OpenLLM-France/wikimedia huggingface dataset:
# Web Science/Part1: Foundations of the web/Internet Architecture/Ethernet

* PART1: Week1: Ethernet · Internet Protocol · Week2: Transmission Control Protocol · Domain Name System · Week3: Internet vs world wide web · HTTP · Week4: Web Content · Dynamic Web Content
* PART2: Week5: How big is the Web? · Descriptive Web Models · Week6: Advanced Statistic Models · Modelling Similarity · Week7: Generative Modelling of the Web · Graph theoretic Web Modelling
* PART3: Week8 : Investigating Meme Spreading · Herding Behaviour · Week9: Online Advertising · User Modelling
* PART4: Week10 : Copyright · Net neutrality · Week11: Internet governance · Privacy
| Video and script | Associated Lesson |
| | Communication over a shared Medium |
| | Ethernet Header |
| | Minimum Package length vs Maximum cable length |
| | Collision Detection |
| no video | Summary, Further readings & Homework |
The following video of the flipped classroom associated with this topic are available:
You can find more information on wiki commons and also directly download this file
# Teletraffic engineering/What is Congestion control?

originally written by Moses Chisala

## Summary

The document defines congestion control and the five algorithms found in the TCP protocols: slow start Exponential backoff, sliding window, Fast retransmit and Fast recovery. In addition, it also gives an example and an exercise basing on simple “steady-state model” of TCP technique.

## Definition

Congestion control is a method used for monitoring the process of regulating the total amount of data entering the network so as to keep traffic levels at an acceptable value. This is done in order to avoid the telecommunication network reaching what is termed w:congestive collapse.
Congestion control mostly applies to packet-switching network. A wide variety of approaches have been proposed, however the "objective is to maintain the number of packets within the network below the level at which performance falls off dramatically."
There are two transport layer protocols where congestion control is implemented;
* Transmission Control Protocol
* User Datagram Protocol
In the TCP there are several congestion control algorithms strateges used:
* slow start
* exponential backoff

## Model: The simple “steady-state model” of TCP

* Fixed roundtrip time R in seconds.
* A packet is dropped each time the window reaches W packets.
* TCP’s congestion window: W, W / 2, W / 2 + 1,..., W - 1, W, W / 2
The average sending rate T pkts per sec: T = 3W / 4R
The packet drop rate p: p = 1 / (⅜ * W²)
T in pkts per sec: T = √(3 / 2) / (R * √p)
or in bytes per sec, given B bytes per pkt: T = √(3 / 2) * B / (R * √p)
The improved “steady-state model” of TCP:
An improved steady-state model of TCP includes a fixed packet drop rate,retranmit timeouts, and the exponential backoff of the retransmit timer.
T = B / [R * √(2 * p / 3) + 2 * R * {3 * √(3 * p / 8)} * p * (1 + 32 * p²)]

### T

    sending rate in bytes/sec

### B

    packet size in bytes

### R

    roundtrip time

### p

    packet drop rate[1]
* sliding window
* fast retransmit
* fast recovery

### Example

The date rate between two routers is 230.4 Kbps, and the TCP congestion window is 30 packets. calculate the round trip time R. (Assuming 1 packet = 512 - bytes)

#### Solution
## Exercises

An internet cafe connects to an ISP with bandwidth of 10 Mbps. The TCP’s congestion window is 64 KB. (1 packet = 512 bytes)
* Calculate the round trip time at network equilibrum
* What is the packet drop rate?
* What is the capacity of the TCP’s congestion window packets?
Solutions
# Network+/Architecture/Services/Reverse Proxy

w:Reverse proxy is a type of proxy server that retrieves resources on behalf of a client from one or more servers.

### Activities

* Review list of available proxy servers
# Network+/Old guides/OSI Model/OSI Components

