Abstract— With the arrival of smart homes, smart cities, and
smart everything, the web of Things (IoT) has emerged as a
neighborhood of incredible impact, potential, and growth, with
Cisco Inc. predicting to possess 50 billion connected devices by
2020.However, most of those IoT devices are easy to hack and
compromise. IoT devices are limited in compute, storage, and
network capacity. So that they are easier to attack than other
devices like smart phones, tablets, or computers. This paper
proposes an in depth overview of the IoT technology and its
varied applications in life saving, smart cities, agricultural,
industrial etc. Finally some major problems with future
research in IoT are identified and discussed in brief.
Index Terms—Architecture, Applications, Challenges IoT
and Open Issues.