This table contains extensions to the MIB II ifTable which contains the definitions of all interfaces. An ifTable entry may be a board or just a port on a board. Any ifTable entry can have an extension in the identIfExtensionTable. The corrsponding entry in that table will have the identIfIndex = ifIndex. Within the ifTable the presence of such an entry is indicated by setting the variable ifSpecific to the OBJECT IDENTIFIER value of identIfExtensionTable. Otherwise iFSpecific is set to {0 0}. The ifType - other - is used for all board types not envisoned by MIB II.