The following GFP encapsulation are possible with ESW4_E14:
•
Mapping Ethernet MAC frames into Lower Order SDH VC12-Xv (X = 1...63)
•
Mapping Ethernet MAC frames into Lower Order SDH VC3-Xv (X = 1...21)
•
Mapping Ethernet MAC frames into Higher Order SDH VC4-Xv (X = 1...7)
LAPS encapsulation is implemented according to ITU-T X.86.
Advanced rate control
The ESW4_E14 option card supports advanced rate control in the ingress and egress
direction which enables users to set a strict traffic limit (PIR), in combination with a
hold-off mechanism: Excess traffic is held off until the ingress or egress buffer
overflows. In case the ingress buffer fills above a certain threshold, pause messages are
sent in the reverse direction to hold off further traffic. This behaviour improves the
TCP throughput.
Provisioning Committed Burst Size (CBS)
The Flow Profile containing the parameters that define the QoS regime and is applied
to a flow contains a user provisionable entry for the Committed Burst Size (CBS).
This entry describes the number of octets that may be
″
bursted
″
before a frame is no
longer considered part of the
″
Committed Rate
″
. The CBS rate can be provisioned in
kbytes between 1 and 25000 or as a time constant relative parameter to CIR: 10 or 110
ms.
Provisioning Peak Burst Size (PBS)
The Flow Profile containing the parameters that define the QoS regime and is applied
to a flow contains a user provisionable entry for the Peak Burst Size (PBS).
This entry describes the number of octets that may be
″
bursted
″
before a frame is no
longer considered part of the
″
Peak Rate
″
. The PBS rate can be provisioned in kbytes
between 1 and 25000 or as a time constant relative parameter to CIR: 10 or 110 ms.
QoS features
The ESW4_E14 option card supports the following QOS features:
•
Two rate three color marker (RFC 2697, RFC 2698, and MEF 10) per flow
(switchable color aware/color unaware)
Based on provisioned threshold rates (CIR and PIR):
–
Red - The frame is dropped
–
Yellow - The Dropping Precedence of the frame is set to high
–
Green - The Dropping Precedence of the frame is set to low
•
Over subscription (2 levels of Dropping Precedence) and strict policing modes
Based on queue filling and the Dropping Precedence, frames can be dropped to
avoid congestion
–
A queue will allow fewer “yellow” frames than “green” frames
•
4 traffic classes, 4 egress queues per port
Product description
Introduction
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365-312-847R4.0
Issue 4, November 2006
Lucent Technologies - Proprietary
See notice on first page
2-25
