How Do You Interact with a Network?

How Do You Interact with a Network?

A network is a system comprising two or more devices interconnected via wires, cables, or a telecommunications system. Networks facilitate the sharing of resources like hardware, software, data, and information among connected devices. They require a combination of hardware and software to function and serve as a global communication system through the Internet.

Digital communications refers to the process by which two or more computers or devices transfer data, instructions, and information. All types of computers and mobile devices act as both sending and receiving devices in a communication system.

Communication System Components 📡

Communication devices, such as modems, wireless access points, and routers, are essential for network operation. Transmission media can be either wired or wireless.

Types of Networks

Home Networks 🏠

Home networks enable:

• Multiple users to share a single Internet connection.

• Sharing of files (e.g., photos) among computers.

• Sharing of a single hardware resource, like a printer.

• Online gaming through connected game consoles.

Business Networks 🏢

Business networks offer advantages such as:

• Facilitating communication among employees.

• Sharing hardware like printers and scanners.

• Sharing data, information, and software.

• Centrally storing and backing up critical information.

Specialized Business Networks

• Intranet: An internal network that utilizes Internet technologies, accessible only from within an organization.

• Extranet: Allows external parties, such as customers or suppliers, to access a part of an organization's intranet.

• VPN (Virtual Private Network): Enables individuals to securely access an organization's network by using encryption and other technologies to protect data in transit.

Wired vs. Wireless Networks

Wired Networks

• Transmit signals and data through physical cables, often installed within walls and floors, to connect devices.

• Generally offer higher security and faster data transfer speeds compared to wireless networks.

Wireless Networks

• Transmit signals via airwaves, typically without requiring physical cables.

• Can be less secure but provide greater convenience and ease of setup.

• Cellular Network (Mobile Network): A communication network where connections to and from end nodes are wireless. Examples include 3G, 4G, and 5G.

Communications Software

This includes programs and apps that:

• Help users connect to other computers, mobile devices, or networks.

• Manage the transmission of data, instructions, and information.

• Provide an interface for user communication.

Network Structures

Networks can be categorized by their topology, architecture, and geographic reach.

• Topology: Refers to the physical arrangement of computers and devices on a network.

• Network Architecture: Describes the logical design, including the roles of servers and users.

• Geographic Reach: Determines the span of the network.

Common network topologies include bus, ring, star, and mesh networks.

Network Topologies 🌐

Network Architectures

Client/Server Network

• One or more computers function as servers, providing resources to other computers or mobile devices called clients.

• Clients rely on the server for their resources.

• Controlled by a network administrator.

Peer-to-Peer (P2P) Network

• Connects a small number of computers (typically fewer than 10).

• Computers communicate directly with each other and share resources.

• All computers are treated equally; no network administrator is needed.

• Internet P2P networks allow users to share files directly over the Internet, though sharing copyrighted files is illegal.

Network Geographic Reach

Network configurations vary in size, defined by the number of devices and their geographic span.

• LAN (Local Area Network): Connects computers and devices within a limited physical area.

• WLAN (Wireless LAN): A LAN that uses wireless connections.

• WAN (Wide Area Network): Connects devices across a large geographic region.

• MAN (Metropolitan Area Network): A type of WAN operated by a city or county.

• PAN (Personal Area Network): Connects personal digital devices via technologies like Bluetooth (e.g., a smartwatch).

• BAN (Body Area Network): A PAN consisting of small, lightweight biosensors implanted in the body.

Network Standards and Protocols

A protocol defines aspects such as data format, coding schemes, error handling, and the sequence of data transfer over a network.

TCP/IP (Transmission Control Protocol/Internet Protocol)

• A common family of protocols.

• TCP: Defines how data is routed through a network.

• IP: Specifies that all connected computers and devices have a unique IP address.

• Two types: IPv4 and IPv6.

Wireless Network Protocols

These support close-distance communication and include standards such as:

• Wi-Fi

• LTE

• Bluetooth

• UWB

• IrDA

• RFIC

• NFC

Wi-Fi

• Enables wireless communication between computers or devices via radio waves using 802.11 standards.

• 802.11: A series of network standards developed by the IEEE.

• Common standards include 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, and 802.11ax, with data transfer rates from 11 Mbps to 7 Gbps.

• Devices often support multiple standards (e.g., 802.11ac/b/g/n/ac/ax).

