8 months ago


Lecture 1 on 12.9.2017,

Lecture 1 on 12.9.2017, 10-12, AS2: Introduction + C-RAN Today was the first lecture of the course. I was really excited since I am really interested in learning more about communication engineering. Today we talked about IoT, its applications and wireless LANs. A. Lesson learned I had already learnt what is IoT and what we can do with it. The difference between massive IoT and critical IoT was familiar but it was nice to hear about it again. Capillary network was a new concept for me. It is a local network that uses short-range radio-access technologies to provide local connectivity to things and devices. The challenges interfaces, legacy devices need to be supported and the scalability. LoRa Technology was also a new thing that I learnt. It offers a very compelling mix of long range, low power consumption and secure data transmission. The coverage is also larger than what existing cellular networks can offer. It supports two-way communication which makes it very functional. It was interesting to hear the differences between LoRa and Sigfox since I knew Sigfox from previous courses. B. Problems and open issues I understood what NB-IoT was all about but the physical downlink channels were hard to understand. There are different ways transmit the data. It is transmitted with frames and there are different frame sizes but it was difficult to form a big picture. Backscatter communications were also little bit hard to understand. It might be that I was tired since it was the end of the lecture but there was so many abbreviations and terms that the whole concept was hard to understand. C. Relevance The motivation at the start of the lecture was really inspiring. It gave me motivation since my short vacation had just ended. It was also good to hear something new about IoT and how it can be used. IoT will change our world step by step and I know that I will be involved in the developing. 2

Lecture 2 on 19.9.2017, 10-12, AS2: Software Defined Networking for Datacenters and the Wide Area Software Defined Networking for Datacenters and the Wide Area A. Lesson learned Today we talked about differences between IP and SDN. I had already learnt from previous courses that we have two modes of communication: - Connection-less (significant addresses appear in each packet) and connection-oriented (no addresses in packages) but the terms were new for me. IP in public networks is problematic since there are more and more mobile devices and content and it is flooding our servers. I have seen this phenomenal for example in festivals where many people are in same place and mobile network has become very slow. I learnt that we have different states in networks: network and flow state. Network state can be for example routing table and flow state can be binding state. From IP to SDN process was new for me. IP routing was familiar to me. For example, I knew that IP has a distributed control so each node is autonomous. SDN was new for me, actually the whole concept was new for me. SDN is a new emerging networking paradigm for the Internet which sounds very interesting and its goal is to simplify networking and enable new applications. I did not know that SDN is centralized control where switches are slaves. Applications have the control. Any routing algorithm can be used in SDN and IP becomes one forwarding protocol among others. The different SDN-layers were really interesting. It was great to see how much different it was and how it solves the problems that we are having with our current technology. Usage of SDN in 5G was also really interesting and how the requirements of 5G can be achieved with SDN. B. Problems and open issues The SDN control styles: proactive and reactive were little bit hard to understand. I understood that proactive is replacement for network management and reactive replaces network control but it was hard to understand what these “do” in real life. C. Relevance I think that the SDN-technology and its potential will be in a major part of my future studies because we need a new network architecture. The explosion of mobile devices and content among the trends driving the networking industry to re-examine traditional network architectures and SDN seems to be a great candidate. It would be interesting to hear more about the problems which SDN have related to 5G since there are some security issues. 3