Vocabulary
How to Use This Glossary
This glossary contains all the important networking terms from Module 3, organized alphabetically for easy reference. Each term includes:
- Definition: What the term means in simple language
- Real-world analogy: A comparison to help you remember and understand
- Example: How you might encounter this in actual work
- Related terms: Other vocabulary that connects to this concept
A
Access Point (AP)
Definition: A network device that provides WiFi connectivity to wireless devices Real-world analogy: Like a radio tower that broadcasts and receives signals for mobile phones Example: Installing access points in different floors of an office building to provide WiFi coverage everywhere Related terms: WiFi, Wireless Network, SSID
ARP (Address Resolution Protocol)
Definition: A protocol that finds the MAC address of a device when you know its IP address Real-world analogy: Like using a phone book to find someone's street address when you know their name Example: When your computer wants to send data to 192.168.1.100, ARP finds the MAC address of that device Related terms: IP Address, MAC Address, Layer 2
B
Bandwidth
Definition: The amount of data that can be transmitted over a network connection in a given time Real-world analogy: Like the width of a highway - wider highways can handle more cars at once Example: A 100 Mbps internet connection can transfer 100 megabits of data per second Related terms: Speed, Throughput, Latency
Bridge
Definition: A network device that connects two separate network segments and forwards traffic between them Real-world analogy: Like a physical bridge that connects two sides of a river Example: Connecting a wired network segment to a wireless network segment Related terms: Switch, Router, Network Segment
Broadcast
Definition: Sending data to all devices on a network at the same time Real-world analogy: Like making an announcement over a public address system that everyone can hear Example: When a computer asks "Who has IP address 192.168.1.1?" it broadcasts this question to everyone Related terms: Unicast, Multicast, Collision Domain
C
Cat5e / Cat6 Cable
Definition: Types of ethernet cables used to connect network devices Real-world analogy: Like different grades of roads - Cat5e is city streets, Cat6 is highways Example: Using Cat6 cable to connect a server to a switch for faster, more reliable performance Related terms: Ethernet, UTP, Twisted Pair
CIDR (Classless Inter-Domain Routing)
Definition: A method of allocating IP addresses and routing that uses slash notation (like /24) Real-world analogy: Like postal codes that group addresses by area Example: 192.168.1.0/24 means the first 24 bits identify the network, last 8 bits identify individual devices Related terms: Subnet Mask, IP Address, Routing
Client
Definition: A device that requests services from a server Real-world analogy: Like a customer in a restaurant who orders food from the kitchen Example: Your laptop is a client when it requests a webpage from a web server Related terms: Server, Client-Server Model, Workstation
Collision Domain
Definition: A network segment where data collisions can occur when multiple devices transmit simultaneously Real-world analogy: Like a conference call where everyone talks at once and nobody can understand anything Example: In older hub-based networks, all connected devices shared one collision domain Related terms: Switch, Hub, Ethernet
D
Default Gateway
Definition: The router that connects your local network to other networks (usually the internet) Real-world analogy: Like the main exit from your neighborhood that leads to the highway system Example: Your computer uses the default gateway (usually 192.168.1.1) to reach websites on the internet Related terms: Router, IP Address, Routing
DHCP (Dynamic Host Configuration Protocol)
Definition: A service that automatically assigns IP addresses to devices on a network Real-world analogy: Like hotel reception that automatically assigns room numbers to guests when they check in Example: When you connect your laptop to office WiFi, DHCP gives it an IP address automatically Related terms: IP Address, Static IP, Lease
DNS (Domain Name System)
Definition: The system that translates website names into IP addresses Real-world analogy: Like a phone book that converts names into phone numbers Example: DNS translates "google.com" into the IP address 172.217.164.110 Related terms: IP Address, Domain Name, Name Resolution
Duplex
Definition: The ability of a network connection to send and receive data simultaneously Real-world analogy: Full-duplex is like a two-way street; half-duplex is like a one-lane bridge with traffic lights Example: Modern ethernet connections are full-duplex, meaning they can send and receive at the same time Related terms: Half-Duplex, Full-Duplex, Ethernet
E
Ethernet
Definition: The most common wired networking technology using cables and connectors Real-world analogy: Like the standard electrical outlets in your home - everyone uses the same type Example: Connecting your computer to a switch using an ethernet cable Related terms: Cat5e, Cat6, RJ45, Switch
F
Fiber Optic
