The world of IoT existence is wholly being built on the communication and the interconnection

of things. Thing are nothing but edge devices which form the core element of IoT. From device

that have sensors in the farm that accept data as input to mobile in our pockets or to pacemakers

in the human heart are all innovative IoT devices that have today integrated in our lives. The idea

of designing an edge device would moves form a mechanical electrical machine or device to an

automatized electronic device. The electronic device soon transcended to use digital signal for its

working and were programmed to become smart devices. The electronic embedded device was

attached to the Internet thus developing the IoT network. IoT network has a continuum to data

transiting for one device to the next. Initially most of this data is open, unprotected and in the

clear text form since these devices are low level computing device with less power and memory.

The 6LoWPAN, NFC, RFID, Bluetooth, Wi-Fi or Zigbee were the types of the communication

used by them. It has been seen that in spite of various message protocols the basic commination

between the edge device has been the TCP and the UDP Communication protocol. The data was

always venerable to attack by malicious users. One of the solutions to provide protection to the

data was encryption of the plain text by encryption techniques before the data could be send for

one device to another. The research work is aimed to find out different was to improve and

implement security on the edge devices. This is done by creating a proposed prototype which

consist of raspberry pi that implemented smart homes. Experiments were carried out to check

communication between them, encrypting the data on transit, using symmetric and will a

lightweight cryptographic algorithm. The experiments use PRESENT and AES algorithms to

prove it. The system was breached to test the Ping of death and Smurf attack as DOS attack. The

Sniffing for the password was done by Wireshark that also helped in the monitoring of the

network. Thus, proving that encryption was a good solution for implementing security but the

network was venerable to DOS and DDOS attack. In the objective to improving the security and

privacy of edge device the research work opened avenue of using block chain a concept of

implementing security by constructing two contract that were linked with each other. One was a

device contract that would automatically get an agreement contract by a miner what could be

another device attached to it. It would act an authenticator and generate a key for the device. If

the device would want to communicate it would with the key. The transactions of the device and

well as the agreement were stored in the local store. The concept help to encrypt the data within

the transaction while the sender and the receiver addresses are hashed which is the security

benefits of the block chain.