AP CSP Unit 4: The Infrastructure of the Internet & Computing Systems

Internet

A network of networks linking billions of devices globally; decentralized, open, and scalable.

Decentralized

A structure without a single control point; if one part fails, the rest continues to function.

Open Standards

Protocols that are publicly available and non-proprietary, allowing devices from different manufacturers to communicate.

IETF

Internet Engineering Task Force; an organization that develops and promotes voluntary Internet standards and protocols.

Protocol

A set of rules defining how data is formatted and processed, enabling communication between computers.

Application Layer

The layer where the user interacts with protocols like HTTP and DNS.

Transport Layer

The layer that breaks down and reassembles data using protocols like TCP and UDP.

Internet Layer

The layer responsible for routing data across networks via IP.

Network Interface/Physical Layer

The physical hardware that connects devices, such as fiber optics, copper wires, and Wi-Fi.

IP Address

A unique address assigned to each device on the internet, allowing for data transmission.

IPv4

Internet Protocol version 4, using 32 bits for addressing with a limit of approximately 4 billion unique addresses.

IPv6

Internet Protocol version 6, using 128 bits for addressing, allowing for vastly more addresses than IPv4.

Router

A device that routes information between networks based on the best available path.

Dynamic Routing

A routing method where routers determine paths based on current network conditions rather than a fixed map.

Packet

A small chunk of data broken down for transmission over the internet.

Metadata

Data included in each packet, such as source IP, destination IP, and sequence number.

TCP

Transmission Control Protocol; a reliable protocol ensuring packet delivery through acknowledgments.

UDP

User Datagram Protocol; an unreliable protocol that sends packets without confirmation.

Domain Name System (DNS)

The system that translates human-readable domain names into IP addresses.

DNS Resolver

A server that queries IP addresses for human-readable domain names.

HTTP

HyperText Transfer Protocol; a protocol for transmitting web pages.

HTTPS

HTTP Secure; an encrypted version of HTTP using SSL/TLS for secure communication.

Reliability

The ability of internet systems to function consistently without failure.

Redundancy

Having extra components that serve as backups in case of failure.

Fault Tolerance

The ability of a system to continue operating properly in the event of component failures.

Scalability

The capacity for a system to grow and manage increased demand.

Sequential Computing

A computing model where instructions are executed one after the other.

Parallel Computing

Breaking a program into smaller operations run simultaneously on multiple processors.

Speedup Formula

A calculation to determine the efficiency of parallel solutions; Speedup = Time(sequential) / Time(parallel).

Distributed Computing

Multiple networked devices coordinating actions to solve problems too large for a single computer.

DDoS

Distributed Denial of Service; an attack where many computers flood a server with requests.

Digital Divide

The gap in access to computing devices and the internet based on socioeconomic and demographic factors.

Latency

The time delay between data transmission and receipt; affects perceived speed.

Bandwidth

The maximum data transfer capacity of a network; how much data can flow at once.

Traffic

The volume of data moving across a network at any given time.

Root Server

The top-level DNS server that helps resolve a domain name into an IP address.

Top Level Domain (TLD) Server

Servers responsible for handling specific domain extensions like .com or .org.

Client-Server Model

A model where a client makes requests to a server that processes them and sends back responses.

Mesh of Connections

The interconnected structure of routers and connections that supports the internet's redundancy.

Networked System

A system where multiple devices communicate over a network to enhance processing capacity.

Compression

Reducing data size for faster transmission across networks.

Encryption

The process of converting data into a secure format to prevent unauthorized access.

Latency vs Bandwidth

Confusing latency (delay time) with bandwidth (data capacity); they describe different network characteristics.

Acknowledgment (ACK)

A confirmation sent by TCP to indicate successful receipt of data.

Call and Response Protocol

A communication model where one entity requests information (GET) and another responds.

Peer-to-Peer Network

A decentralized network where each device can act as a client and a server.

Hot Potato Routing

A routing strategy where packets are passed to the next router based on estimated proximity to the destination.