The pethPsePortGroupIndex is imported from the IETF Power MIB
and uniquely identifies the group containing the port to which
power ethernet PSE is connected. Group means (box in the stack,
module in a rack).
The pethPsePortPowerIndex is imported from the IETF Power MIB
and uniquely identifies the power ethernet PSE port within group
pethPseGroupIndex to which the power Ethernet PSE entry is
connected. This value will match the local port number on a
switch.