This paper studies the problem of the implementation of distributed computing applications in local area networks. We propose a novel Dynamical Wavelength Scheduled Wavelength Division Multiplexing Passive Optical Network (WDM-PON) architecture, in which the number of the available upstream wavelength channels is greatly less than that of optical network units (ONU). And we experimentally demonstrate the feasibility of the proposed WDM-PON, which enables dynamically scheduling upstream data in the time division multiplexing (TDM) and WDM scheme from ONU to optical line terminal (OLT). The Time-Wavelength Co-Allocation (TWCA) Problem is defined in the proposed WDM-PON architecture to aggregate large files for distributed computing applications and three scheduling algorithms are presented to solve this problem. The significant improvement compared with the conventional TDM-over-WDM PON is illustrated through simulations.