TCP/IP Model and Communication Systems Overview

MAC Address

Unique identifier for network interfaces in Ethernet.

Switched Ethernet

Provides dedicated bandwidth, reducing collisions.

Internet Protocol (IP)

Addresses and routes packets across networks.

Transmission Control Protocol (TCP)

Reliable, connection-oriented protocol for data transfer.

Application Layer

Top layer of TCP/IP model; includes HTTP, FTP.

Transport Layer

Handles data transfer; includes TCP, UDP protocols.

Network Layer

Responsible for packet routing; uses IP protocol.

Physical Layer

Transmits raw binary data over physical mediums.

Layer Interaction

Layers provide services to adjacent layers.

Logical Link Control (LLC)

Manages frame synchronization, flow control, error checking.

Media Access Control (MAC)

Manages access to physical transmission medium.

CSMA/CD

Collision detection method for Ethernet networks.

Address Resolution Protocol (ARP)

Translates IP addresses to MAC addresses.

User Datagram Protocol (UDP)

Connectionless protocol, faster but less reliable.

Socket

Endpoint for network communication, defined by IP and port.

Local Domain Name Server (DNS)

Translates domain names to IP addresses.

DNS Cache

Stores resolved domain names for faster access.

Top-Level Domain (TLD)

Highest domain level, e.g., .com, .org.

Country Code Top-Level Domain (ccTLD)

Specific to a country, e.g., .uk for United Kingdom.

Quality of Service (QoS)

Manages network traffic to prioritize critical data.

Firewall

Controls network access and protects against threats.

Communication Channel

Medium for transferring data between devices.

Analog Signaling

Represents information as continuous signals.

Digital Signaling

Represents information as discrete binary values.

Simplex Channel

One-way communication, e.g., radio broadcast.

Half-Duplex Channel

Two-way communication, not simultaneous, e.g., walkie-talkie.

Full-Duplex Channel

Simultaneous two-way communication, e.g., telephone call.

Modulation

Varying a carrier signal to encode data.

Frequency-Division Multiplexing (FDM)

Allocates frequency bands for simultaneous data transmission.

Time-Division Multiplexing (TDM)

Assigns time slots for sequential data transmission.

Fiber-Optic Cable

Offers high bandwidth and low signal loss.

Guided Media

Physical pathways for data, e.g., twisted pair cables.

Unguided Media

Uses air for transmission, e.g., radio waves.

Digital Transmission Preference

Preferred for higher fidelity and noise resistance.

Digital Transmission

Less noise, easier compression, higher speeds, reliable integrity.

Manchester Encoding

Combines data and clock signals to prevent synchronization issues.

Bandwidth

Range of frequencies for data transmission capacity.

Wi-Fi

Long-range technology for high-speed internet connections.

Bluetooth

Short-range technology for connecting peripheral devices.

Frequency-Hopping Spread Spectrum (FHSS)

Rapidly switches frequencies to reduce interference and improve security.

Wavelength-Division Multiplexing (WDM)

Transmits multiple data channels using different light wavelengths.

Repeaters

Amplify signals to extend transmission distance effectively.

Cellular Technology

Used for long-range mobile data communication services.

Distributed System

Network of independent computers appearing as a single system.

Content Delivery Network (CDN)

Example of distributed systems for streaming content delivery.

Client-Server Model

Clients request resources; servers provide and process them.

Web-Based Computing

Access applications via web browsers over the internet.

Peer-to-Peer (P2P) Computing

Decentralized model where peers share equal responsibilities.

Computing Clusters

Interconnected computers working together as a single system.

Storage Area Networks (SANs)

High-speed networks connecting storage devices to servers.

Cloud Computing

Delivers computing resources over the internet on demand.

Infrastructure as a Service (IaaS)

Cloud service providing virtualized computing resources.

Grid Computing

Pooling resources of multiple computers for a single problem.

Supercomputing

Single powerful computer handling intensive computational tasks.

Virtualization

Multiple virtual instances on a single physical machine.

Google's Networked Systems

Distributed servers delivering fast search results globally.

Facebook's Networked Systems

Manages user interactions using a distributed server setup.

Barebones Computer System Limitation

Cannot run multiple programs concurrently.

File system management

The process of managing how data is stored and retrieved on storage devices.

Managing hardware resources

The function of an operating system to allocate and control hardware components.

Processing API calls

The handling of requests made by applications to the operating system for services.

Compiling programs

The process of converting source code into executable code.

Multiprocessing

The ability of an operating system to support multiple processors for executing tasks.

Multiuser multitasking

The capability of an operating system to manage the execution of multiple tasks by multiple users.

Hyper-threading

A technology that allows a single processor to act like multiple processors to improve performance.

Event-driven programming

A programming paradigm in which the flow of the program is determined by events.

Kernel

The core part of the operating system that manages system resources and communication between hardware and software.

File management

The process of organizing and keeping track of files on a storage device.

I/O services

Services provided by the operating system for input and output operations.

Event-driven

Refers to an operating system that reacts to events such as interrupts or service requests rather than executing continuously.

Diskless workstation

A computer that relies on network-based services for storage and operation instead of local disk storage.

User interface

The part of the operating system that allows users to interact with the computer system.

Command Line Interface (CLI)

An interface that allows users to interact with the computer by typing text commands.

Graphical User Interface (GUI)

An interface that allows users to interact with the computer using graphical elements like windows and icons.

Application Programming Interface (API)

A set of routines, protocols, and tools for building software and applications.

Common look and feel

A design principle that ensures consistency in the appearance and behavior of applications.

File management system

The system responsible for interfacing between the logical view of files and their physical storage.

Sequential access

A method of accessing data where records are read in order.

Indexed access

A method that uses an index to locate records for efficient access.

Random access

A method that allows direct retrieval of any record by its location.

Contiguous allocation

A storage allocation method that involves storing a file in consecutive blocks on the disk.

Fragmentation

The condition where storage space is used inefficiently, leading to gaps between allocated memory.

Logical file view

Represents data as understood by users, such as text files or database records.

Physical file view

Describes how data is stored on the device, such as blocks or clusters.

CLI advantages

Provides greater power and flexibility for executing detailed tasks with fewer system resources.

Indexed allocation

Uses pointers to locate blocks of data for efficient random access.