28229-DSH-001-B
Mindspeed Technologies
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CX28224/5/9 Data Sheet
Introduction to IMA
1.2.5
Performance Monitoring (PM)
This is the set of functions and capabilities necessary for a Network Element (NE) to
gather, store, and report performance data associated with its monitored digital
transmission entities In contrast with alarm/status indications, performance
parameters are quantitative, not binary, in nature. These performance parameters are
gathered over programmable, predetermined accumulation periods. The
CX28229TAP calculates these statistics over 15 minute intervals. The PM data is
available to the application grouped in a structure encompassing one of the two
accumulation sets: the current 15 minute interval or the previous 15 minute interval.
The PM subsystem uses the raw anomaly and defect information obtained by the FM
subsystem to calculate its performance statistics.
Upon initialization, the PM subsystem is basically disabled: none of the monitored
statistics are calculated.
1.2.6
Group State Machine
Overall management of each Group is the responsibility of the Group State Machine.
This actually involves three interrelated processes: the Group State Machine (GSM),
the Group Traffic State Machine (GTSM), and the Link Addition and Slow Recovery
(LASR) procedure. These three processes are used to ensure reliable transmission and
reception of ATM layer cells across all links in the Active state. This includes the
negotiation of group parameters (i.e., symmetry and M values), the bringing up of the
IMA group, and the graceful addition/recovery and deletion of links to and from the
group. The seven possible states are shown in
Table 1-6. Again, this will be covered in
more detail in
Chapter 3 and in the ATM standard on IMA.
Table 1-6. Group State Machine
State
Description
Not Configured
no groups configured
Start up
Waiting to establish communications with the other end
Start up Ack
Start Up acknowledge; has recognized the far end and waiting to enter the Insufficient links state
Config Aborted
results when the Far End doesn’t comply with the requested configuration parameters
Insufficient links
Both ends have accepted the group parameters and are waiting for the LSM to provide active links
Blocked
The host controller has inhibited the group (probably for maintenance reasons)
Operational
Fully operational and able to pass data