• Wi-Fi networks can be integrated with wired Ethernet networks.

• Extra hardware may be needed to extend or strengthen wireless signals.

Bluetooth

• A network protocol defining how two Bluetooth devices use short-range radio waves to transmit data (up to 3 Mbps).

• Bluetooth devices contain a small chip for communication.

• Devices are initially connected using a code and are then said to be "paired."

• Uses include:

• Connecting to vehicle stereos for sound projection.

• Sending GPS directions to mobile phones.

• Wirelessly transferring photos from digital cameras.

• Replacing wired communication devices like barcode readers for enhanced portability.

Network Connection Hardware

• Nodes: Any device on a network, including computers, tablets, mobile phones, printers, game consoles, or smart home devices.

• Hubs: Provide a central point for network cables and send data to all connected devices.

• Switches: More commonly used than hubs, they also provide a central point but send data only to the intended recipient.

• Routers: Connect two or more networks and direct the flow of information between them.

• Modems: Connect a sending or receiving device (e.g., computer) to a communications channel (e.g., the Internet) via an ISP.

• Digital modem (broadband modem): Sends and receives data to/from a digital line. Types include cable modems, DSL modems, and ISDN modems.

How To: Set Up a Network

Setting Up a Home Wireless Network

A simple home network can be two devices connected by a cable. An Internet-connected wireless home network requires:

• A modem

• A router

• A wireless access point

• Devices to be connected

Installation depends on hardware, home size, and devices to be connected.

Steps to Set Up a Network

1. Purchase and Connect Modem/Router: Buy a modem or separate wireless router and connect it to your home's Internet service.

2. Enable Wireless Network:

• Configure a name (SSID) for the network.

• Configure a wireless network key (password).

3. Connect Devices:

• Enable the device's wireless functionality.

• Search for and connect to the wireless network name specified in Step 2.

• Enter the wireless network key.

Adding a Wireless Printer

Advantages include multiple computers and mobile devices using the printer. Manufacturers often provide apps for sending documents.

Steps to Add a Wireless Printer

• Place the printer within the wireless network's range on a stable surface.

• Access the printer's settings and navigate to network settings.

• Connect to the wireless network in your home or office.

• Enter any remaining required information.

• Install the printer app on devices that will print to it.

Improving Wireless Signal Strength

• Extend antenna(s) on wireless router/access point.

• Replace removable antennas with a wireless signal booster.

• Place the wireless router/access point in a central location.

• Purchase a booster (repeater) to amplify and extend range.

• Change the router if problems persist.

Secure It: Secure a Network

Wireless networks are easily accessible and prone to risks.

Network Security Measures

• Change default password for wireless access point, SSID name, encryption settings, and MAC address filtering.

• Regularly check the number of connected devices to the wireless router.

Common Network Risks 🛡

Network Security Tools

• Encryption: Scrambles or codes data transmitted over a network.

• Network Attached Storage (NAS): Provides centralized storage for programs and data on networks.

• Authentication: Identifies users to the network, commonly via username and password.

• Firewalls: Create a barrier between corporate/personal networks and the Internet.

• Biometric Devices: Authenticate identity by scanning physical characteristics (e.g., fingerprint).

• Network Monitoring Software: Assesses network status, alerts administrators to problems, measures traffic, graphs usage, and shows bandwidth consumption.

• Packet Sniffer Software: Monitors and logs packet traffic for analysis; can be used by hackers to hijack computers.

Detecting Unauthorized Access

1. Sign in to the administrative interface of your router.

2. Count the number of connected devices.

3. Secure the network (e.g., change passwords).

4. Enable the router's firewall and use "stealth mode" to make the network less visible.

Ethics and Issues: Responsibilities of a Network Professional

Role of a Network Administrator

A network administrator's role involves:

• Planning, designing, and purchasing equipment for a network.

• Setting up, securing, and maintaining the network.
  USENIX is a non-profit organization supporting network and system engineers in innovation and research since 1975.

Ethical Guidelines for Network Professionals

A code of ethics for network professionals includes guidelines for:

• Professionalism

• Social Responsibility

• Personal Integrity

• Privacy

• Compliance with Laws and Policies

• Communication

• System Integrity

• Education

• Responsibility to the Computing Community

• Ethical Responsibility