Operating System Theory Final Project - CPT304 

       Summary Blog Post

         One of the key features of a contemporary operating system (OS) is the software needed to allow application programs like word and excel to run concurrently on the computer architecture. Since the CPU can only run one process at a time, the OS is used to manage when a process can access the CPU. The software used by the OS includes the code to manage; the memory, the file system, access to the CPU, and control for the I/O devices connected to the computer. The operating system memory management is needed to coordinate which applications programs will be stored in RAM and which will be stored on hard disk. The OS file system management organizes and keeps track of all programs and file on the hard disk, making it easier to access and retrieve files needed to run applications. The OS also determines when the CPU can be access by programs, devices, and other computers. Also, the OS is used to control I/O devices connected to the computer. See Figure 1.

Figure 1 - Operating System Theory Concept Map

        Operating systems enable processes to share information by allowing the contents of RAM memory, virtual memory, registers, the stack, schedulers, and multiplexors to be accessed by each process. An example of this is the storage and retrieval of information from executing a multithread user task. Also, the operating system allocates resources, provides protection, and security for the processes. “Operating system implements two basic functions below [1,2]: it must be simply use as extension machine and it must manage and distribute all kinds of resources reasonably as the manager of the computer system. In addition, some operating system also takes charge of the computer system’s safety and provides application-specific services, such as networking, graphic interface and so on [3,4].” (Jiang et. Al, (2010), page 2). See Figure 2 for example of OS processes and threads.

 

Figure 2 - Hierarchy of Operating System Subsystems

         Because the physical address space in a computer is limited to the size of the registers, caches, and RAM., resources such as code, data and files are shared. The total amount of memory stored on these devices is often not large enough to load and run all jobs to be executed. To solve this issue, memory-management can use virtual memory algorithms that uses the basic hardware to hold address and data information of files in the secondary storage unit that need to be bind to logical memory addresses and moved to an actual memory address when executed. These files are stored in a file system to be accessed by the OS when needed. See Figure 3.

Figure 3 – Memory Management

        The objective of file systems management, mass storage, and I/O code in the OS is to organize information in files on the secondary storage media, and to send and receive information from devices connected to the computer so it is easy to retrieve. The goal is to configure files in a format that will be efficient, fast, and easy locate, and allow a user to read, write, modify, or delete them from the hard disk. Also, the file systems management will allow the user to set parameters of a file that includes a file name, identifier, file type, size, logical address (location) on the hard disk. In addition, the time, date, user identification, are defined in a table when the directory list command is used. There are four basic types of directory structures, they are the single-level directory, the two-level directory, the tree-structure directory, and the acyclic-graph directory. Because of issues with overwriting file for the single-level directory, limited expansion for the two-level directory, and redundant files in the tree-structure directory, I would use the acyclic-graph directory structure. The Acyclic-graph directory allows sharing of directories and subdirectories. "With a shared file, only one actual file exists, so any changes made by one person are immediately visible to the other. Sharing is particularly important for subdirectories; a new file created by one person will automatically appear in all the shared subdirectories." (Silberschatz, A., Et al, p. 497). See Figure 4.

  

Figure 4 – Acyclic-graph File System

        One of the key mechanisms used by the OS to control access to devices is the controller. Controllers are a scaled down computer with only the necessary features and capabilities to do the functions it was design for such as, read the input from the keyboard or output data to the screen. Controllers can be found inside memory devices like RAM, Hard disks, the tape drive that runs the backup tapes, and in USB drives. In addition, controllers are used to control the flow of data on busses like the data bus and direct memory access (DMA) bus, the control the display devices like LCD monitors, and they control the input and output of data to the computer with network interface cards, serial ports, SCSI ports and more. See Figure 5.    

Figure 5 – Files, Mass Storage, and I/O Management using Controllers

 

        For future courses or jobs that involve software projects that need to interface with an OS, I would use the knowledge learn about processes and threads to maximize the capabilities of a uniprocessor or multiprocessor by including code that will allow processes or tasks to share resources and defined in the system architecture. Another thing I would include are the device libraries to provide code for controllers connected to the input and output devices needed. In cases where multi-users are required, an acyclic-graph file system would be used to allow common files to be shared and I would include protection and security measures such as passwords, encryption, and restrict user access as needed using permissions setup by the system administrator. 

