Networking

An Access Port connects one device to one VLAN.

Auto-MDIX is a smart feature that automatically fixes cable connection problems so devices can talk without worrying about cable type.

How wide the data pipe is. It tells you the maximum amount of data that can squeeze through the connection at once, not how fast a single piece of data travels.

BGP decides which road packets should take to travel across the internet.

A bit is a single 0 or 1. A byte is a group of 8 bits that together make a piece of data.

The road is closed, but it's ready to open if needed.

Bridge ID is like a switch's ID card that STP uses to decide which switch should lead the network.

CIDR tells how many IP addresses are in a network and which addresses belong to it.

A client is something (like a computer or app) that asks a server for information or services.

It is a LAN cable where the wires are crossed so that two same-type devices can talk directly.

A datagram is data wrapped with UDP information that is sent quickly without setting up a connection.

Decapsulation means unwrapping the received data step by step to get the original message.

The Default VLAN is the starting VLAN that every new switch uses.

A Designated Port is the traffic officer responsible for one network cable.

The Destination MAC Address is the delivery address written on the Ethernet package.

The phonebook of the internet. A service that translates name addresses that humans can easily remember into number coordinates that computers use to find each other.

DTP is like two people agreeing whether to open a multi-lane road before vehicles start using it.

It is a live GPS system for internet traffic that automatically recalculates your route when there is a road closure.

Encapsulation means wrapping data with extra information at each network layer so it can travel properly.

Ethernet is the standard way computers are connected using cables so they can talk to each other.

Ethernet standards are fixed rules that tell how fast a network can run and how far cables can carry data.

Fiber optics is a special cable that sends data using light instead of electricity, making it very fast and suitable for long distances.

Fiber standards are fixed rules that tell how fast fiber internet works and how far data can travel through fiber cables.

A firewall is a security guard for your network that decides which data is allowed in and which is blocked.

It's the waiting time before opening the road.

The road is open and traffic flows normally.

A frame is a packet wrapped with Ethernet information so it can travel inside a local network.

The FCS is the package's quality check that tells the receiver whether the data arrived safely.

Full duplex means both devices can talk and listen at the same time.

It's the Root Bridge saying, "I'm still here."

A hop is one step from one device to another when data is moving through a network.

It tells the network where the packet needs to go.

It tells the network which packets should be handled first and warns when the network is getting busy.

It gives instructions about whether a packet can be split and whether more pieces are on the way.

It tells the receiver where each piece of a split packet fits in the original message.

It checks whether the IPv4 header was damaged while traveling through the network.

It gives a packet a "group number" so its pieces can be put back together correctly.

It tells the receiver where the IP header ends and the actual message begins.

It adds extra instructions to a packet only when they are needed.

It adds empty space so the IP header has the correct size before the actual data begins.

It tells IPv4 which program inside the operating system should receive the packet next.

It tells the receiver who sent the packet.

It gives every packet a limited number of chances to travel through routers before it expires.

It tells the receiver exactly how big the entire IP packet is.

It tells the receiver which "language" the IP packet is written in.

The waiting time or "lag"—how long it takes for a message to travel from your device to the server and back.

A Layer 3 Switch is a switch that can also act like a router, allowing different VLANs to communicate much faster.

The switch learns where everyone is before opening the road.

The switch is thinking before opening the road.

It is the permanent ID card of your network device (like a fingerprint, which never changes).

It's how long a switch waits before saying, "The Root Bridge is probably gone."

A multicast address lets one sender share the same information with only the people who asked to receive it.

The Native VLAN is the "default lane" for traffic that arrives without a VLAN label.

NAT is a translator that lets your private home devices communicate with the public Internet.

A protocol is like a common language that computers use to talk to each other.

A network topology is simply the map showing how all network devices are connected.

They are organizations that make the “rulebook” for how computers and networks should talk to each other.

A packet is a small piece of a large file or message sent over the internet.

A packet is data wrapped with IP information so it can travel across different networks.

Payload is the real data inside a packet/frame after removing extra networking information.

An address extension or "apartment number" on a computer that directs incoming internet traffic to the correct software program.

The Preamble tells the receiver, "Get ready, I'm about to send you an Ethernet frame."

A PDU is just the name of data at each network layer.

RFC is like an official instruction document that tells how internet rules and protocols should work.

RJ-45 is the plug at the end of a LAN cable that you insert into your computer or router.

A Root Port is a switch's favorite road to reach the Root Bridge.

A router is a device that connects different networks and sends data between them.

A segment is data wrapped with TCP information so it can be safely sent to the correct application.

A server is a powerful computer or system that gives information or services to other devices.

A socket is an open, live communication line between two programs.

The Source MAC Address is the return address on the Ethernet package.

Standards are common rules that all network devices follow so they can understand each other.

The SFD says, "Ready? The real Ethernet frame starts now."

It is like writing permanent driving directions on a sticky note and taping it to your router.

STP allows multiple network paths for safety but keeps only one active at a time to prevent data from endlessly circulating.

It is a LAN cable where both ends are wired the same so devices like a PC and switch can connect easily.

A subnet is a small network inside a bigger network.

Subnetting divides one big neighborhood into smaller neighborhoods.

An SVI is the "gateway" of a VLAN inside a Layer 3 switch.

A switch is a device that connects computers in a small/local network and sends data only to the right computer.

The basic rules and structural framework that connect the entire internet, ensuring data gets broken down into packets, labeled with addresses, and put back together in the correct order.

This layer is the “hardware level” that carries data using cables or wireless signals.

This layer helps devices in the same network send data to the correct device using hardware addresses (MAC addresses).

This layer makes sure data can travel from one network to another network using IP addresses.

This layer makes sure data reaches the correct app on the correct device.

This layer is where user apps (like Chrome or email) talk to the network using specific rules.

The actual amount of traffic passing through the pipe. While bandwidth is the limit of what could flow, throughput is how much actually flows.

A Trunk Port is one cable that safely carries traffic for many VLANs at the same time.

TTL is the fuel gauge of a packet. Every router uses a little fuel. When the fuel reaches zero, the packet cannot continue and is thrown away.

Twisted pair cables are network wires twisted together so that data can travel without disturbance from outside signals.

It tells which pins in a LAN cable are used to send data and which are used to receive data.

The Type field is the label that tells the computer what kind of data is inside the Ethernet package.

A VLAN is like creating separate rooms inside one large office building.

VLSM gives every department a room that matches its size instead of giving everyone the same room.

A VPN is a secure middleman that safely forwards your Internet traffic.

VTP is like automatically sharing an updated department list with every office.