CS Learning Journal

  WELCOME TO WEEK 5 Learning Journal This week, we are covering the first part of the network layer, focusing mainly on the data plane. Next week, we will focus on the control plane of the network layer. We already know that the role of this layer is to move packets from the sending host to the receiving host. However, the network layer is the most complex layer of the protocol stack. The two key functions of the network layer are forwarding and routing. The difference between routing and forwarding is as follows: Routing is the process by which the path a packet takes from the source to its destination is determined. This process involves all of a network’s routers, whose interactions via routing protocols determine these paths. Routing is a global process that involves multiple routers working together across the network to find the best path. Forwarding, on the other hand, is the process of transferring a packet from an incoming link to the appropriate outgoing link within a single

  WELCOME TO WEEK 4 Learning Journal This week was shorter than usual because we had the midterm. It really helped to have a lighter workload since it gave me more time to study and review for the test. The topic for this week was network security, which we briefly discussed in Chapter 1. However, in Chapter 8, we delved deeper into the principles of cryptography, focusing on how to provide confidentiality, integrity, authentication, and non-repudiation. We began by understanding the language of cryptography, where keys are used to encrypt plaintext and decrypt ciphertext. We also discussed the differences between symmetric key cryptography and public key cryptography. In symmetric key cryptography, both the sender and the receiver must know and use the same shared secret key. The challenge with this approach is that securely transmitting the key to the other party is difficult, especially if the parties have never met. Public key cryptography, on the other hand, works differently. The

  WELCOME TO WEEK 3 Learning Journal This week, I learned a lot of new concepts. However, it felt more time-consuming due to the team project on top of our weekly assignments. Fortunately, I took a couple of days off to catch up with everything. Despite the workload, it was an interesting week. We moved on to the transport layer and explored how one host sends data to another over a network. We began with the concepts of multiplexing and demultiplexing. Multiplexing involves gathering data from the application layer, encapsulating it into transport layer segments, and passing it to the network layer (IP). When the data reaches the other host, the demultiplexing process takes those received segments from the network layer, decapsulates them, and sends them up to the appropriate application layer process. Demultiplexing at the receiver is guided by headers, which include the destination port number to identify the destination application program. As we focused on the transport layer, it

  WELCOME TO WEEK 2 Learning Journal      This week, I learned about the principles of network applications. One of the key concepts I learned is that these applications can have two possible structures: client-server or peer-to-peer (P2P). In the client-server architecture, the server has a permanent IP address and is an always-on host. However, a single server is incapable of handling all client requests, which is why data centers (which house many servers) are created. Clients communicate with the server but are only connected when needed. They may have dynamic IP addresses and don't communicate directly with other clients. In the P2P architecture, there is no always-on server. Instead, end systems communicate directly with each other. Peers can act as clients (requesting services) or servers (providing services). In P2P, peers are intermittently connected, and their IP addresses can change frequently.     I also learned more about the internet's transport protocol service

  WELCOME TO WEEK 1 Learning Journal This week has been really good so far. I learned a lot of new things that I found very interesting. To begin with, this week's chapter started with an introduction to what the internet is and how it is viewed. It is first described as the "nuts and bolts," where it talks about all the hardware and software that is involved. For example, there are billions of computing devices such as hosts (or end systems) running network applications. Hosts can be a PC, server, laptop, smartphone, etc. In order to carry signals across from one end system to another, there are communication links such as wired or wireless links. There are also intermediate devices called packet switches, which forward packets. There are also protocols that control the sending and receiving of messages sent from one end system to another. Some examples of these protocols are TCP and IP. Protocols are used to define the format and order of the messages that are being sen