This paper presents a survey on the study of the scalable router and proposes a hierarchical model based on the study of the architecture and models of the scalable router. The model splits the scalable router into six layers from bottom to top, which are interconnection network and data switching layer, routing lookup layer, standard interface layer, distributed operating system layer, distributed routing behavior layer and single image management layer. The paper provides surveys on the research of each layer, and finally concludes and analyses the difficulties of current development of the scalable router.