Reference

Jiang, H., Gao, W., Wang, M., See, S., Yang, Y., Liu, W., and Wang, J. (2010), Research of an architecture of operating system kernel based on modularity concept, Mathematical and Computer Modelling, Volume 51, Issues 11–12, Pages 1421-1427, ISSN 0895-7177, https://doi.org/10.1016/j.mcm.2009.10.006. (https://www.sciencedirect.com/science/article/pii/S0895717709003

Silberschatz, A., Galvin, P. B., & Gagne, G. (2014). Operating system concepts essentials (2nd ed.). Retrieved from https://redshelf.com/.

 

Post #7 – Tech Topic Connection [CLOs: 1, 2, 3, 4, 5, 6]

       The Tech Topic I selected was software engineering. This topic interest me because, I want to know everything about how a computer related device or system works. I started working with computers and the ancillary equipment used with them more than 40 years ago (see Figure 1) and I had no problem analyzing the hardware. For the most parts, the software inside was like a black box. You know what goes in and what come out, but you are not sure how it works or how to make changes to improve the performance of a device or system. Those bits and bytes that make up the code that run the hardware remained a mystery to me for all those years. I have done some coding at both the high and low levels, but the programming languages are changing. In the beginning there was Basic, PASCAL, Fortran, and “C,” or “C++,” or you use could use machine languages. The next step I need to take to understanding how information systems work is to enhance my skills by my learning the latest programming languages and getting a degree in Software Engineering.

Figure 1 – Ancillary Equipment for Computers

In my career, I was primarily a tester and a designer of the hardware, there was not enough time to be trained or updated on the latest trends in programing languages or commands used for operating systems. I was limited as to what I do to make computer related devices or systems perform better. High level languages like Visual Basic, SQL, JAVA, Linux, and Python are now used to program all types of electronic devices from outdoor lighting fixtures to our smart phones. These programming languages are the keys that opens the door that allows new ideas in programming to becoming a reality. One of my goals is to be proficient in creating or modifying the software used in these devices and systems.

More than ever, we are allowing computer access and control to devices we need to use every day. Things like our cars can be programmed with a wireless remote can that automatically lock and unlock your car doors as you leave your car or return to it. Smart software can correct and finish your sentence faster than you can think or type it. We use software application in database management to create, manage and analyze all types of statical data such as, population growth, the changes in weather temperatures, the production rate of manufactured items, and the list goes on. It is amazing what can be done when you know how to program smart devices or computers, you can save money on powering down these devices not in use or you connect with websites to buy items online when the specials are available. You can program test equipment to monitor and if necessary, shutdown crucial equipment if a fault occurs.

Using software engineering many of the world problems can be solved if we apply its principles correctly. First, we must understand that a software engineer has a highly regarded position with great powers and like a superhero in the movies, with great powers come great responsibility. Software engineers can have fate of hundreds, thousands, or millions of people and the equipment needed to maintain the quality of life in their hands. They program equipment that control things like our power grid, our banking system, and even the distribution of medicines that can save lives. Without software engineering, the architecture, management, and security of IT networks could not be maintained because there would be no documentation providing operating procedures, no troubleshooting guides, or repair manuals. With software engineering expertise, IT systems can be made work flawlessly or in the cause of a hacker or software engineer turned rouge, these techniques can be used to create great havoc on society.

“Students who want to focus on software engineering are expected to gain and integrate knowledge from various subject areas including computer programming, data structures, algorithms, numerical methods, statistics, design patterns, human-computer interaction, computer graphics, information visualization, database systems, web development, software project management, and software engineering.” .  What Is Software Engineering | Computer Science & Engineering | University of Nevada, Reno (unr.edu).

There are many disciplines in the Information Technology (IT) field but, none come chose to software engineering. It is the methodology that determines how and when IT applications will be used, it sets the tone for what the limits are and what the returns should be. It includes the actual coding for programs that perform special tasks (calculations), control devices or analyzes data. In addition, software engineering provides the documentation to support IT products (these documents include specifications, instructions, test reports, and any other information to help users understand the deliverable product). Software engineering is the most popular and most challenging career path for information systems development. It encompasses every area of IT and provides the rules, baselines, and procedures to solve all professional level IT software problems. It is like the gasoline that makes a car go. You can make the best car in the world but, without the fuel, it is useless. In this analogy, software engineering the is the fuel that makes the IT industry go.

