pxf4336 Infineon Technologies Corporation, pxf4336 Datasheet - Page 65

• Manufacturer Part Number: pxf4336
• Description: Abm Premium Atm Buf Fer Manager
• Manufacturer: Infineon Technologies Corporation

3.4.1
3.4.1.1
The basic function of the Buffer Manager (BM) is to decide whether an arriving cell is
granted access to the shared buffer or is discarded. This is done by running the Cell
Acceptance Algorithm (CAA) (see
accessed by the CAA are summarized in
Figure 3-15 Buffer Manager Tables
More generally, the buffer manager allocates the buffer resources needed to fulfill the
specific service guarantees of individual connections.
In a first step when receiving a cell, the Local Connection Identifier (LCI) that was
previously assigned by the Header Translation (see
corresponding Queue Identifier (QID). The QID represents the logical queue in which the
cell will be stored upon acceptance and serves as an index for subsequent table lookups.
In particular, the Scheduler Block and the Traffic Class of the received cell is identified
with the Scheduler Block Identifier (SBID) and the Traffic Class Identifier (TCID)
respectively.
With any incoming cell, the Cell Acceptance Algorithm (CAA) can access the current
buffer status information containing counters, thresholds and flags. Based on this data,
the cell is either discarded or accepted. The respective counters are updated
appropriately.
Data Sheet
Buffer Manager
Functional Overview
LCI
Local Connection
Connection Specific
Identifier Table
Global Buffer Data
16384 entries
(up / down)
Data
QID
Queue Configuration Table
Queue Specific Data
2 x 8192 entries
Chapter
Figure
65
3.4.1.7). The buffer manager tables
Cell Acceptance Algorithm
3-15.
SBID
TCID
Scheduler Block Occupancy Table
Figure
2 x 128 entries
Specific Data
Scheduler
Functional Description
3-13), is mapped to a
Traffic Class Table
2 x 16 entries
Queue / Traffic
Class Specific
Data
PXF 4336 V1.1
2001-12-17
ABM-P