This table shows the OSI model layers and the components that operate at each layer.
| OSI Layer | Purpose | TCP/IP Layer | Protocol | Packet Data Unit | Address | Device | Troubleshoot |
| Application | Interface (API) | Application | HTTP, SMTP, etc. | Message | - | - | Wireshark |
| Presentation | Formatting, Encryption, Compression | Application | HTTP, SMTP, etc. | Message | - | - | Wireshark |
| Session | Authentication, Authorization | Application | HTTP, SMTP, etc. | Message | - | Gateway | NSLOOKUP, NBTSTAT, Wireshark |
| Transport | Reliability | Transport | TCP, UDP | Segment (TCP), Datagram (UDP) | Port | Firewall | TELNET, NETSTAT, Wireshark |
| Network | Addressing, Routing | Internet | IP, ICMP | Packet | IP Address | Router | IPCONFIG, PING, TRACERT, Wireshark |
| Data Link | Logical Link Control, Media Access Control | Link | Ethernet, Wi-Fi, PPP, etc. | Frame | MAC Address | Switch, Bridge, Access Point | Lights on device, ARP, Wireshark |
| Physical | Transmission | Link | CAT 5, RJ-45, etc. | Bit | - | Hub, NIC, Cable, Wireless | Lights on device |
One easy way to remember the OSI layer is to think:[source?]
A - All
P - People
S - Seem
T - To
N - Need
D - Data
P - Processing
Another popular acrostic to remember OSI layers names is (inferring that it is required to attend classes to pass networking certification exams):
A - Away
P - Pizza
S - Sausage
T - Throw
N - Not
D - Do
P - Please
Suggestions from David Bombal (7 to 1):
A - All
P - People
S - Sleeping
T - Through
N - Networking
D - Don't
P - Pass
Going the opposite way (1-7):
P - Please
D - Do
N - Not
T - Teach
S - Students
P - Pointless
A - Acronyms
Going the opposite way, widely used in India Schools (1-7):
P - Please
D - Do
N - Not
T - Take
S - Sales
P - Person's
A - Advice
# Network+/Activities

* Test your internet connection using any of the public available services: fast.com or speedtest.net.
** Install and test speedtest-cli, Speedtest.net's command-line interface.
* Browse Review list of available proxy servers
* Work through the following activities on networking tools taken from the Computer Networks resource.
** Arp
** Ipconfig
** Nbtstat
** Netstat
** Nslookup
** Ping
** Route
** Tracert
# Cisco Networking

Cisco networking includes a variety of computer networking concepts, including network operations, switching, routing, security, and wide area networks based on Cisco Systems devices and Cisco IOS.

## Courses

* CCENT
* CCNA
* CCNA Voice
* CCNP
* CCVP

## See Also

* Wikipedia: Cisco Systems
* Cisco IOS
# Network Classifications

Topic:Computer networks : Network Classifications
Computer networks are typically classified by scale, ranging from small, personal networks to global wide-area networks and the Internet itself. The following readings provide detailed information on the common network classifications:
* Wikipedia: Computer Network - Scale
* Wikipedia: Personal Area Network (PAN)
* Wikipedia: Storage Area Network (SAN)
* Wikipedia: Local Area Network (LAN)
* Wikipedia: Campus Area Network (CAN)
* Wikipedia: Metropolitan Area Network (MAN)
* Wikipedia: Wide Area Network (WAN)
# Teletraffic engineering

The Teletraffic Hyperlinked Textbook
This is the combined work of the ELEN5007 class of 2007 (now ELEN7015).

## Modules

* What is Blocking?
* What are the types of Congestions?
* What is Congestion control?
* What is the Engset calculation?
* What is Flow control?
* What are Gradings?
* What_is_the_High_loss_calculation?
* How does Internet telephony traffic differ?
* What is the limited availability calculation?
* What is Long-tailed traffic? (6 modules=1course)*
* What is Mobile Quality of Service? (1 module)*
* What is Multi-media traffic? (1 module)*
* What is Quality of Service? (1 module)*
* What is queueing?
* What is Routing?
* What is tariffing?
* What is Trade in Services?
* How do we Manage Teletraffic data?
* How is Telephony Traffic Forecast?
* How is Telephony Traffic Modelled?
* How is telephony traffic simulated?
* What is Trunking?
* Existing modules (ca. 2006), to be imported from cnx.org

## Contributors

| Name | email | modules |
| Ian Kennedy | dr.iankennedy at gmail.com | Editor in Chief |
| Jorenjeye Arubayi 0705588N | lasborn at yahoo.co.uk | Module 15. What is routing?, Module 20. How is Telephony Traffic Modelled? |
| Chilekwa Bwalya 0701344F | chilekwab at hotmail.com | Module 8. How does Internet telephony traffic differ? Module 14. What is Queueing? |
| Nosipho Dhladhla 0705577P | mnorid at yahoo.com | Module 4. What is the Engset calculation? Module 17. What is Trade in Services? |
| Nomfundo Dlamini 0607335G | dlamini at volt.ee.wits.ac.za | Module 1. What is Blocking? Module 21. How is telephony traffic simulated? |
| Daniel Enslin 0008750T | bestbuddy69 at hotmail.com | Module 6. What is Grading? Module 19. How is Telephony Traffic Forecast? |
| Chisala Moses 0700386W | moseslsa at yahoo.com | Module 3. What is Congestion control? Module 16. What is tariffing? |
| Michel Le Vieux 9408490D | michel at mtnns.net | Module 5. What is Flow control? Module 22. What is Trunking? |
| Stephen kyalo Musango Makonge 0710458J | steve at integritylimited.ws | Module 7. What is the High loss calculation? Module 9. What is the Limited Availability Calculation? |
# UML/OSI