 

 

 

References

University of Nevada, Reno, Computer Science and Engineering Department (2022). What is Software Engineering.  What Is Software Engineering | Computer Science & Engineering | University of Nevada, Reno (unr.edu)

Oshana, R. and Kraeling, M. (2019 2^nd Edition). Software Engineering- for-Embedded Systems. Software Engineering for Embedded Systems | ScienceDirect

 Post #6 – Network Security [CLO: 6]

The importance of information and system security for the individual and organization can be seen in how we access the internet at home and work. Over the last twenty years the home life and the workplace were kept separate. Today the two lifestyles have merged into one. Things like dating and after work activities are connected to work over the internet by applications like Facebook (now called Meta) and LinkedIn. The information on these websites can be especially important and are often used to determine, job offers/promotions, match ups for dating, or a decision on marriage or breaking up. They help pick our coworkers, friends, provide advice on our finances, and health. These websites allow both personal and business information to be on the same platform and the security of that information vital. If that information falls into the hands of scammers, they can revel havoc for both businesses and individuals.

The websites discussed above can come under attack from many sources. One of these attacks is called the “Ping of Death,” it is done by sending multiple ping commands for a status check, where each message can be modified from 32 to 65,500 bytes (note: large messages are broken down into 32-byte packets when sent). The number of the messages will cause the website to receiving thousands of status requests at the same time and that will at some point cause it to slow down processing, overload, or crash. The flooding of data is called denial of service (DoS). See Figure 1. When this occurs the computer or website cannot provide normal services to its users. This is an internet vulnerability that can be fixed at the router by having it monitor the connection links between the sender and the website, and not allow a massive overflow of data to be sent to the website. Another method to block DoS attacks is a Firewall, which monitors the flow of data coming into the computer and will limit the network access if a certain threshold is exceeded. The following link provides supporting data for defending a computer against DoS attacks (Perform Ping of Death Attack Using CMD And Notepad (Just For Learning) (fossbytes.com)).

Figure 1. Ping of Death Attack

One of the most popular methods used by cybercriminals is social engineering. This approach uses manipulation techniques to convince people to willing give up important and confidential information on themselves or on businesses they work at. No actual hacking of the computer is needed when the targeted individual will provide access. This form of attack is called spear phishing, which uses information like names, email address, and location found on public websites to target specific individuals or organizations to get more detailed information like social security number, bank account number, or passwords to other accounts. Supporting evidence for the impact of social engineering on the internet can be found in the book:  Social Engineering – The Art of Psychological Warfare, Human Hacking, Persuasion, & Deception by Vince Reynolds, see reference below. In addition to social engineering, hackers may send you a phishing email which may contain malicious software that will install itself on your computer to collect information.

Today, we spend so much time responding to emails and text messages it has become hard to distinguish fraud from legitimate emails messages. Text and email messaging are usually very secure over a company network, but not as secure over a public network. Big companies spend millions of dollars on cybersecurity but, they are still as vulnerable as the individual who has limited funds to purchase the latest antivirus software. Therefore, phishing is still a major threat on the internet, there is no way to filter out the good from the fraudulent emails. The hackers and scammers have found ways to get around old antivirus software and send fraudulent emails and setup phony websites to obtain both personal and business information from people. These frauds have so convincing that is hard to tell them from legitimate websites. For example, the email in Figure 2 appears to be from Chase bank requesting information on an account. It asks the recipient to click on a link to proceed. If you look closer, you will see the email is not from Chase. The best way to protect your computer from social engineering or spam email attacks is to avoid opening an email that looks suspicious. If you do then, you should never click on a link you do not know and provide personal data. It is best to go directly to the website and log in to check on the status.

Figure 2. Phishing email example

Fake emails like the one above is not limited to Chase Bank, there are emails that appear to be from PayPal, Amazon, and other major companies. They all have a few things in common, one they warn of a loss of service or access, or they claim they are checking up on fraud, or some other problem and want you to provided account information, and the second thing they want you to click on or go to a website. this is a trap design to get you to reveal personal data of have you open a link that can load a virus on your computer, only good cyber security training can help you detect traps like this one and it is important to stay current on what threat are lurking around on the internet. Checking websites like Microsoft.com norton.com, and Google.com can provide the latest updates on what to look out for. Both Microsoft and Norton have software that will check your computer for viruses and provide a report on the status that will include how many security threats were detected and fixed. These Apps are important in maintaining high performance on your computer and can be used to keep your computer or website safe from hackers.

