recommended to use the oversubscription mode for
....................................................................................................................................................................................................................................
11-58
0 < CIR < PIR = MAX
0 kbit/s
green
0 = CIR < PIR < MAX
(CIR)
0 kbit/s
yellow
11-64)).
mode of operation (see
TCP/IP applications, especially in case of meshed or ring network topologies
where multiple end-users share the available bandwidth.
Alcatel-Lucent - Proprietary
CIR
yellow
PIR
red
"Quality of Service configuration options" (p.
See notice on first page
Classification, queueing and scheduling
Information
rate
Information
rate
"Quality of Service
11-52)).
365-312-801R7.2
Issue 3, May 2007