Definition: Cables that use light to transmit data over long distances at high speeds Real-world analogy: Like using laser pointers instead of shouting to communicate across a stadium Example: Internet service providers use fiber optic cables to connect buildings to their network Related terms: Bandwidth, Single-mode, Multi-mode
Firewall
Definition: A security system that controls what traffic can enter or leave a network Real-world analogy: Like a security guard at a building entrance who checks IDs and visitor passes Example: A firewall blocks hackers from accessing your internal servers from the internet Related terms: Security, Access Control, Router
Frame
Definition: A unit of data transmitted at the data link layer (Layer 2) Real-world analogy: Like an envelope that contains a letter, with addresses written on the outside Example: Ethernet frames contain the data being sent plus MAC addresses of sender and receiver Related terms: Packet, Layer 2, Ethernet
G
Gateway
Definition: A device that connects networks using different protocols or technologies Real-world analogy: Like a translator at the United Nations who converts between different languages Example: A router acting as a gateway between your local network and the internet Related terms: Router, Default Gateway, Protocol
H
Hub
Definition: An older network device that connects multiple devices but creates a single collision domain Real-world analogy: Like a party line telephone where everyone shares the same conversation Example: Hubs have been largely replaced by switches because they cause network collisions Related terms: Switch, Collision Domain, Ethernet
I
ICMP (Internet Control Message Protocol)
Definition: A protocol used for network diagnostics and error reporting Real-world analogy: Like the delivery confirmation receipts that postal services send back Example: The ping command uses ICMP to test if a device is reachable Related terms: Ping, Traceroute, Network Testing
IP Address
Definition: A unique numerical identifier assigned to every device on a network Real-world analogy: Like a postal address for your house that mail carriers use to deliver packages Example: Your computer might have IP address 192.168.1.105 on your office network Related terms: IPv4, IPv6, Public IP, Private IP
ISP (Internet Service Provider)
Definition: A company that provides internet access to homes and businesses Real-world analogy: Like a utility company that provides electricity or water to your building Example: Airtel, Jio, and BSNL are ISPs that provide internet service in India Related terms: Bandwidth, Modem, WAN
L
LAN (Local Area Network)
Definition: A network that covers a small area like an office, home, or building Real-world analogy: Like the internal phone system in one office building Example: Your office network connecting all computers, printers, and phones in the building Related terms: WAN, Network, Ethernet
Latency
Definition: The time delay between sending data and receiving a response Real-world analogy: Like the delay between asking a question and getting an answer Example: High latency makes video calls choppy because there's a delay in voice transmission Related terms: Ping, Round-trip Time, Performance
M
MAC Address
Definition: A unique hardware identifier assigned to every network interface Real-world analogy: Like a serial number permanently printed on a device Example: Every network card has a MAC address like 00:1A:2B:3C:4D:5E Related terms: Physical Address, Layer 2, Ethernet
Modem
Definition: A device that converts digital computer data into signals for transmission over phone or cable lines Real-world analogy: Like a translator that converts English into French so people can communicate Example: Cable modem converts your computer's digital data into signals that travel over coaxial cable Related terms: ISP, Router, WAN
N
NAT (Network Address Translation)
Definition: Technology that allows multiple devices to share a single public IP address Real-world analogy: Like a receptionist who receives calls for a company and transfers them to the right person Example: Your router uses NAT so all office computers can access the internet using one public IP Related terms: Private IP, Public IP, Router
Network Mask
Definition: A number that defines which part of an IP address identifies the network vs. individual devices Real-world analogy: Like area codes in phone numbers that identify which city a number belongs to Example: Subnet mask 255.255.255.0 means the first three numbers identify the network Related terms: Subnet, CIDR, IP Address
O
OSI Model
Definition: A seven-layer model that describes how network communication works Real-world analogy: Like floors in a building - you must go through each floor to reach the top Example: Troubleshooting starts at Layer 1 (physical) and works up to Layer 7 (application) Related terms: Layers, Protocol Stack, Troubleshooting
P
Packet
Definition: A unit of data transmitted across a network, containing both data and addressing information Real-world analogy: Like a package in the mail system with both contents and delivery addresses Example: When you send an email, it's broken into multiple packets that travel independently Related terms: Frame, IP Address, Routing
