Extensive Fault Tolerance; Buffer And Queue Management - Avaya Cajun P882 User Manual

Extensive Fault Tolerance

Buffer and Queue Management

Avaya P550R, P580, P880, and P882 Multiservice Switch User Guide, v5.3.1
All multiservice switches are designed to function as backbone
switches. You can install each switch in your network's core without
creating a single point of failure.
Extensive fault tolerance features include:
N+1 power. Power supplies share the power supply load. If
one fails, the remaining supplie(s) assume the load
automatically and the switch management system warns of
the failure.
Hot-swappable fans and modules - Each fan and module can
be changed from the switch front panel, without powering
down the switch.
Redundant switch links (using spanning tree and link
aggregation groups).
Front-loadable cables, modules, power supplies and fans.
Redundant switch element and switch controller modules
(fault-tolerant switches only).
Buffer and queue management relieves congestion in a network.
Adding gigabit speeds to existing networks means that there can be
a huge disparity between link speeds. For example, anything more
than a 1-percent load on a gigabit link could easily overwhelm a 10
Mb/s Ethernet link.
Each switch employs the following buffer and queue management
techniques:
Configurable active backpressure:
Half-duplex ports use active backpressure to jam input
—
ports when their frame buffers are full.
Full-duplex links use IEEE 802.3z pause control frames to
—
pause traffic when buffers are full.
Packed frame buffers for optimal memory utilization. The
memory management allows virtually 100% utilization of
buffer memory.
Introduction
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