Computers and Networks (Unit 4)
Add Definitions from Unit 4 Computer Systems and Networks
Requirements
Work through College Board Unit 4… blog, add definitions, and pictures. Be creative, for instance make a story of Computing and Networks that is related to your PBL experiences this year.
How a Computer Works
As we have learned, a computer needs aa program to do something smart. The sequence of a program initiates a series of actions with the computers Central Processing Unit (CPU). This component is essentially a binary machine focussing on program instructions provided. The CPU retrieives and stores the data it acts upon in Random Access Memory (RAM). Between the CPU, RAM, and Storage Devices a computer can work with many programs and large amounts of data.
List specification of your Computer, or Computers if working as Pair/Trio
- Processor GHz: AMD Ryzen 7 5700U with Radeon Graphics 1.80 GHz
- Memory in GB: 12 GB
- Storage in GB: 474 GB
- OS: Windows 11 Home
Define or describe usage of Computer using Computer Programs. Pictures are preferred over a lot of text. Use your experience.
- Input devices: Interactive elements used by the user. EX: keyboard, mouse, touchpad
- Output devices: Elements of a computer that respond based on or to the user input. EX: headphones, speaker, monitor
- Program File: Files that are executed by computers in order to run a program. EX: web applications.
- Program Code: Instructions given to a machine to create a computer program. EX: web application code.
- Processes: Instance of a program running in a computer. EX: searching, debugging, etc
- Ports: Virtual point where network connections start and end.
- Data File: File that stores data to be used by an application or system. It contains actual data, or a view of the data. It also allows us to store information permanently and to access later on and alter that information whenever necessary.
- Inspect Running Code: Method of debugging a program code while it is running to check all functionalities.
- Inspect Variables: A subcategory of inspecting running code which allows the user to inspect variables in the program code in real time.
The Internet
Watch/review College Board Daily Video for 4.1.1
- Essential Knowledge
- A computing device is a physical artifact that can run a program. Some examples include computers, tablets, servers, routers, and smart sensors.
- A computing system is a group of computing devices and programs working together for a common purpose.
- A computer network is a group of interconnected computing devices capable of sending or receiving data.
- A computer network is a type of computing system.
- A path between two computing devices on a computer network (a sender and a receiver) is a sequence of directly connected computing devices that begins at the sender and ends at the receiver.
- Routing is the process of finding a path from sender to receiver.
- The bandwidth of a computer network is the maximum amount of data that can be sent in a fixed amount of time.
- Bandwidth is usually measured in bits per second
- Complete Vocabulary Matching Activity. Incorporate this into your learnings from year. To analyze measure path and latency use
traceroute
andping
commands from Linux Terminal.- Path: A
- Route: E
- Computer System: B
- Computer Device: C
- Bandwidth: D
- Computer Network: F
Watch/review College Board Daily Video 4.1.2
- Complete True of False Questions
T
F
F
T
F
F
T
- Essential Knowledge
- The internet is a computer network consisting of interconnected networks that use standardized, open (nonproprierary) communication protocols.
- Access to the internet depends on the ability to connect a computing device to an internet connected device.
- A protocol is an agreed-upon set of rules that specify the behavior of a system.
- The protocols used in the internet are open, which allows users to easily connect additional computing devices to the internet.
- Routing on the internet is usually dynamic; it is not specified in advance
- The scalability of a system is the capacity for the system to change in size and scale to meet new demands.
- The internet was designed to be scalable
- Information is passed through the internet as a data stream. Data streams contain chunks of data, which are encapsulated in packets.
- Packets contain a chunk of data and metadata used for routing the packet between the origin and the destination on the internet, as well as for data reassembly.
- Packets may arrive at the destination in order, out of order, or not at all
- IP, TCP and UDP are common protocols used on the internet.
- The world wide web is a system of linked pages, programs, and files.
