Internet of 'things (IoT) allows people and objects to be connected anytime, anywhere, in any way/shape and function that can build a dynamic network. IoT is a critical enabling technology for smart home facilities like smart locks, automatic light control, smoke detection, temperature monitoring, etc. With the adoption of these systems, security and privacy have come up as the primary concerns. Due to the security threats, developing such a system that can smartly identify and restrict the people coming within the house premises is needed. Although these systems exist in the modern world where the intruder's entry is based on authentication, these systems provide security until the intruder enters the house's premises. We propose a framework for a smart door chain system (SDCS) to ensure the home's security even after the visitor enters the house to overcome this security issue. The proposed framework provides access to visitor's categories that are family, friend, and unknown. The SDCS has a synchronized chain of doors that are unlocked accordingly after the authentication of a visitor. By implementing the proposed framework, it is determined that the security of the house increases compared to the security provided by the previous automated systems. The proposed SDCS framework is beneficial, especially for old ages, disabled and working people if any nasty situation is raised at home in their absence.