References

Chloe Pilette. (July 26, 2021). Norton LifeLock. What is social engineering? A definition + techniques to watch for (norton.com).

Vince Reynolds. (2015). Social Engineering – The Art of Psychological Warfare, Human Hacking, Persuasion, & Deception.

Hans Weber (2020). Hacking AI: Big and Complete Guide to Hacking, Security, AI, and Big Data. Page 74, 106 referenced.

Amar Shekhar. (January 10, 2022). Fossbytes. Perform Ping of Death Attack Using CMD And Notepad (Just For Learning) (fossbytes.com).

 Post #5 – Computers in the Workplace [CLOs: 1, 2]

        There are three components that make up an electric power system, generation, transmission, and distribution. Computers have a major role in developing, maintaining, and testing each component of the electric power system see Figure 1. They control, monitor, and analyze the flow of power from generation to the customer. 

Figure 1 – The Bulk Power System

        Another need for computers is to create Word documents and spreadsheets for the specifications and design standards of the power system (Figure 2 shows a design standard format in Word). 

Figure 2 - Typical Engineering Standard Document

        The SCADA (Supervisory Control and Data Acquisition) system used computers to monitor and control switchgear that is used to connect and disconnect power to the electric grid. Figure 2 show switchgear used to connect and disconnect distribution power under 10,000 volts.  

Figure 3 – Pad mount Switchgear

        The test equipment that checks the status of the electric circuits and equipment used in the power system use computers to run test routines to verify requirements are met. 

Figure 4 – A Hybrid Computer Used to Test Transformers

        Computers are used to perform load analysis on transformers to determine if it can handle the loads needed during peak hours of operation. Figures 5 show a transformer being tested and Figure 6 shows the computer used to monitor and record the test results. 

Figure 5 – Distribution Transformer Under Test

 

Figure 6 – Test Equipment Used to Monitor and Record Test Results

        Hybrid computers are also used in relays which are called IEDs (Intelligent electronic devices). These relays protect the power system from faults like lightning, short circuits, and overloads. They have communications ports for send status and receiving commands to open or close a circuit.

        Computers are used to design, generators, transmission line, distribution systems, all the devices needed to keep the power system up and running. Using CAD (computer aided design) software, drawings are developed specifying the characteristics of the components documented in the specification.

        Computers are used host the bidding software that publishes and receive bid requests for equipment and services needed to maintain the power system.

Figure 7 – Bidding Website Used to Procure Power System Equipment and Services

        Computers are also used in the meters that monitor and record the electricity used by customers. Most of these devices have wireless communications (Figure 8) and can be monitored from the main office computer or by handheld computers used in the field. 

 

Figure 8 – Power Meter with Wireless Communications (also called a hybrid computer)

        In summary, all power systems need a computer to operate efficiently. It provides personal with technical information on how to operate, repair, or analyze the components. Computers allow the remote operation of switchgear that can provide more power to customers when needed and reduce power when not needed. They also give customers real-time access to their bill to see if too much power is being used and allow them to make changes to reduce costs. The Power System uses all three types of computers, Analog computers for high-speed switch of relays, digital computers for the precision needed to calculate consumptions, and hybrid computer for testing circuits and equipment. Within the next ten years computers will be connected over wireless network and provide monitoring capabilities to identify faults like wildfires (hybrid computers with cameras and wireless communications are being tested to monitor powerlines in remote locations). Today there a cybersecurity concern with using wireless technology to control equipment, a hacker could connect to the grid from anywhere putting the Power System at risk. In the future, better security measures should be in place to prevent hacking wireless networks.

In response to comments from the discussion form I wanted to answer the question on why employees need to be computer literate, I can only vouch for the procedures used in the LADWP (Los Angeles Department of Water and Power).  At LADWP, all engineers, operators and electrical workers go through extensively training and certifications (when required) before being allowed to operate, maintain, install, or repair the equipment used in the power system. More than half of this training is with interactive programs on a computer (the rest of the training is on the actual equipment). In conclusion, all employees must use a computer to be certified before they are allowed to do any work on the power system. As to why employees need be able to use a computer in their work is simple, computers are used to document specifications, drawings, schematics, monitor and the status of equipment. Every aspect of the power system is either stored, displayed, controlled, or processed by computers and some level of knowledge of computers in needed by every employee in order to maintain and protect it.