- HTTP is a protocol used by the world wide web
- The world wide web uses the internet
- Go over AP videos, vocabulary, and essential knowledge. Draw a diagram showing the internet and its many levels. A preferred diagram would using your knowledge of frontend, backend, deployment, etc. Picture would highligh vocabulary by illustration. The below illustration have some ideas
- Often we draw pictures of machines communicating over the Internet with arrows. However, the real communication goes through protocol layers and the machine and then is trasported of the network. For College Board and future Computer Knowledge you should become familiar with the following …
User Machine <---> Frontend Server <---> Backend Server
+-----------+ +-----------+ +-----------+
| Browser | | GH Page | | Flask |
+-----------+ ^ +-----------+ ^ +-----------+
| HTTP | | | HTTP | | | HTTP |
+-----------+ | +-----------+ | +-----------+
| TCP | | | TCP | | | TCP |
+-----------+ | +-----------+ | +-----------+
| IP | V | IP | V | IP |
+-----------+ +-----------+ +-----------+
| Network | <---> | Network | <---> | Network |
+-----------+ +-----------+ +-----------+
The “http” layer is an application layer protocol in the TCP/IP stack, used for communication between web browsers and web servers. It is the protocol used for transmitting data over the World Wide Web.
The “transport” layer (TCP) is responsible for providing reliable data transfer between applications running on different hosts. The TCP protocol segments the data into smaller chunks called “segments”. Each segment contains a sequence number that identifies its position in the original stream of data, as well as other control information such as source and destination port numbers, and checksums for error detection.
The “ip” layer is responsible for packetizing data received from the TCP layer of the protocol stack, and then encapsulating the data into IP packets. The IP packets are then sent to the lower layers of the protocol stack for transmission over the network.
The “network” layer is responsible for routing data packets between networks using the Internet Protocol (IP). This layer handles tasks such as packet addressing and routing, fragmentation and reassembly, and network congestion control.
Fault Tolerance
Watch both Daily videos for 4.2
- Complete the network activity, summarize your understanding of fault tolerance.
Fault tolerance is the internet’s ability to function properly even when there is failure in hardware or software. This is achieved through redundancy and other error-solving methods that allow the system to identify and correct errors, ensuring that the performance is impacted minimally.
Parallel and Distributed Computing
Review previous lecture on Parallel Computing and watch Daily vidoe 4.3. Think of ways to make something in you team project to utilize Cores more effectively. Here are some thoughts to add to your story of Computers and Networks…
- What is naturally Distributed in Frontend/Backend archeticture?
The frontend/backend architecture is a distributed system where the frontend and backend components are naturally separated. The frontend handles the user interface and is distributed across multiple clients, while the backend handles business logic and data storage and is deployed on servers or cloud platforms. The distributed nature of the architecture provides scalability, fault tolerance, and performance optimization by adding more clients or instances for the frontend, more servers or services for the backend, replicating the backend, or load balancing. It is a popular and effective way of building modern web applications capable of handling large volumes of users and data.
- Analyze this command in Docker:
ENV GUNICORN_CMD_ARGS="--workers=1 --bind=0.0.0.0:8086"
. Determine if there is options are options in this command for parallel computing within the server that runs python/gunicorn. Here is an article
The --workers
option in the GUNICORN_CMD_ARGS
environment variable specifies the number of worker processes that Gunicorn
should spawn to handle incoming requests. Gunicorn
uses a single worker process
, which can handle only one request at a time. By increasing the number of worker processes, Gunicorn
can handle multiple requests simultaneously, which can improve the overall performance of the server.
Last week we discussed parallel computing on local machine. There are many options. Here is something to get parallel computing work with a tool called Ray.
- Review this article… Can you get parallel code on images to work more effectively? I have not tried Ray.
- Code example from ChatGPT using squares. This might be more interesting if nums we generated to be a lot bigger.
import ray
# define a simple function that takes a number and returns its square
def square(x):
return x * x
# initialize Ray
ray.init()
# create a remote function that squares a list of numbers in parallel
@ray.remote
def square_list(nums):
return [square(num) for num in nums]
# define a list of numbers to square
nums = [1, 2, 3, 4, 5]
# split the list into two parts
split_idx = len(nums) // 2
part1, part2 = nums[:split_idx], nums[split_idx:]
# call the remote function in parallel on the two parts
part1_result = square_list.remote(part1)
part2_result = square_list.remote(part2)
# get the results and combine them
result = ray.get(part1_result) + ray.get(part2_result)
# print the result
print(result)