28299-BRF-001-A Datasheet, PDF (1/4 Pages) M/A-COM Technology Solutions, Inc. – Automatic Protection Switching Controller Software

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A CONEXANT BUSINESS
Automatic Protection Switching Controller Software
CX28299
Complete APS Solution for Linear 1+1,
1:n and UPSR
Automatic Protection Switching (APS) is a feature for
SONET equipment that is used to improve the availability
and reliability of transport systems by switching to a
standby facility when failures occur. The Mindspeed APS
Controller complies with the GR-253-CORE standards
identified for two varieties of linear switching (1+1 and
1:n) as well as a ring switching topology known as SONET
GR1400 Unidirectional Path Switched Rings (UPSR). This
single package offers a portable solution to make imple-
mentation of Linear 1+1, 1:n and (UPSR) architectures
simple and quick. The APS Controller can also be distrib-
uted to support card level protection.
APS Controller
The APS Controller is operating system (OS)- and hard-
ware independent software with well-defined interfaces
that allow easy integration with system software. The
APS Controller consists of an application interface for
users’ applications and network management, a SONET
driver interface for interacting with a SONET device, and
a bridging/switching interface for switching over the
standby line. The APS software works with Mindspeed’s
TAP driver software to provide a complete PHY solution.
> KEY FEATURES
> 1+1 and 1:n Linear
Architectures
> UPSR support
> Distributed processor support
> GR-253 and G.783 Annex
ACompliant
> ANSI-C Source Code
> Works with Mindspeed TAP
software drivers to provide
complete solution
> Portability across Operating
Systems and hardware
platforms
APS State Machine
At the heart of the APS Controller is a state machine
that handles the signaling and the state transitions
based on incoming APS messages. The APS message for
Linear configurations consists of the combination of K1
and K2 bytes of the SONET overhead frame. The K1 and
K2 are used to coordinate bridging and switching action
with the far end.
For UPSR architectures, path layer indications are
detected locally by the APS controller and used to switch
to the ring that exihibits the best performance.
Network Management and Configuration
The APS Controller’s application interface lets users
employ existing network management software with the
Controller to provide protection switching messages and
statistic retrieval. The APS is highly configurable through
the application programming interface (API).
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