[M1-MAIN] Networking Today and Basic Switch and End Device Configuration

Host

Every computer on a network is called a host or end device.

End Device

An end device is where a message originates from or where it is received.

Client

Computers that send requests to servers to retrieve information.

Server

Computers that provide information to end devices.

Email Server

Runs email server software; clients use client software to access email.

Web Server

Runs web server software; clients use browser software to access web pages.

File Server

Stores corporate and user files, accessed by client devices.

Peer-to-Peer Network

A network design where a device can be both a client and a server, recommended only for very small networks.

Intermediary Device

A device that interconnects end devices, such as switches, wireless access points, routers, and firewalls.

Network Media

The medium through which communication across a network is carried, allowing a message to travel from source to destination.

Metal Wires within Cables

Network media type that uses electrical impulses.

Glass or Plastic Fibers within Cables (Fiber-Optic Cable)

Network media type that uses pulses of light.

Wireless Transmission

Network media type that uses modulation of specific frequencies of electromagnetic waves.

Network Diagram

Also called a topology diagram, uses symbols to represent devices within the network.

Topology Diagram

Illustrates devices and connections within a network.

Physical Topology Diagram

Illustrates the physical location of intermediary devices and cable installation.

Logical Topology Diagram

Illustrates devices, ports, and the addressing scheme of the network.

Network Interface Card (NIC)

A component used in network representations.

Physical Port

A connection point on a device used in network representations.

Interface

Often used interchangeably with "port" in network representations.

Small Home Network

Connects a few computers to each other and the Internet.

Small Office/Home Office (SOHO) Network

Enables computers within a home or remote office to connect to a corporate network.

Medium to Large Network

Many locations with hundreds or thousands of interconnected computers.

World Wide Network

Connects hundreds of millions of computers worldwide, such as the internet.

Local Area Network (LAN)

A network infrastructure that spans a small geographical area.

Wide Area Network (WAN)

A network infrastructure that spans a wide geographical area.

Internet

A worldwide collection of interconnected LANs and WANs.

IETF

A group developed to help maintain structure on the internet.

ICANN

A group developed to help maintain structure on the internet.

IAB

A group developed to help maintain structure on the internet.

Intranet

A private collection of LANs and WANs internal to an organization, accessible only to authorized members.

Extranet

Provides secure access to an organization's network for individuals from different organizations who need data access.

Broadband Cable

High bandwidth, always-on internet offered by cable television service providers.

Broadband Digital Subscriber Line (DSL)

High bandwidth, always-on internet connection that runs over a telephone line.

Wireless WAN

An internet access technology for home users and small offices.

Mobile Services

An internet access technology for home users and small offices.

Business DSL

A business-class interconnection provided by service providers.

Leased Line

A business-class interconnection provided by service providers, reserved circuits connecting distant offices.

Metro Ethernet

A business-class interconnection provided by service providers, extends LAN access technology into the WAN.

Cellular

Uses a cell phone network to connect to the internet.

Satellite

Provides internet connection in rural areas without Internet Service Providers.

Dial-up Telephone

An inexpensive, low bandwidth internet option using a modem.

Converging Network

A network that carries multiple services (data, voice, video) on one link using the same infrastructure, rules, and standards.

Network Architecture

Refers to the technologies that support the infrastructure that moves data across the network.

Fault Tolerance

A characteristic of reliable networks that limits the impact of a failure by providing multiple paths.

Scalability

A characteristic of reliable networks that allows expansion to support new users and applications without impacting performance.

Quality of Service (QoS)

The primary mechanism used to ensure reliable delivery of content for all users, especially for voice and video.

Network Security

Addresses the physical security of network devices and preventing unauthorized access to them.

Information Security

Protection of the information or data transmitted over the network.

Confidentiality

A goal of network security, ensuring only intended recipients can read the data.

Integrity

A goal of network security, assuring data has not been altered during transmission.

Availability

A goal of network security, assuring timely and reliable access to data for authorized users.

Bring Your Own Device (BYOD)

Allows users to use their personal devices (laptops, tablets, smartphones) to access information and communicate.

