PM5364 pmc-sierra, PM5364 Datasheet - Page 126

• Manufacturer Part Number: PM5364
• Description: Tupp 2488 Assp Telecom Standard
• Manufacturer: pmc-sierra

10.6.8
Proprietary and Confidential to PMC-Sierra, Inc., and for its customers’ internal use.
Document No.: PMC-2011334, Issue 7
Incoming STS-1 (VC3/VC4) path overhead bytes may be optionally transferred to the outgoing
stream on a best effort basis. Error-free transfer cannot be guaranteed as the incoming and
outgoing payload frame rates may differ resulting in an excess or deficit of incoming POH bytes
on the incoming stream relative to the outgoing stream. Path overhead pass-through is disabled
for any STS-1 configured to process a C3 mapped into a VC3.
The VTPA provides optional squelch control on a tributary multiframe (H4). The multiframe
alignment sequence can be reset to all ones. Normal sequencing resumes when the squelch
control is removed.
The VTPA regenerates transport overhead bytes (except A1/A2/H1/H2 bytes), fixed stuff bytes
and tributary V4 byte with all-zero pattern.
SONET/SDH Virtual Container Aligner (SVCA_R)
The SVCA_R aligns the transport overhead of an STS-12/STM-4 stream to a new reference
signal. When used in the SONET/SDH receive path, it aligns the transport overhead to an
transport frame reference (J0). The alignment is accomplished by recalculating the STS payload
pointer value based on the offset between the transport overhead of the incoming and outgoing
streams. It inserts valid high order pointer bytes (H1, H2), framing bytes (A1, A2), and
otherwise all-zero transport overhead bytes.
Multiple SVCAs can be used to process higher concatenated payloads (STS-48c/VC4-16c). An
STS-48c/VC-4-16c is processed by four SVCA. The first SVCA is master and the three others
are slaves.
Outgoing pointer justification events are indicated on two separate outputs. A slave SVCA uses
one of these outputs to perform the required justification when a concatenated STS-48c/STM-
16c is processed. The other set of outputs can be used for performance monitoring. Excessive
pointer justification events may indicate network synchronization failure. Finally, the SVCA
provides pointer justification performance counters for each path.
The SVCA aligns the synchronous payload of any legal mix of STS-1/3c/12c (VC-3/4/4c). The
STS (VC) payloads are independently floating inside the STS-12 (STM-4) transport frame. The
SVCA must align each one independently.
The SVCA provides support for a VC4 virtual container carrying TUG-3 tributary data. The
SVCA removes TUG-3 fixed stuff columns (#1, #2, #3, #4, #5, and #6) and adds VC-3 fixed
stuff columns (#30 and #59) on the system side-outgoing stream.
External PAIS insertion is provided to insert path alarm indication signal (AIS) in the outgoing
SONET/SDH stream on a per path basis. Also, internal events (FIFO overflow or underflow)
optionally cause path AIS insertion.
The SVCA supports a transparent bypass mode. In this case, the SVCA does not buffer the input
stream nor realign it. The SVCA simply clocks out the input data on the next output clock rising
edge.
TUPP™ 2488 ASSP Telecom Standard Product Data Sheet
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