Internet of things (IoT) devices are resource-constrained devices with limitations such as low computation power, low communication capabilities, low bandwidths, high latency and short lived power. Therefore, securing the communication among these devices is a key challenge for various sensitive applications. However, conventional encryption and decryption algorithms, known as ciphers, cannot be implemented because of their inherent complexities of implementation and power requirements. One of the promising options available is to implement light-weight ciphers for these resource constrained devices. Moreover, the choice of lightweight encryption tool has great dependency on the type of IoT devices being used in an application. In this paper, a lightweight cellular automata (CA) based cipher, named as Lightweight CA Cipher (LCC) has been proposed for IoT applications. In the proposed method, encryption is done at the perception layer, where the sensor nodes are deployed and decryption is done at the network layer where gateway devices are installed. Experimental results show that the proposed method is efficient than some of the existing ciphers like DES, 3DES when randomness, execution time and implementation simplicity are considered as prime requirements. This cipher passes the randomness tests as prescribed by National Institute of Standards and Technology (NIST), and it also passes all the DIEHARD tests and it establishes the security feature of LCC. Though it is specially designed for resource-constrained environments, it can be scaled up for a large number of sensor nodes.