This attribute is obsolete. Please refer to the Override component
for the new attribute.
This attribute specifies the initial VPI of the optional Programmable
VCC Space.
If numNonZeroVpisForVccs is 0 the Programmable VCC Space
does not exist. If numNonZeroVpisForVccs is greater than 0 the
Programmable VCC Space exists and covers the VPI values ranging
from firstNonZeroVpiForVccs to (firstNonZeroVpiForVccs +
numNonZeroVpisForVccs - 1).
The initial VPI of the Programmable VCC Space must either be 1
or a non-zero multiple of 16.
The VCC Space as a whole must adhere to the guidelines laid down
in the description of the AtmConnMappingVccProv group.