About Me >>   Bachelor's Degree >>   IT-201 Computer Platform Technologies

SNHU - IT-201 Computer Platform Technologies
Written by: Chris Bell - September, 2012

Communication Protocols and Network Building

1. What is the purpose of communication protocols?

The purpose of a communication protocol is to assure the correct receipt of data that was sent. The designated protocol sifts through the data to find and correct errors and also to authenticate the message being sent. It's similar to the quality control department of an organization.

2. What are examples of communication media? What are their characteristics (e.g., bandwidth, relative price, etc.)?

Some types of communication media include newspapers, websites, social media, phone apps and magazines. The characteristics change drastically between each type however anyone trying to get their information out to the world should participate in each regardless of the cost. Just like anything else, things evolve as newspapers and magazines became websites and websites became social media and apps. The bandwidth is the greatest with social media because it sends the data directly to the reader and it also allows for the reader to distribute it to all of their social media contacts.

3. What is the importance of error detection? Of error correction?

Error detection is very important and the correction of the errors is even more important. The Internet has grown very quickly due to the ease of use, quickness of data viewing and immediate availability. More people would still be using newspapers and magazines if they constantly got error codes or incorrect data when trying to view information online. Any process or protocol is going to be subjected to continuous improvement and error detection and correction is a top bullet point.

4. What are the advantages and disadvantages of each of the four main physical network topologies?

Mesh, bus, ring and star are all types of physical topologies that connect computers to local area networks (LAN) and LAN's to wide area networks similar to how driveways connect to neighborhood roads and those connect to main roads and highways. Advantages of topologies are that they connect nodes to other nodes, transmission lines and shared hubs. Cost is the main disadvantage due to newer technologies that are faster and cheaper.

5. What is the purpose of network interface cards (NICs), switches, routers, and wireless access points?

The purpose of NICs is to connect computers to the local area network. The same interface card must be installed into the motherboard of each computer and the switches, routers and wireless access points allow each of the computers on the network to communicate together.

6. What is the purpose of the Open Systems Interconnection (OSI) model? What are the seven layers?

The seven layers of the OSI model starting with the first are physical, data link, network, transport, session, presentation and application. It is a protocol of steps that must be taken during data communication that detects and corrects any errors that could've occurred during the transfer.

7. Discuss the two main synchronizations problems that can occur during message transmission.

The two main problems that occur during message transmission are keeping the sender and receiver clocks synchronized and synchronizing the start of each message. Synchronization wouldn't be a problem if the network used the same clock but most computers have an individual system clock. Therefore quality checks of each message must be performed in order to be sure data is transmitting without errors.

8. List and describe two physical network topologies.

Bus is a physical topology that is common in most wireless networks. It connects every node to a single shared transmission line. The start connects every node to a node, switch or router. The star has very simple wiring which now uses two transmission lines between each node and the central nodes.

9. Describe the Open Systems Interconnection (OSI) model and explain its importance in interconnecting network devices.

The OSI model is to a network what a quality control department is to a company. Each data transmission goes through the "quality department" to check for errors, fix them and send them to the receiver. When added data to a shared network one wants to be sure that it shows up exactly the same on all of the computers of the network so it needs to go through a protocol in order to be sure it's accurate.

10. Describe two characteristics that show the difference between error detection and error correction methods.

Error detection methods include possibly sending 3 copies of the same data in order to show that they end up the same. The problem with that is the network can only be used at a third of its capacity. Other types include parity, block and cyclic redundancy checking. Parity checking basically checks for discrepancies throughout the bits which is a bit more difficult to implement but it can be more effective especially if you need to utilize more than a third of the network capacity.