There was also a suggestion that the power industry find ways to reduce power losses that occur during transmission and distribution. It is accepted that about 50 percent of the power generated will be lost before it reaches customers. This loss is due to the long distances the power must travel and the switching required to step-up of step-down the voltage. For each transformer used there are losses. Sometime the transmission line runs over a thousand miles and no matter what medium is used to carry the electricity. Trying to install zero lost conductors and improving transformer efficiency (the best transformers are at about 85 percent) is not particle with the technology we have today. Using better conductors is too expensive and it would not save enough power to justify. To compensate for the line losses, the electricity is step-up to high voltages like 100,000 or 700,000 volts, so line losses and transformer efficiency will not become a factor in distributing the power.

  

Post #4 – Traveling Through a Network [CLO: 6]

        The Ping command verifies the connectivity of your computer to another device over internet or ethernet. Ping will access the other device very much like you make a phone call on a land line. You need to know the recipient’s number (in this case it is the internet protocol (IP) address or domain name) to complete the connection. When you ping a valid IP address or domain name, the computer will display your destination’s 32-byte IP address or domain name, the size of the packet, the time it took to make a round-trip connection, and the TTL (time to live) limit which is the number of rebroadcasts each host can make. 

        Traceroute tracks the number of networks (hops) a message must pass through to go from the host computer to its’ destination. Traceroute will display each network name, IP address, and the time it takes for a message to go from a host to the recipient. By looking at the traceroute results, you can see if there are delays, a connection failure, and sometimes it will tell you if there are problems with the network.

Ping

        The first part of the interactive assignment was to ping “Google.com” and two other websites outside the country.  

        Pinging Google.com sent an “echo” request to IP address 142.251.33.78. To make sure there is a good connection four packets were sent and returned with 0% loss. Each message was 32-bytes of data, the average time to complete the round trip was 40ms, and the TTL was 92.

         The second ping I sent was to gov.uk, IP address 151.101.192.144. This is the official site for the United Kingdom website. Four packets were and returned with 0% loss. Each message was 32-bytes of data, the average time to complete the round trip was 42ms, and the TTL was 34.

 

        The third ping I sent was to amazon.jp, IP address 99.86.128.253. This Amazon’s website for Japan. Four packets were and returned with 0% loss. Each message was 32-bytes of data, the average time to complete the round trip was 32ms, and the TTL was 230.

Traceroute

        The second part of the interactive assignment was to do a traceroute on “Google.com” and two other websites outside the country.

        The first requirement was to send a traceroute to Google.com. With traceroute, three packets are sent versus four for ping, the results for the round-trip-times (RTTs) are displayed in columns 2, 3, and 4. Column one displays the hops number and column five lists the domain name or IP address. When the “traceroute” command was executed for Google.com, the results showed that it took twenty-eight hops to complete the task, four requests timed out, and on the 23rd hop, only the second RTT was successfully. The average time for each hop was about 42ms.

 

        When the traceroute was executed for gov.uk, the results showed that it took 30 hops to complete the task, six requests timed out, and on the 28th attempt the third hop failed. The average time for each hop was about 44ms. 

        When the traceroute was performed on amazon.jp, the results showed that it took 30 hops to complete the task, four requests timed out. The average time for each hop was about 44ms. Note how the time ranges from a low of 31ms to a high of 73ms and packets. This is mainly because of the longer times are needed for overseas connections.

Reflection Essay on Using Ping and Tracer

        In summary, using the “ping” and “traceroute” commands in the is exercise has helped to learn how devices connect over the internet. I have connected computers and networks in the pass using an RG-45 cable for the connection. Some RG-45 cables have LED lights that show if the connect was good or bad. This made checking the status easy. Using the ping and tracer commands, I now understand more about what’s happening then just looking at LED lights. These commands show what types of packets are being sent, where the packet goes, how long it takes, and how to troubleshoot connection problems.

         Ping checks the status of a connection between the source and destination. It displays the number of packets sent and received back, the time it takes to make the round trip, and returns a blank cursor if no connection was made or the destination has put up a” firewall”. 

