The integration of transportation systems is a very important issue within our society. In order to realize more secure and efficient systems, an integrated system needs to be developed that is decentralized, stable and highly automated. In previous papers we have proposed a three layer object model (3LOM) as the base architecture for the integration of transportation systems. This a per describes the design of the physical input/output sub-system in the bottom layer of the architecture and how to implement this layer from the technical perspective. This layer is primarily responsible for data acquisition, filtering and transmission of data to the middle layer and related control centers. Local knowledge is organized to be used to perform controlling functions within a localized environment. This paper is an important contribution to design the logical view of the bottom layer as an important step to develop the proposed integrated transportation system as our ultimate aim.