Module_11_Study_Questions

11.1 - Networking Overview

Role of Host Devices in a Peer-to-Peer Network

• Host devices in a peer-to-peer network act as both clients and servers, directly facilitating resource exchanges without the need for a centralized server. This decentralization contributes to fostering a robust network environment where resources are readily available to all participants.

• Each device within a peer-to-peer network possesses equal capabilities, allowing for balanced resource allocation and reducing the dependency on a singular point of failure.

Benefits of Implementing a Network

• Resource Sharing: Enables multiple users or devices to access shared resources such as files, printers, and other digital assets, fostering collaborative work environments.

• Centralized Data Storage: Simplifies data management and retrieval by centralizing information that can be securely accessed by authorized users, thus enhancing data integrity and reducing redundancy.

• Improved Communication: Enhances connectivity and information flow among users, utilizing various communication tools that facilitate effective teamwork.

• Cost Efficiency: Reduces operational costs by maximizing shared resources, which decreases duplication of equipment and minimizes overall resource expenditure.

• Enhanced Collaboration: Facilitates teamwork by allowing simultaneous access to shared documents and applications, enabling real-time collaboration among users, irrespective of their geographical location.

• Centralized Backup: Simplifies the backup process, allowing organizations to easily protect critical data, ensuring business continuity and data recovery options are in place.

Determining Network and Host ID in IPv4 Address

• Subnet Mask: This is a crucial component used to determine which part of the IP address designates the network ID and which part identifies the host ID. It operates by efficiently segregating different networks.

• Network ID: Represented by bits set to 1 in the subnet mask; it defines the specific network to which the IP address belongs.

• Host ID: Represented by bits set to 0 in the subnet mask; it uniquely identifies a device within the specified network.

Type of Network with Wireless Earbuds and Cell Phone

• Personal Area Network (PAN): This type of network utilizes Bluetooth technology to create a short-range, point-to-point connection, ideally suited for connecting devices such as wireless earbuds to a mobile phone.

Device Connecting Multiple Networks

• Router: Serves as a mediator connecting different networks and managing traffic between them. It plays a critical role in forwarding data packets between networks, translating IP addresses, and providing security features such as firewalls.

11.2 - Networking Ports & Protocols

Difference Between TCP and UDP

• TCP (Transmission Control Protocol): A connection-oriented protocol that establishes a reliable connection by ensuring that packets are delivered in the correct order and that no packets are lost during transmission. This reliability is vital for applications that require data integrity, such as file transfers and web browsing.

• UDP (User Datagram Protocol): A connectionless protocol designed for fast transmission of data without the overhead of establishing a reliable connection. It is suited for applications that prioritize speed over reliability, such as video streaming and online gaming.

3-Way Handshake Steps

1. SYN: The client initiates a connection by sending a synchronize packet to the server.

2. SYN-ACK: The server acknowledges this request by sending back a synchronization acknowledgment packet.

3. ACK: The client then sends back an acknowledgment packet confirming the connection has been established, allowing data transfer to commence.

Common Uses of UDP

• Streaming media, such as video and music, where real-time data delivery is crucial despite potential packet loss.

• Online gaming, which requires real-time interactions without delays caused by connection establishment.

• VoIP (Voice over Internet Protocol) for communication, ensuring minimal latency and high-quality voice transmission.

• DNS (Domain Name System) queries for resolving domain names into IP addresses, enabling internet connectivity.

• DHCP (Dynamic Host Configuration Protocol) to dynamically assign IP addresses to devices on a network, simplifying network management.

Email Protocols

• SMTP (Simple Mail Transfer Protocol): The standard protocol used for sending emails, operating on Port 25, providing a mechanism for transferring messages between email servers.

• POP3 (Post Office Protocol): Enables users to retrieve emails from a server, operating on Port 110. It typically downloads and, in many configurations, removes messages from the server.

• IMAP (Internet Message Access Protocol): Also used for retrieving emails, operating on Port 143, but allows users to manipulate their inboxes on the server, facilitating multi-device access and email management.

Port for HTTPS

• HTTPS (Hypertext Transfer Protocol Secure): Utilizes Port 443 to ensure encrypted and secure communications over the internet, protecting user data during transactions and maintaining privacy.

11.3 - Client-Side Network Configuration

Numbering Systems in Computing

• Binary (Base-2): The fundamental numbering system utilized by computers, consisting solely of 0s and 1s, reflecting the binary nature of computing hardware.

• Hexadecimal (Base-16): Comprises values from 0-9 and A-F, providing a more compact representation of binary data, making it easier for humans to interpret.

Physical vs Logical Addresses

• Physical Address (MAC Address): A hardware-based address that is unique to each device's network interface card, facilitating device identification on a local network.

• Logical Address (IP Address): A software-assigned address that can vary depending on network configuration and connectivity, providing routing capabilities over the internet.

