Abstract: A multi-table-based grant generator in accordance with the present invention solves the issue of bandwidth granularity, while maintaining the simplicity of a table approach. The present invention grant generator provides grants of fine granularity for regulation of upstream transmission of cells in an ATM PON. Multiple grant tables having differing bandwidth granularities are linked together through a simple grant distribution mechanism. The grant tables and grant distribution mechanisms can be recursively linked to achieve a number of different granularities. The grant generator of the present invention is based on multiple grant tables with a combination of multiplexers, dividers, and address counters. The grant generator provides both larger and smaller bandwidths for data grants as well as PLOAM grants without large size grant tables. In one exemplary embodiment of the present invention, improved granularity is achieved, where a first grant table is used for one size of bandwidth grant, e.g.