PAN (Personal Area Network)
Definition: A network covering a very small area, typically around one person Real-world analogy: Like your personal workspace with everything within arm's reach Example: Connecting your phone to Bluetooth headphones creates a PAN Related terms: Bluetooth, WiFi Direct, Personal Device
Ping
Definition: A network tool that tests connectivity by sending a message and waiting for a reply Real-world analogy: Like calling someone on the phone just to see if they answer Example: Running "ping google.com" tests if you can reach Google's servers Related terms: ICMP, Connectivity Testing, Latency
PoE (Power over Ethernet)
Definition: Technology that sends electrical power through ethernet cables along with data Real-world analogy: Like having both water and electricity come through the same pipe Example: IP phones and security cameras often get power through their ethernet connections Related terms: Ethernet, Power Injector, Switch
Port (Network)
Definition: A logical connection point for specific types of network communication Real-world analogy: Like numbered doors in a large office building - each door leads to a different department Example: Web traffic uses port 80, secure web uses port 443, email uses port 25 Related terms: Protocol, Service, Firewall
Protocol
Definition: A set of rules that defines how devices communicate over a network Real-world analogy: Like the rules of grammar that everyone must follow to communicate clearly Example: HTTP is the protocol used for web browsing, SMTP is used for email Related terms: Standard, Communication, Layer
Q
QoS (Quality of Service)
Definition: Network technology that prioritizes certain types of traffic over others Real-world analogy: Like express lanes on highways that allow emergency vehicles to go first Example: QoS ensures VoIP calls get priority over file downloads to maintain call quality Related terms: Bandwidth, Priority, Traffic Management
R
RJ45
Definition: The standard connector type used for ethernet cables Real-world analogy: Like the standard electrical plug shape that fits into wall outlets Example: The connector on the end of your ethernet cable that plugs into your computer Related terms: Ethernet, Cat5e, Cat6, Connector
Router
Definition: A network device that forwards traffic between different networks Real-world analogy: Like a postal sorting facility that determines the best route for packages Example: Your office router connects your internal network to the internet Related terms: Gateway, Routing, WAN, LAN
Routing
Definition: The process of determining the best path for data to travel across networks Real-world analogy: Like using GPS to find the best route from one city to another Example: Internet routers automatically find the fastest path for your data to reach its destination Related terms: Router, Gateway, Path Selection
S
Server
Definition: A computer that provides services to other computers (clients) on a network Real-world analogy: Like a restaurant kitchen that prepares food for customers in the dining room Example: A file server stores and shares documents for everyone in the office Related terms: Client, Service, Network Resource
SSID (Service Set Identifier)
Definition: The name of a WiFi network that appears when you scan for available networks Real-world analogy: Like the name sign on a store that tells you what business it is Example: Your office WiFi might have SSID "CompanyName-WiFi" Related terms: WiFi, Access Point, Wireless Network
Static IP
Definition: An IP address that is manually assigned and never changes Real-world analogy: Like having a reserved parking space with your name on it Example: Servers usually have static IP addresses so other devices can always find them Related terms: DHCP, Dynamic IP, IP Address
Subnet
Definition: A smaller network within a larger network, created by dividing IP address ranges Real-world analogy: Like different departments within a large company building Example: Creating separate subnets for guests, employees, and servers Related terms: VLAN, Network Segmentation, Subnet Mask
Switch
Definition: A network device that connects multiple devices and intelligently forwards traffic between them Real-world analogy: Like an intelligent traffic intersection that directs each car to its specific destination Example: A 24-port switch connects 24 computers and only sends data to the intended recipient Related terms: Hub, Port, MAC Address, Layer 2
T
TCP/IP
Definition: The fundamental suite of protocols that enables internet communication Real-world analogy: Like the postal system's standard procedures for addressing and delivering mail worldwide Example: Every device on the internet uses TCP/IP to communicate with other devices Related terms: Protocol Suite, Internet, Packet
Throughput
Definition: The actual amount of data successfully transmitted over a network in a given time Real-world analogy: Like measuring how many cars actually make it through a busy intersection per hour Example: Your internet plan might advertise 100 Mbps but actual throughput could be 85 Mbps Related terms: Bandwidth, Performance, Speed
