  Single photon source represent a fundamental building block for optical
implementations of quantum information tasks ranging from basic tests of
quantum physics to quantum communication and high-resolution quantum
measurement. In this paper we investigate the performance of a multiplexed
system based on asymmetric configuration of multiple heralded single photon
sources. {To compare the effectiveness of different designs we introduce a
single-photon source performance index that is based on the value of single
photon probability required to achieve a guaranteed signal to noise ratio.} The
performance and scalability comparison with both currently existing
multiple-source architectures and faint laser configurations reveals an
advantage the proposed scheme offers in realistic scenarios. This analysis also
provides insights on the potential of using such architectures for integrated
implementation.
