PMC-Sierra PM5349 manual Receive Path Overhead Processor Rpop, Pointer Interpreter

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PMC-Sierra, Inc.

S/UNI-QUAD

DATASHEET

PM5349 S/UNI-QUAD

PMC-971239

ISSUE 6

SATURN USER NETWORK INTERFACE (155-QUAD)

 

 

 

10.5 Receive Path Overhead Processor (RPOP)

The Receive Path Overhead Processor (RPOP) provides pointer interpretation, extraction of path overhead, extraction of the synchronous payload envelope, and path level alarm indication and performance monitoring.

10.5.1Pointer Interpreter

The Pointer Interpreter interprets the incoming pointer (H1, H2) as specified in the references. The pointer value is used to determine the location of the path overhead (the J1 byte) in the incoming STS-3c (STM-1) stream. The algorithm can be modeled by a finite state machine. Within the pointer interpretation algorithm three states are defined as shown below:

NORM_state (NORM)

AIS_state (AIS)

LOP_state (LOP)

The transition between states will be consecutive events (indications), e.g., three consecutive AIS indications to go from the NORM_state to the AIS_state. The kind and number of consecutive indications activating a transition is chosen such that the behavior is stable and insensitive to low BER. The only transition on a single event is the one from the AIS_state to the NORM_state after receiving a NDF enabled with a valid pointer value. It should be noted that, since the algorithm only contains transitions based on consecutive indications, this implies that, for example, non-consecutively received invalid indications do not activate the transitions to the LOP_state.

Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use

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PMC-Sierra PM5349 manual Receive Path Overhead Processor Rpop, Pointer Interpreter