switches routers data encryption error detection remote file access email client B u s i n e s s F i n a n c e

Discussion – Due Feb/11

Prior to beginning work on this interactive assignment, read the The Differences Between Routers, Switches and Hubs (Links to an external site.) and the Topology- Definition and Types of Topology (Links to an external site.) and the Topology- Definition and Types of Topology (Links to an external site.) online articles, and review any relevant information in this week’s lecture. For this interactive assignment you will take on the role of an IT employee for a small family-owned business consisting of an owner, an office manager, a secretary, and four agents. Please review the scenario before drafting your post.

Scenario

The company has asked you to implement a network to improve how they conduct business within the organization. The company occupies a two-story building in an office park. Their volume of business had been stable for the past three years, but has recently begun to increase. To handle the increased business volume, two new agents will be hired, along with a team of web designers and developers to create a web presence. Everyone in the company has a computer, but the business manager has the only printer. These computers are not connected by any form of network. When agents need to print a document, they must first copy the file to a USB stick and then carry it to the business manager’s computer, where they are finally able to print it. Similarly, when staff members want to share data, the only means available is to copy the data to a USB stick and insert it into another computer.

Recently, problems have arisen with the current setup. The business manager is spending too much time printing other people’s documents, and it is frequently unclear which copy of a given document is the latest version.

After carefully reviewing the scenario, research a minimum of two additional credible sources that address the topics. (Access the MISM Credible Resource Guide for assistance with finding appropriate credible professional resources.)

Design a network for this company to support file, print, and web services. In a separate attachment, create a high-level network diagram that captures your solution. The diagram needs to show at minimum the cloud (Internet Service Provider), router, switch(es), printer(s), server(s), end-user computers, and how they all connect to one another.

Explain the key differences among hubs, switches, and routers.

Explain how and why the hubs, switches and routers you’ve included in your diagram will be utilized on your network.

Apply standard principles of design to recommend the network topology that would be most suitable for the business needs outlined, and defend your choice with a comparison explanation among the different topology types.

Evaluate the networking needs of the company and suggest either a peer-to-peer or server-based network, and provide the rational for your choice. 

Finally, suggest at least two ways to segment this small office network, and evaluate the associated benefits and limitations. Apply telecommunication and network technical knowledge to support your choices.  

Your initial post should be a minimum of 300 words, in addition to the network design attachment.

Assignment – Due Feb/16

Prior to beginning work on this assignment read chapter 7 in your text, review the Layers in the OSI Model of a Computer Network (Links to an external site.) online article, read the Kayri and Kayri (Links to an external site.) (2010) article, and review any relevant information in this week’s lecture. You will use these sources to support your work in the assignment.

The Open Systems Internconnection (OSI) model is a theoretical framework that separates the different aspects of networking into seven layers. Understanding these layers and evaluating how they are interconnected and the taxonomy used will provide greater knowledge and assist you to develop skills in the realm of networking.

• For this assignment, you will apply telecommunication and network technical knowledge to address the following elements.
• Describe the seven layers of the OSI Model.
• Compare the relationship between the OSI Model and the TCP/IP protocol using both a graphical and descriptive representation.
• Apply standard principles of design to the conceptualization of the OSI model and explain how a network engineer can use the OSI model to help troubleshoot a networking problem.
• Explain in which layer of the OSI model the following networking devices and functions can be found. Using your required sources, support your choice of the OSI model layers with a brief explanation of each of the following.
• Switches

Routers

Data encryption

Error detection

Remote file access

Email client

The assignment

Must be three to four double-spaced pages (900-1200 words) in length (not including title and references pages) and formatted according to APA

Weekly Lecture

Week Two Lecture

This week covers the Open System Interconnection (OSI) model. Many things in the networking world will become clearer for you once you understand the OSI model. This is because the OSI is so large that it touches on many interrelated topics. There are five layers in the OSI model that will be discussed in this lecture. In ordinal order they are: physical, data, network, transport, and application.

The first layer is the physical layer. This is where you find simple hubs, because all they do is connect devices for communication. The second layer in the OSI model is the data layer, which handles hardware addresses like the MAC address. Switches operate at this layer because they can process information based on MAC address. Figure 1 shows that computer X wants to send a packet to computer Y. The packet is sent to the local switch (Switch A), which then decides how to forward the information. This is based on the destination address which sends it to switch B. Then switch B needs to make a forwarding decision so it sends the packet to switch F, which is the local switch to computer Y; switch F then delivers the packet to computer Y.

• A data packet contains the sender’s message along with the address of the sending computer, as well as the address of the receiving computer. Just like the paper envelop we use to mail our letters, it has a destination address and a return address. As a result of this methodology, networks today are referred to as packet-switched networks.
• 
• Figure 1. Physical and data links. Reprinted from Data communications and computer networks, by C. M. White, 2015, Boston, MA: Cengage Learning
• One problem in connecting to different types of switches and networks is that they often use incompatible data link technologies. They organize packets in different ways, and have incompatible addressing systems. To handle these issues, the networking layer was created to address the incompatibilities of disparate networking technologies. Note that the networking layer is also interchangeable with the internet layer, which in this case is an abbreviated version of inter-networking and refers to communications between disparate network topologies. The networking (internet) layer is the third layer of the OSI model, and it is this layer that the universal identifier the Internet Protocol (IP) address calls home. The networking layer is concerned with universal addressing, packet formatting, and moving the packets across an internet.

The fourth level of the OSI model is the transport layer. The transport layer, which is above the networking layer, is only concerned with what happens on the source host and destination host. On the source host, the transport layer takes application messages and divides them into small units called segments. It passes each segment down to the internet layer, which places each segment into a single packet and sends the packet on its way. On the destination host, the internet layer program removes the segment and passes the segment up to the transport layer program. The transport layer program reassembles the segments into the original application message and passes the message to the appropriate application program.

• This slide shows the relationship between the networking layer and the transport layer.
• 
• Figure 2. Transport and Internet layers. Reprinted from Data communications and computer networks, by C. M. White, 2015, Boston, MA: Cengage Learning
• The transport layer has a number of other important functions. It typically provides error correction, which means that packets that are damaged or lost in transmission are re-transmitted. The transport layer also causes the source host to reduce its transmission rate if there is congestion. Overall, you can think of it like this: the internet layer is a best-effort service that tries to get packets through but may fail in the process. It may even deliver packets out of sequence. So what steps in to save the day? The transport layer usually is the fix-up layer that supplies the functionality that the internet layer lacks.
• The final layer of the OSI model this lecture will address is the application layer. This layer controls communication between the two application programs that are communicating. For example, when browsers talk to webservers, this requires application layer standards likes HTTP or HTTPS to specify the communication. There are many applications and many of them have their own standards. As a result of this large number of applications, there are more application layer standards than there are standards at other layers, for example, email uses standards like SMTP, which stands for simple mail transfer protocol. To transfer files we use the FTP standard which stands for file transfer protocol. So again, many applications, and many protocols.
• in summary, these are the five layers discussed in this lecture. Figure 3 shows how the five layers fit together. Each layer provides services to the layer above it. The bottom two layers provide transmission through single networks. The internet and transport layer provide host-to-host transmission through an internet to multiple networks consisting of diverse topologies. Finally, the application layer provides application to application communication and is the visual manifestation and results of the data communication process.