Online Collaboration

Working with others over the network on joint projects using tools like Cisco WebEx.

Video Communication

Using video calls and conferencing for communication, regardless of location.

Cloud Computing

Allows storing personal files or backing up data on servers over the internet, and accessing applications.

Public Cloud

Cloud type available to the general public through a pay-per-use model or for free.

Private Cloud

Cloud type intended for a specific organization or entity.

Hybrid Cloud

Made up of two or more cloud types, connected using the same architecture.

Custom Cloud

Built to meet the needs of a specific industry.

Smart Home Technology

A trend integrating technology into everyday appliances, allowing them to interconnect.

Powerline Networking

Allows devices to connect to a LAN using electrical outlets and sending data on certain frequencies.

Wireless Broadband

An option to connect homes and small businesses to the internet, often found in rural environments.

Wireless Internet Service Provider (WISP)

An ISP that connects subscribers to designated access points or hotspots.

External Threats

Security threats originating from outside the network, such as viruses, worms, Trojan horses, spyware, adware, zero-day attacks, threat actor attacks, denial of service attacks, data interception and theft, and identity theft.

Internal Threats

Security threats originating from inside the network, such as lost or stolen devices, accidental misuse by employees, and malicious employees.

Antivirus Software

A security solution installed on end devices to protect against viruses.

Antispyware Software

A security solution installed on end devices to protect against spyware.

Firewall Filtering

Used to block unauthorized access to the network.

Dedicated Firewall System

An additional security requirement for larger networks.

Access Control Lists (ACL)

An additional security requirement for larger networks.

Intrusion Prevention Systems (IPS)

An additional security requirement for larger networks.

Virtual Private Networks (VPN)

An additional security requirement for larger networks.

Operating System (OS)

Required by all end devices and network devices.

User EXEC Mode

A Cisco IOS command mode allowing access to limited basic monitoring commands, identified by >.

Privileged EXEC Mode

A Cisco IOS command mode allowing access to all commands and features, identified by #.

Global Configuration Mode

Accessed before other specific configuration modes to configure options on the device.

Line Configuration Mode

A subconfiguration mode used to configure console, SSH, Telnet, or AUX access.

Interface Configuration Mode

A subconfiguration mode used to configure a switch port or router interface.

Console

A physical management port used to access a device for initial configurations.

Secure Shell (SSH)

Establishes a secure remote CLI connection to a device over a network.

Telnet

Establishes an insecure remote CLI connection to a device over the network, sending data in plaintext.

Terminal Emulation Program

Software (e.g., PuTTY, Tera Term, SecureCRT) used to connect to a network device via console, SSH, or Telnet.

Keyword

A specific parameter defined in the operating system within a command structure.

Argument

A value or variable defined by the user within a command structure.

Context-sensitive help

An IOS help feature that allows quick finding of available commands, arguments, and keywords.

Command syntax check

An IOS help feature that verifies valid command entry and provides feedback on errors.

Tab

A hot key that completes a partial command name entry.

Backspace

A hot key that erases the character to the left of the cursor.

Left Arrow or Ctrl+B

Hot keys that move the cursor one character to the left.

Right Arrow or Ctrl+F

Hot keys that move the cursor one character to the right.

Up Arrow or Ctrl+P

Hot keys that recall commands in the history buffer.

Ctrl-C

A hot key that ends any configuration mode and returns to privileged EXEC mode.

Ctrl-Z

A hot key that ends any configuration mode and returns to privileged EXEC mode.

Ctrl-Shift-6

An all-purpose break sequence used to abort DNS lookups, traceroutes, pings, etc.

Startup-config

The saved configuration file stored in NVRAM, containing commands used upon startup or reboot.

Running-config

The current configuration stored in RAM, whose modifications immediately affect device operation.

NVRAM

Non-volatile RAM, where the startup-config is stored and retains content when powered off.

RAM

Random Access Memory, where the running-config is stored and loses content when powered off or restarted.

IP Address

The primary means of enabling devices to locate one another and establish end-to-end communication on the internet.