I suggest you to look for "research challenges" articles, such as:
Internet of things: Vision, applications and research challenges
The internet of things: A survey
Opportunistic IoT: Exploring the harmonious interaction between human and the internet of things
Internet of things strategic research roadmap
I've found all these articles on Google Scholar.
By the way, IoT is a research universe. You must refine what you are into: networking, integration protocols, hardware, human-computer interaction, polices ...
Good luck in your master thesis. And let me know the advances you are having.
One area you might like to consider is the concept of IoT security. IoT is a challenging area, with plenty of scope to develop something interesting for your research. I have attached a list of 19 recent publications, and I have a few of my own coming out during the next six months. Please feel free to download all my security research papers. These are mostly geared towards cloud, which is a fundamental enabler of IoT and Big Data technology, so they will give you some really useful background on many of the security issues you will face.
Thank you Joao Soares& Bob Duncan & Saad Motahhir for your answer and take your times to answer and guide me through this,I will look at the articles you mentioned and Bob published .