This survey paper discuss the security challenges in IoT network. IoT is hot research topic in between researchers. In the era of digital media IoT play an important role of information servers and data warehouses. IoT network are used in different cities of smart city network. That's why the security of the IoT network is also a big task. There are many loop holes available in IoT based security network. In this survey paper discuss the security aspects in the IoT networks. Also discuss the different researches previous work and previous work in IoT security. This survey analyzes existing protocols and mechanisms to secure communications in the IoT, as well as open research issues. We analyze how existing approaches ensure fundamental security requirements and protect communications on the IoT, together with the open challenges and strategies for future research work in the area. This is, as far as our knowledge goes, the first survey with such goals.

In this paper, present an improved transmission control protocol. For IoT devices. Currently there are different protocols are exist based on user data gram approach. Similarly TCP is also worked alone, In this present work proposed and improved transmission control protocol that is the hybrid concept of TCP and UDP on IPV6 platform. In the ITCP protocol TCP is used for link connection between two devices and UDP is used for the data sending. On the basic on this proposed new protocol that shows good improved result the transmission time, throughput, packet delivery ratio and other parameters as compare to other IoT protocol present in the IoT. For the simulation of proposed ITCP protocol used JAVA platform. Also compare the proposed result with different protocols. KeywordsComputational time, throughput, packet delivery ratio (PDR), packet loss, transmission control protocol (TCP) and User data gram protocol (UDP).