OSI Model :
| | Data unit | Layer | Function |
| Host layers | Data | 7. Application | Network process to application |
| Host layers | Data | 6. Presentation | Data representation and encryption |
| Host layers | Data | 5. Session | Interhost communication |
| Host layers | Segment | 4. Transport | End-to-end connections and reliability |
| Media layers | Packet | 3. Network | Path determination and logical addressing |
| Media layers | Frame | 2. Data Link | Physical addressing |
| Media layers | Bit | 1. Physical | Media, signal and binary transmission |
The OSI model can be used to conceptualize complex networks of people, places, and machines. UML diagram elements can be structured in layers that correspond to the 7-layer OSI model. Currently there is growing interest in the use of UML for system modeling. Structuring specifications is difficult, but The ITU (International Telecommunications Union), the IEC (International Electrotechnical Commission) and the ISO have jointly defined some UML profiles for a Reference Model of Open Distributed Processing (RM-ODP).

## Physical

Media, signal and binary transmission
Protocols: RS-232, V.35, V.34, I.430, I.431, T1, E1, 802.3 Ethernet, 10BASE-T, 100BASE-TX, POTS, SONET, DSL, 802.11a/b/g/n PHY, ITU-T G.hn PHY

## Data Link

Physical addressing
Protocols: ARP, CSLIP, SLIP, Frame Relay, ITU-T G.hn DLL

## Network

Path determination and logical addressing
Protocols: IP, ICMP, IPsec, IGMP

## Transport

End-to-end connections and reliability
Protocols: TCP, UDP, PPTP, L2TP, SCTP

## Session

Interhost communication
Protocols: Named Pipes, NetBIOS, SAP

## Presentation

Data representation and encryption
Protocols: MIME, XDR, SSL, TLS

## Application

Network process to application
Protocols: NNTP, SIP, SSI, DNS, FTP, Gopher, HTTP, NFS, NTP, SMPP, SMTP, SNMP, Telnet, (more)

## notes

* ↑ A Layered Approach to Information Modeling and Interoperability on the Web 2000 - Melnik, Decker, Database Group, Stanford University
* ↑ X.906 : UML4ODP - Use of UML for ODP system specifications ITU Recommendation X.906 (11/07) itu subscription version
# Network+

Network+ is a CompTIA computer networking certification that includes computer network concepts, installation and configuration, media and topologies, management, and security.
This resource features a combination of Wikipedia readings, YouTube videos, and hands-on learning activities as a study guide to prepare for CompTIA Network+ Certification.

## Preparation

Learners would be best served by first approaching computer support concepts.

## Objectives

See list of all objectives. For each domain:
* Networking Concepts
* Network Implementation
* Network Operations
* Network Security
* Network Troubleshooting
Also see list of acronyms and technologies .

## Test Details

Exam description:
   The CompTIA Network+ certification verifies that the successful candidate has the knowledge and skills required to:
   * Establish network connectivity by deploying wired and wireless devices.
   * Understand and maintain network documentation.
   * Understand the purpose of network services.
   * Understand basic datacenter, cloud and virtual networking concepts.
   * Monitor network activity, identifying performance and availability issues.
   * Implement network hardening techniques.
   * Manage, configure, and troubleshoot network infrastructure.
Number of questions: Maximum of 90
Length of test: 90 minutes
Passing score: 720 (on 100-900 scale)
Recommended experience:
   CompTIA A+ certification and a minimum of 9-12 months of hands-on experience working in a junior network administrator/network support technician job role.
Exam code: N10-009
Languages: English, Japanese, German, Spanish, (Portuguese to follow)

## Guides

These are compiled resources to help familiarize learners with Network+ concepts. Feel free to add relevant material (with caution for copy violations - Wikipedia may be freely copied with attribution).
* Further reading
* Activities

### Old guides

These were made for a previous version of the exam, and may contain outdated material.
* Routing
* Ethernet
* Network media
* OSI Model
* IP Model

## External Links

* Cybrary: CompTIA N10-009 Network+ Course
* Professor Messer’s CompTIA N10-009 Network+ Training Course
# Network+/Architecture

This section of the computer networks course covers devices, remote access, services, WAN technologies, media, topologies, infrastructure, addressing, routing, unified communications, virtualization and cloud, and implementation.

## Preparation

Learners should already be familiar with network fundamentals.

