NETWORK HARDWARE

ISP= Internet Service Provider

• In order to create a network, you need an ISP.
• This company gives you the services that allow you to receive the internet signals that you need.
• Your house receives the signals through the Cable underneath your house.
• When you have your ISP underneath your house, there are different main lines. 
• The mainline comes through your house as an optic cable- through the modem, and the modem converts analog signals to internet signals.
• The modem will connect to one of the ports on the hub. 
• The network cannot handle it when there are too many devices connected to it.

What’s the difference between a Hub and a Switch?

•  A hub sends signals to the entire network node.
•  A switch, on the other hand, routes your message directly to the specific node required.

Packet Transmission

• Data is broken down into smaller pieces called packets.
• A frame consists of these individual packets put together.

Packet Structure

• Each packet is divided into three parts: the packet header, the payload, and the trailer.
• The header stores the protocol version, packet number, destination IP address, and a return-to-sender (RTS) indicator, ensuring there’s a sender address.
• The payload is the actual data you’re sending.
• The trailer includes error correction methods such as parity check, echo, check digit, and checksum.
• Metadata refers to data about the data.

Network Infrastructure

The mainline is a cable typically running underneath the house.

The modem connects to this mainline and to a hub via an Ethernet cable.

This modem is located inside the network box.

The mainline typically enters the house as an optic cable.

Functions of a Router

• A router directs data to specific destinations within a network.
• It has the capability to assign IP addresses.
• Routers can connect a local network to the internet.

Router and Modem

The router receives the signal from the ISP, which is converted into internet signals by the modem. The router then distributes these signals.

Network Terminology

• Node: A device that is part of a network.
• Frame: A large package that consists of smaller units called packets.
• Packets: The basic units that make up a frame.

Packet Structure

Packet Header: Contains the protocol version, packet number, destination IP address, and source address.

Payload: The actual data intended for transmission.

Trailer: Includes error correction methods such as a check digit, checksum, and parity check.

Network Security

• A switch is considered to be more secure than a hub in a network environment.