Computer Science Homework Help

Need response to 2 student’s DB posts in 150 words each.

Student Answer 1:by Adithi Thumballi Ganapathi – Sunday, October 24, 2021, 5:10 PMNumber of replies: 1

A network model can be defined as a database that is made as a suitable approach to represent objects and their relationships with one another. Hence, the model is a schema in the form of a graph where edges/arcs define the relationship while nodes represent the actual network objects.

The network model was first made by Charles Bachman. In 1969, at the conference of system languages, the proposed system model was converted into proper stander specification. Actual practical implementations were done after the second publication in 1971 which was later more often used in the development of high-level relational models. The network model overcame the drawbacks of the lower flexibility of the hierarchical model. The main benefits that network model bought to the table were, a) It was a very simple concept with one parent having the ability to form various many to many relationships with other nodes (2011). b) Accessing data is very simple as compared to the other older models, c) In the network model, data integrity is always maintained.

The four layers of the TCP/IP model are Application Layer, Transport Layer, Internet Layer, and Network Layer. All 4 layers work in collaboration to transmit data from one layer to the other. The application layer is the closed layer to the application which helps the application to correctly access the network resources (2001). The transport layer is built on the top of the network layer in the OSI model which provides transportation of data of a process from the source to the correct destination on the machine or network level. Network layer is the second layer of the model which helps to send data packets from any network continuously till the packets reach the destination. The last layer is the Link layer which sets proper definitions about how the packets should be sent.

Network Protocols are said to be a well-defined set of rules and definitions to determine how data packets are transmitted between various devices present on the same network (2006). In other words, it can be said as how these devices communicate with each other without considering their internal processing. Some of the most used protocols are TCP, IP, HTTP, DNS, SNMP, SMTP, etc. HTTP is the most common among them. HTTP is also known as Hypertext Transfer Protocol is the basis of WWW (World Wide Web). HTTP is used for transferring data of webpages from HTTP servers to the client machines.

References –

1) TCP/IP and the OSI model. (2001). Designing A Wireless Network, 73–114. https://doi.org/10.1016/b978-192899445-9/50008-x

2) Basic concepts. (2006). Computer Network Time Synchronization, 19–32. https://doi.org/10.1201/9781420006155-5

3) Dynamic Network models. (2011). Network Models in Optimization and Their Applications in Practice, 105–146. https://doi.org/10.1002/9781118033173.ch4

Student Answer 2:by Jahnavi Nadipi – Wednesday, October 27, 2021, 6:47 AMNumber of replies: 1

In the early 1970s, the concept of open network models appeared, and a network model appeared which was more hierarchical in nature, rather than the more linear approach of the relational database. The two models are the hierarchical model, also called the network model, and the object-relational model, also called the relational model. This concept was later extended to be used to describe the object-relational model. A network is a directed graph, in which the nodes represent objects and the arcs represent relationships. To each node, a type is assigned, called the type of the node. When a node has no relationships, it is called a root node. Typically, there is one root node. There is no relationship between the nodes, so each node has a unique number. In the network model, there is no data table. Instead, the relational model is replaced by a network model, in which the data is stored at the nodes. This is often called object-oriented database (OODB) data, or network data, or a network database (Haigh et al.,2015). The relationships are the links in the network, and these are often stored in a data structure called a graph, that is associated with each node. In a network database, data is stored as nodes, and relationships are represented as links between nodes. These can be seen as being analogous to the tables of an RDBMS, but with more complex structure. This makes it more challenging to design and implement, and this is reflected in the design of the database. A number of features make the network model more effective than the RDBMS. For example, a node can contain any type of data that may be found in an RDBMS. You may have a node to store the image data from a picture of a product, another node to store the price of the product, another node to store the description of the product, and so on. As there is no fixed schema in the network model, you can easily switch out the nodes to store different types of data, without having to change the schema (Khaled et al.,2016).

References:

Haigh, T., Russell, A. L., & Dutton, W. H. (2015). Histories of the Internet: Introducing a special issue of information & culture. Information & Culture, 50(2), 143-159.

Khaled, O., Marín, A., Almenares, F., Arias, P., & Díaz, D. (2016). Analysis of secure TCP/IP profile in 61850 based substation automation system for smart grids. International Journal of Distributed Sensor Networks, 12(4), 5793183.