ibm3206k0424 ETC-unknow, ibm3206k0424 Datasheet - Page 39

• Manufacturer Part Number: ibm3206k0424
• Description: Ibm Processor For Network Resources
• Manufacturer: ETC-unknow

IBM3206K0424
Preliminary
IBM Processor for Network Resources
Receive Path
As cells arrive, they pass from LINKC to REASM. REASM uses a portion of the ATM header to look up the
LCD address for this cell. The LCD address is then passed to RAALL. RAALL reads the receive portion of the
LCD, and then processes the cell based on the LCD information. For example, the LCD specifies what AAL to
use and maintains the current reassembly state. Using the current reassembly state, the cell data is written to
Packet Memory. While the data is written to Packet Memory, other functions such as CRC generation and
verification are performed in parallel. If a packet is complete, all trailer verification is performed. If the packet
is good, an event is placed on a receive queue in the RXQUE entity. For error scenarios, see Receive
Queues (RXQUE) on page 366. At this point, software can dequeue the packet event from RXQUE using the
dequeue operation. It can then examine headers, DMA the data into user space, and perform TCP check-
sums. When these actions are complete, the buffer is returned to the IBM3206K0424 by performing a
POOLS-free buffer operation.
pnr25.chapt01.01
Receive Path
August 14, 2000
Page 39 of 676