## Lessons

* Devices
* Remote Access
* Services
* WAN Technologies
* Media
* Topologies
* Infrastructure
* Addressing
* Routing
* Unified Communications
* Virtualization and Cloud
* Implementation

## See Also

* IC$^3$ - Network Fundamentals
# Network+/Operations

This section of the computer networks course covers monitoring, performance, configuration management, segmentation, updates, switching, and wireless.

## Preparation

Learners should already be familiar with network architecture.

## Lessons

* Monitoring
* Performance
* Configuration Management
* Segmentation
* Updates
* Switching
* Wireless

## See Also

* IC$^3$ - Network Fundamentals
# Network+/Security

This section of the computer networks course covers risk, threats, hardening, physical security, firewalls, access control, and forensics.

## Preparation

Learners should already be familiar with network architecture and network operations.

## Lessons

* Risk
* Threats
* Hardening
* Physical Security
* Firewalls
* Access Control
* Forensics

## See Also

* IC$^3$ - Network Fundamentals
# Network+/Troubleshooting

This section of the computer networks course covers troubleshooting methodology, tools, wireless issues, copper issues, fiber issues, network issues, security issues, and WAN issues.

## Preparation

Learners should already be familiar with network architecture and network operations.

## Lessons

* Methodology
* Tools
* Wireless Issues
* Copper Issues
* Fiber Issues
* Network Issues
* Security Issues
* WAN Issues

## See Also

* IC$^3$ - Network Fundamentals
# Network+/Standards

This section of the computer networks course covers the OSI model, theory and concepts, wireless, wired, policies and procedures, safety practices, equipment placement, change management, protocol concepts, and protocol usage.

## Preparation

Learners should already be familiar with network fundamentals.

## Lessons

* OSI Model
* Theory and Concepts
* Wireless
* Wired
* Policies and Procedures
* Safety Practices
* Equipment Placement
* Change Management
* Protocol Concepts
* Protocol Usage

## See Also

* IC$^3$ - Network Fundamentals
# IT Security/Network

This section of the IT security course covers devices, network administration, network design, protocols, and wireless security.

## Preparation

Learners should already be familiar with introductory computer concepts, computer support concepts, and computer networking concepts.

## Lessons

* Devices
* Administration
* Design
* Protocols
* Wireless

## See Also

* Computer Networks/Security
# IT Security/Operational

This section of the IT security course covers operational risk, integration, mitigation, forensics, incident response, training, physical security, best practices, and control.

## Preparation

Learners should already be familiar with introductory computer concepts, computer support concepts, and computer networking concepts.

## Lessons

* Risk
* Systems Integration
* Risk Mitigation
* Forensics
* Incident Response
* Training
* Physical Security
* Best Practices
* Controls
# IT Security/Threats

This section of the IT security course covers threats, including malware, attacks, social engineering, wireless, application, mitigation, tools, and testing.

## Preparation

Learners should already be familiar with introductory computer concepts, computer support concepts, and computer networking concepts.

## Lessons

* Malware
* Attacks
* Social Engineering
* Wireless Attacks
* Application Attacks
* Threat Mitigation
* Tools
* Testing
# IT Security/Host

This section of the IT security course covers host security, including application, mobile, host, data, and environmental mitigation.

## Preparation

Learners should already be familiar with introductory computer concepts, computer support concepts, and computer networking concepts.

## Lessons

* Application
* Mobile
* Host
* Data
* Environmental Mitigation
# IT Security/Access Control

This section of the IT security course covers access control, including Authentication, Authorization, and Accounting (AAA).

## Preparation

Learners should already be familiar with introductory computer concepts, computer support concepts, and computer networking concepts.

## Lessons

* Authentication Services
* Authentication and Authorization
* Account Management

## See Also

* IAM Identity and Access Management
# IT Security/Cryptography

This section of the IT security course covers cryptography, including concepts, methods, and PKI.

## Preparation

Learners should already be familiar with introductory computer concepts, computer support concepts, and computer networking concepts.

## Lessons

* Concepts
* Methods
* PKI
# Wiki gaming

Wiki gaming is the use of wikis as a platform for a game.

## Wikipedia game pages

(See Category:Wikipedia games)
* Portal:India/Quiz: Quiz game about India
* Wikipedia:WikiRPG currently defunct role playing game to encourage wikipedia editing
* Wikipedia:Trading card game current Wikipedia card trading game

## External Wikipedia game sites

* The Wiki Game: Explore and race through Wikipedia articles!
# 1000 Songs/Oxyrhynchus hymn fragment

Oxyrhynchus hymn fragment
1000 Songs

## Text
### Author

Although the author of this particular papyrus fragment is unknown, it was likely written by someone who was in Oxyrhynchus at the same time as authors of the other Oxyrhynchus papyrus fragments, such as Alcaeus.