        I was able to send pings successfully to three different websites with 0% lost. If a packet is lost, then most likely there was congestion on the network or a hardware failure. The “traceroute” request returned information about the hops needed send three packets from the source to the destination. My computer displayed a list of networks that the traceroute packets passed through, the total number of hops heeded to connect to the destination (the maximum hops was set to not exceed 30), the RTT, and the domain name or IP address for each hop. In performing a traceroute to websites like Google.com, gov.uk, and amazon.jp, I noted that 30 hops are not always needed to make a connection. However, I did get several request timeouts, so multiple attempts are needed to ensure a good connection. It seems that the further from the source, the more timeouts occurred. From the comments I receive in the discussion, most of my classmate experienced the same things I did, such as timing delays in messages going to the same location may vary a little because of other senders trying to connect to the server. And the number of hops will also depend on the fastest available path to get the message thru. If some servers are down, busy, or put up a Firewall, then the request message will search for the next link that is free to receive the message. Sending packets overseas it took more time to complete the RTT and I had more request time outs. If a request is timed out it usually means that the device is turned offline, or a firewall has been put up to block unauthorized access. Analyzing the displayed results, you can see how many hops were made, how long it takes to connect to a website, and if there are issues making the connection. For example, connecting to Google.com it took 28 hops with 5 RTOs, gov.uk it took 30 hops with 6 RTOs, and amazon.jp took 18 hops with 5 RTOs. Connecting to longer distances doe does not mean you will have to use more hops. Connecting to amazon.jp in Japan took less hops than with Google.com, which is thousands of miles closer. With these new tools I can be more effective in troubleshooting network problems on my computer.

References:

TTL (Time To Live) Definition (techterms.com)

https://www.sciencedirect.com/

 

Post #3 – Documenting a Day [CLOs: 4, 5]

        In this journal entry I will be writing about the tasks I perform during a 24-hour period. The day I picked was Thursday, January 27, 2022. During this day, I performed the tasks listed below:

Task List for January 27, 2022

1.                  Worked on Week 2 Assignments 1 & 2

2.                  Completed and submitted Discussion for Week 2.

3.                  Got ready for Work.

4.                  Went shopping.

5.                  Checked emails, text, and voice messages.

6.                  Drove to and from work.

7.                  Performed regular work tasks

8.                  Performed special work tasks

9.                  Family time

10.              Sleep time

 

        The day begins with me going to sleep at midnight. I have an evening job and sometimes I do not get to bed until late. I slept to about 5 AM, when my wife wrote me up to discuss things to do for the day (my wife leaves for work shortly after 5 AM, and when I get home at night, she is asleep). I acknowledged her requests and went back to sleep until 7AM when I wrote up again and got my coffee. After a few minutes I am alert enough to get on the computer to look at my emails. I responded to a couple of messages that require attention. One message was from Amazon.com. Apparently, the computer I was using to work on the Week 2 Discussion wasn’t registered with my account and I had to respond by email to approve the use of the device. Next, I checked my phone for missed calls, voicemail, and text messages. Everything looked good and I was ready to continue with my other morning tasks.

 

        The next task I worked on was my Week 2 Discussion. It was nearly completed, and I just had to review the contents and verify that all the assignment requirements were met. After checking the discussion, I made a few changes and submitted it. Next, I continued to work on the other assignments for Week 2. I completed the outline for the Word document and formatted the Excel spreadsheet. After completing these tasks, it was 10 AM and I needed to get ready to go to work. Some people take work preparation lightly and only allocate a few minutes to do it. I set aside about one-hour to get ready. During this time, I normally, shave, shower, dress, have breakfast, and prepare my lunch. All these things are important to me, and they make sure I am well prepared when I leave for work. On this day, as I started getting ready, I got a text message from my supervisor requesting I come in early. I skipped breakfast and left early, not knowing why I needed to come in early.

 

        My job is about twenty-five miles from my house, and I take the freeway to get there. It can be a challenge because of the construction projects that can delay traffic. I usually allow about one-hour to get to work. The traffic was moving fast, and I got to work in 35 minutes.

