S/UNI®-ATLAS-3200 Telecom Standard Product Data Sheet
Preliminary
Table 27 Per-PHY and per-VC Non-Compliant Cell Counting PHYVCCount=1
PHYVCCount=1
Per-VC Policing
Compliant
Non-Compliant
Per-PHY Policing
Compliant
No update.
Update per-VC non-compliant
counts
Update per-PHY non-
compliant counts.
Non-Compliant
Update per-VC non-compliant Update per-VC non-compliant
counts.
counts.
Update per-PHY non-
Update per-PHY non-
compliant counts
compliant counts.
10.7.3 Guaranteed Frame Rate Policing
The S/UNI-ATLAS-3200 supports Guaranteed Frame Rate (GFR) policing in accordance with the
ATM Forum Traffic Management Specification 4.1. A total of four policing actions are observed
for GFR policing. They are: Maximum Frame Length (MFL) conformance test, Peak Cell Rate
(PCR) test, Minimum Cell Rate (MCR) conformance test, and the CLP Conformance test. When
GFR policing is enabled, the GFR policing algorithm is enabled. The conformance tests are
evaluated sequentially, in the following order:
1. MFL conformance test. When an End Of Message cell in a packet is received, the Remaining
Frame Count field of the VC Table is loaded, after testing for MFL conformance with the
current value, with the value programmed in the Maximum Frame Length field in the VC
Table. The Remaining Frame Count is then decremented with each cell received in the new
frame. If this value reaches zero before an End Of Message cell is received, the remainder of
the frame is discarded (the EOM cell is identified by having an SDUTYP equal to logic 1).
The MFL conformance test can be disabled by setting the MFL field in the VC table to all
ones.
2. PCR conformance test. This test is performed using GCRA1 in much the same manner as
normal cell policing. However, for compliance to the GFR specification, Action 1 must be
set to 11 (discard). If the PCR conformance test is deemed to be non-compliant, the
remainder of the cells in the current frame will be discarded. If the non-compliant cell is the
start of packet, then a complete packet discard is executed; if it is in the middle of a packet, a
partial packet discard is executed; if it is the end of a packet, it is discarded along with every
subsequent cell until a EOP is received which is not discarded.
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990553, Issue 4
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PMC [ PMC-SIERRA, INC ]