### Translations/Challenges

The original language of this hymn is Greek. The brackets denote reconstructed areas of the text.
Spoken: [Σε Πάτερ κόσμων, Πάτερ αἰώνων, μέλπωμεν] ὁμοῦ, πᾶσαι τε Θεοῦ λόγιμοι δο[ῦλο]ι. Ὅσα κ[όσμος ἔχει πρὸς ἐπουρανίων ἁγίων σελάων.]
Sung: [Πρ]υτανήω σιγάτω, μηδ' ἄστρα φαεσφόρα λ[αμπέ]
Spoken: σθων, [ἀπ]ολει[όντων] ῥ[ιπαὶ πνοιῶν, πηγαὶ]
Sung: ποταμῶν ῥοθίων πᾶσαι. Υμνούντων δ' ἡμῶν [Π]ατέρα χ' Υἱὸν χ' Ἅγιον Πνεῦμα, πᾶσαι δυνάμεις ἐπιφωνούντων· Ἀμήν, Ἀμήν. Κράτος, αἶνος [ἀεὶ καὶ δόξα Θεοὶ δωτῆρι μόνῳ πάντων] ἀγαθῶν· Ἀμήν, Ἀμήν."
A literal translation from Greek to English would read:
.. Let it be silent
Let the Luminous stars not shine,
Let the winds (?) and all the noisy rivers die down;
And as we hymn the Father, the Son and the Holy Spirit,
Let all the powers add "Amen Amen"
Empire, praise always, and glory to God,
The sole giver of good things, Amen Amen

### Editor's Choice

Let the world be silent
Let not the stars shine their lights
Calm the winds, silence the rivers
Let all praise the Father, the Son and the Holy spirit
Let all sing together Amen, Amen.
Let kings bow, and God receive the glory!
The sole giver of good things, Amen Amen.

## Music
### Tune

The original tune is in a Gregorian chant-like style, with all in unison.
The music is recorded in an archaic fashion above the lines of text on the Papyrus. This article appears to be in hypolydian mode with a final on the second scale degree, although in a more practical sense, one could argue that it truly functions in mixolydian, going outside of that range by just one note.

### Arrangements

There are few arrangements of the song. Many sing the original with the chant transposed up an octave so it can be sung by men and women in comfortable ranges.

### Editor's Choice
## Background
### Historical setting

This hymn was found with many other fragments of Papyrus in the ancient town of Oxyrhynchus. The document found in 1918 and published four years later.
Oxyrhynchus was a town down the river from Cairo where the current site of el-Bahnasa lies. The town is named after a fish that is believed to have eaten the penis of Osiris, the god of the dead.
# Improving Social Systems/Leverage Point Examples

Donella Meadows' twelve leverage points are places within a system where a small change can make a big impact. These points help us figure out where to focus efforts to influence how a system works.
Meadows ranked these leverage points from least to most powerful, meaning some are easier to change but have less effect, while others are harder to change but can transform the system significantly.
Here's a simplified overview of those leverage points:
12. Constants, Parameters, Numbers
* Example: Adjusting taxes or speed limits.
* Impact: Easy to tweak but doesn’t change the system much.
11. Sizes of Buffers
* Example: Water reserves in a city.
* Impact: Stabilizes a system but requires big infrastructure changes.
10. Material Stocks and Flows
* Example: Improving how materials move through a factory.
* Impact: Helps optimize processes but doesn’t change overall behavior.
9. Delays in Feedback Loops
* Example: Speeding up response times in a supply chain.
* Impact: Reduces inefficiencies but only improves the system’s reaction.
8. Strength of Negative Feedback Loops
* Example: Strengthening laws to prevent pollution.
* Impact: Keeps systems stable but doesn’t address root causes.
7. Positive Feedback Loops
* Example: Subsidizing renewable energy to accelerate adoption.
* Impact: Drives exponential growth but needs careful management to avoid collapse.
6. Information Flow
* Example: Making data about CO₂ emissions publicly available.
* Impact: Increases transparency and awareness, enabling better decisions.
5. Rules of the System
* Example: Changing voting laws.
* Impact: Restructures how the system operates and can shift power dynamics.
4. Power to Self-Organize
3. Goals of the System
2. Mindset or Paradigm of the System
1. Transcending Paradigms
* Example: Recognizing that all paradigms are just ideas and can be replaced.
* Impact: The ultimate game-changer, allowing complete reinvention of the system. In summary, the higher the number, the deeper the change in the system—and the harder it is to implement.