        Once at work, I found out that our location was getting a surprise visit form the regional manager and I needed to make sure the mail processing equipment was setup and the advertising mail for the mail carriers was distributed. In addition, our dispatcher was not there, and I had to setup the post office dock for sending and receiving the mail. Working fast, I was able to get everything ready just in time. When the regional manager arrived, everything looked good, and she skipped the inspection. After that exercise, I was able to continue my regular duties which are to; log and record the incoming mail parcels and distribute them to the mail carrier stations. Normally, I process between 1000 and 1500 parcel a day and I was well on my way to doing this when I got called to go help a stranded mail carrier who had locked himself out of his vehicle. It was after 5 PM and it was getting dark. With poor lighting in the dark, I had to drive more than ten miles in evening traffic to a place I never been before to get to him. To make matters worse he was at a mail station hidden on a one-way street in a dark corner of a small shopping center. I tried to use Google Maps, but it did not make sense and I drove by his location serval times. I had to call my supervisor, who described some key details about the location that helped me. After I founded the mail carrier, I gave him a set of keys, one of the keys fit and he was able to get into his vehicle. The timing was perfect, because the carrier had to take some medication and was about to break the window to get in his vehicle. I return to my work location, and I processed over 1400 parcels for the day.

 

        I left work at 10:30 PM. However, I still had to do some shopping. Thankfully, there was an Albertson Supermarket less than a block from my job and I was able to get there and pick-up the things my wife had requested. Coming home, the traffic was not good. I experienced a freeway closure, and it more than an hour. When I got home at 11:45 PM, I spent about 15 minutes checking emails before I went to bed at midnight again.

Excel Spreadsheet

Power Point Presentation

 Post #2 – Web/Mobile App Critique [CLO: 4]

Hello class! I chose the Amazon Prime app because it has an app for shopping and includes free apps like Amazon Music and Amazon Fire. I used these apps for several years for online shopping, streaming services, and product research. In this discussion I will cover some of the capabilities and features of the app, how I have used it to help find the best products, streamed videos, and music for about anything of which you can think.

The designers did an excellent job making it compatible with smart phones, smart TVs, and other devices with internet or Wi-Fi connections. I can use this app anywhere there is access to the internet. The Amazon Prime home page (Figure 1) layouts the key topics and provides a search option for any subject not listed. For example, the home page provides a list of the most popular products and services provided, if you find something that interests you, just move the mouse curser on that icon and click, the app will automatically send you to a web page for that item or service (Figure 2). Once on the new page, you get a list of products. Each item is rated on customer reviews, the price, shipping costs (many of the Prime items have free shipping), and delivery date are displayed. By clicking on a product more details, specifications, and features are shown. Going back to the search result page, you will find on the left-hand side a column where you can refine your search by, price, name brand, product rating, or for some products you can select detail specifications, like size, weight, or color (Figure 3). The home page includes a list of your previous purchases, product searches, and related items. This this useful because it allows you to keep record of your session for future reference.

The best way to demonstrate the usability and functionality of the Amazon Prime app is to do a search for an item. I will do a search for a curved monitor to use with my laptop. I will make the requirements simple, cost less than $400, it must have a high-resolution display, LED, aspect ratio of 16:9, and at least 30 inches. Using Amazon to search for a curved monitor is easy, you just type in the product name and click on the search icon.

Figure 1 Amazon Prime Home Page

 

Figure 2 Search results for a curved monitor

Figure 3 The usability of Amazon Prime to refine the search parameters.

In the search results you will find a list of products to choose from. if you scroll down on the page, you will see the comparison table (Figure 4) that lists the best options. This table will show the most notable features and capabilities, customer ratings, delivery options, and cost. To select, just click on “Add to Cart” and you will go to the check-out page. The check-out page shows all your purchases and allows you to make changes or add/delete items before finalizing your purchase. The service provided by Amazon is good and I can usually find items or products on their site that are not available anywhere else. The site does list new and used items and this how they differ from other shopping sites. Adding used items as an option increases the availability and reduces the cost of products.

Figure 4 Comparison of different curved monitors

One of the issues with the Amazon Prime app are the customer reviews. Since it is all done by Amazon, there is no way to know for sure how accurate it is. They only highlight the 4 and 5 five-star reviews. The best way to resolve this is to have a non-profit or government agency review the customer satisfaction rating. Another issue is how hard it is for small businesses to put their products on Amazon to sell. The setup is complicated (there are at least ten forms and agreements you need to process), the costs are too high, they charge a fee and a sizable percentage of the profits. This can make it too expensive for small businesses to use their service. Amazon needs to reduce or simplify the number of forms and delete the fees for small business to put their product on the website.