Description: 
The index of hpnicfSysBtmLoadTable. There are two parts for this
index depicted as follows:

31                  15                  0
+++++++++++++++++++++++++++++++++++++++++
+ physical index     +     random index +
( bit 16..31 )              ( bit 0..15 )
+++++++++++++++++++++++++++++++++++++++++

From bit0 to bit15 (two bytes), if the row is created by command
line, the value is determined by system, and if the row is created
by SNMP, the value is determined by users.

From bit16 to bit31 (two bytes) is the physical index the same as
the entPhysicalIndex specified in ENTITY-MIB.

If ENTITY-MIB is not supported, the value of this object is the
unit ID for XRN devices, 0 for non-XRN device which has only one
main board, the board number for non-XRN device which has multiple
main boards.