Determining space requirements for alias index entries

An exact formula for calculating the space required for alias entries cannot be derived due to index block compression, and the mechanics of the higher level index blocks. The following is an approximate formula for space taken up in the alias index block sequence set (level 1) by an index entry:

AIE = 16 + (N * (2 + BPL)) + AKL

Where:

		Space taken up
AIE	=	Alias index entry length
N	=	The number of base profile names. Most aliases are only allowed 1 base profile association.
BPL	=	Base profile name length. The base profile is named in the alias index entry. Because the base profile is a user or group profile, valid BPL values are between 1 and 8.
AKL	=	Alias index entry, key length. The first 3 bytes are template number, segment number, and field number. Additional bytes of the alias index key are taken up by the alias value. These lengths vary according to each alias field.