Topology
Definition: The physical or logical arrangement of devices in a network Real-world analogy: Like a map showing how roads connect different cities Example: Star topology has all devices connected to a central switch Related terms: Network Design, Physical Layout, Logical Structure
U
UTP (Unshielded Twisted Pair)
Definition: The type of cable used in most ethernet networks, with pairs of wires twisted together Real-world analogy: Like braiding hair - twisting reduces interference from other electrical signals Example: Cat5e and Cat6 cables are both types of UTP cable Related terms: Ethernet Cable, Cat5e, Cat6
Uplink
Definition: A connection from a smaller network device to a larger or higher-level device Real-world analogy: Like a local road that connects to a main highway Example: The uplink port on a switch connects to the router or another switch Related terms: Downstream, Trunk, Connection
V
VLAN (Virtual Local Area Network)
Definition: A way to create separate logical networks on the same physical network equipment Real-world analogy: Like having separate apartment buildings on the same street - same infrastructure, different communities Example: Creating separate VLANs for employees, guests, and security cameras Related terms: Network Segmentation, Switch, Logical Network
VPN (Virtual Private Network)
Definition: A secure connection that extends a private network across a public network like the internet Real-world analogy: Like a secure tunnel that protects travelers from highway robbers Example: Employees working from home use VPN to securely access office systems Related terms: Encryption, Remote Access, Security
W
WAN (Wide Area Network)
Definition: A network that covers a large geographical area, connecting multiple LANs Real-world analogy: Like the highway system that connects different cities Example: A company with offices in multiple cities connected by WAN links Related terms: LAN, Internet, ISP
WiFi
Definition: Wireless networking technology that allows devices to connect without cables Real-world analogy: Like a radio station that broadcasts in all directions for anyone with a receiver Example: Your laptop connecting to the office wireless network Related terms: Wireless, Access Point, SSID, Radio Frequency
Common Acronyms Quick Reference
| Acronym | Full Name | Simple Definition |
|---|---|---|
| AP | Access Point | WiFi transmitter device |
| DHCP | Dynamic Host Configuration Protocol | Automatic IP address assignment |
| DNS | Domain Name System | Converts website names to IP addresses |
| HTTP | HyperText Transfer Protocol | Web browsing standard |
| HTTPS | HTTP Secure | Secure web browsing |
| ICMP | Internet Control Message Protocol | Network testing and error messages |
| IP | Internet Protocol | Network addressing standard |
| ISP | Internet Service Provider | Company that provides internet access |
| LAN | Local Area Network | Network in one building/area |
| MAC | Media Access Control | Hardware address of network devices |
| NAT | Network Address Translation | Shares one public IP among many devices |
| OSI | Open Systems Interconnection | 7-layer network communication model |
| PAN | Personal Area Network | Network around one person |
| PoE | Power over Ethernet | Power delivered through network cables |
| QoS | Quality of Service | Network traffic prioritization |
| SSID | Service Set Identifier | WiFi network name |
| TCP | Transmission Control Protocol | Reliable data delivery standard |
| UDP | User Datagram Protocol | Fast data delivery (less reliable) |
| UTP | Unshielded Twisted Pair | Common ethernet cable type |
| VLAN | Virtual LAN | Logical network separation |
| VPN | Virtual Private Network | Secure connection over internet |
| WAN | Wide Area Network | Network covering large geographical area |
Study Tips for Vocabulary
Memory Techniques
- Use the analogies: The real-world comparisons help connect technical concepts to familiar experiences
- Group related terms: Study switches, hubs, and routers together since they're all network devices
- Practice with scenarios: Use the terms in context - "The DHCP server assigns IP addresses to clients"
- Create your own examples: Think of how you encounter these concepts in your daily work
Common Confusions to Avoid
- Router vs Switch: Router connects different networks; switch connects devices in same network
- Hub vs Switch: Hub shares bandwidth among all devices; switch gives each device dedicated bandwidth
- IP Address vs MAC Address: IP is logical and can change; MAC is physical and permanent
- Bandwidth vs Throughput: Bandwidth is maximum possible; throughput is actual performance
- LAN vs WAN: LAN is local (one building); WAN covers large geographical areas
Practice Activities
- Vocabulary matching: Match terms with definitions without looking at answers
- Scenario identification: Read network problems and identify which terms apply
- Explain to others: Try teaching these concepts to someone else using the analogies
- Create concept maps: Draw connections between related terms to show relationships