IPv4 Address Length

• An IPv4 address consists of 32 bits, structured as four 8-bit octets (e.g., 192.168.1.1), representing a unique address within the IPv4 network space.

IPv6 Address Length

• An IPv6 address is significantly longer at 128 bits, divided into eight 16-bit sections (e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334), allowing for an immense number of unique addresses to accommodate the growing number of internet-connected devices.

Shortening IPv6 Addresses

• IPv6 addresses can be shortened by removing leading zeros and utilizing the double colon (::) to replace consecutive zero sections, with the stipulation that :: can only be used once per address to avoid ambiguity.

11.4 - Services Provided by Network Devices

Server Resource Access

• Servers can provide access to a variety of network resources, including:

  • File storage for data sharing and collaboration.

  • Printers for shared printing resources among network users.

  • Applications allowing users to run software remotely.

  • Database access for storing and retrieving data efficiently.

  • Email services to facilitate communication within and outside organizations.

  • Web hosting for creating and managing websites on the internet.

Fully Qualified Domain Name (FQDN)

• Components of FQDN:

  • Hostname (e.g., www): Specifies the host within a domain.

  • Domain Name (e.g., example): Indicates the domain the host belongs to.

  • Top-Level Domain (e.g., .com): Classifies the domain into a category.

• Example: www.example.com represents a complete address for a specific resource on the internet.

Internet of Things (IoT)

• Definition: A network of interconnected smart devices that possess the capability for Internet connectivity, enabling them to communicate and exchange data with each other.

• Characteristics: Everyday objects equipped with sensors, software, and processors that allow for data collection, monitoring, and control, significantly enhancing efficiencies and user experiences in various applications.

11.5 - Wireless Networking

IEEE Standard for Wireless Networks

• 802.11 Standards: Defines the operation of wireless networks, with multiple versions including a/b/g/n/ac/ax, each offering varying speeds, ranges, and features to enhance wireless connectivity.

Non-Overlapping Channels

• In the 2.4 GHz frequency range, there are three primary channels (1, 6, 11) that do not overlap, minimizing interference between wireless devices.

• In the 5 GHz frequency range, there are 23 channels available, with variability depending on regional regulations, providing greater options for reducing interference and improving performance.

WPA2 Encryption Algorithm

• Utilizes the AES (Advanced Encryption Standard) with a 128-bit encryption key, offering a secure method for protecting wireless networks against unauthorized access and ensuring data privacy during transmission.

Wireless Access Method

• WPS (Wi-Fi Protected Setup): A convenient method allowing devices to connect easily to a wireless network, typically through a physical button press or a PIN entry, simplifying the process for users without extensive technical knowledge.

11.6 - SOHO Configuration

First Configuration Change on a New Wireless Router

• The initial configuration change should involve modifying the default admin password to improve security and prevent unauthorized access, thereby protecting the network from potential threats and breaches.

Authentication Protocol by DSL Providers

• PPPoE (Point-to-Point Protocol over Ethernet): The standard authentication method employed by DSL providers, typically requiring users to enter a username and password to establish internet connectivity and secure user sessions.

Technology Sharing Public IP Address

• NAT (Network Address Translation): This technology allows multiple devices connected to a private network to share a single public IP address by dynamically converting private addresses to public ones, facilitating efficient use of limited IP address resources.

Universal Plug and Play (UPnP) Feature

• Facilitates automatic port forwarding, device discovery on the network, and simplifies configuration of devices, enabling seamless connectivity and collaboration within the local network.

11.7 - Networking Hardware

Device Connecting Two Networks

• Router: A device that connects different networks and efficiently manages traffic flow between them, implementing routing protocols to ensure optimal data transfer paths, enhancing network performance and reliability.

Difference Between Hub and Switch

• Hub: Operates at the physical layer, broadcasting data to all connected ports, resulting in less efficient network performance due to potential collisions.

• Switch: Functions at the data link layer, intelligently directing data to specific destinations based on MAC addresses, thus improving network efficiency and reducing data transmission conflicts.

Power Over Ethernet (PoE) Standards

• IEEE 802.3bt (PoE++): The latest standard capable of delivering up to 100 watts of power, accommodating a wide range of devices such as IP cameras, wireless access points, and VoIP phones, enhancing the flexibility of network infrastructure.

11.8 - Command Line Network Utilities

Network Utility for Current IP Configuration in Linux

• ifconfig: Traditionally used in older systems for viewing and configuring IP settings, while newer systems now utilize ip addr for a more comprehensive approach to managing network configurations.

Utility for Testing Connection Between Devices

• ping: A critical utility used to establish connectivity and measure response time between two devices, providing insight into network performance and reliability.

Utility for Displaying Network Path

• traceroute (Linux/Mac) or tracert (Windows): Utilities that reveal the path and number of hops a packet takes through a network, assisting in diagnosing connectivity issues and understanding network topology.