30 Sun Crypto Accelerator 4000 Board Installation and User’s Guide • May 2003
Interrupt Parameters
TABLE3-7 describes the receive interrupt blanking values.
Random Early Drop Parameters
These parameters provide the ability to drop packets based on the fullness of the
receive FIFO. By default, this feature is disabled. When FIFO occupancy reaches a
specific range, packets are dropped accordingto the preset probability. The
probabilityshould increase when the FIFO level increases. Control packets are never
dropped and are not counted in the statistics.
TABLE3-7 RX Blanking Register for Alias Read
FieldName Values Description
rx-intr-pkts 0 to 511 Interrupts after this numberof packets have arrived
since the last packet was serviced. A value of zero
indicates no packet blanking. (Default=3)
rx-intr-time 0 to 524287 Interrupts after 4.5 microseconds(usecs) have elapsed
since the last packet was serviced. A value of zero
indicates no time blanking. (Default=3)
TABLE3-8 RX Random Early Detecting 8-Bit Vectors
FieldName Values Description
red-dv4to6k 0 to 255 Random early detection and packet drop vectors for
whenFIFO threshold is greater than 4096 bytes and less
than 6,144 bytes. Probabilityof drop can be
programmedon a 12.5 percent granularity. For
example, if bit 0 is set, the firstpacket out of every
eight will be droppedin this region. (Default=0)