NETAD MIDTERMS

Computer Networks

group of interconnected devices.

Nodes

The endpoints or devices connected to the network.

Transmission Media

The physical or logical connections that enable data transmission between nodes.

Protocols

Standardized rules ensuring devices from different manufacturers can communicate properly.

Network Devices

These devices manage data traffic, direct packets to their destinations, and ensure efficient communicati on within the network.

Router

Connects different networks and directs data packets between them using IP addresses

Switch

Manages data traffic by directing data only to the specific device that it is intended for, improving efficiency and reducing network congestion.

Hub

An older, basic device that broadcasts incoming data to all connected devices.

Access Point

Extends a wired network by providing wireless connectivity, commonly used in offices and public spaces.

Local Area Network

Connects devices within a small area.

Wide Area Network

Connects networks across large distances

Metropolitan Area Network

A computer network that connects computers within a metropolitan area, which could be a single large city, multiple cities and towns, or any given large area with multiple buildings.

Personal Area Network

The smallest network type, covering only a few meters around an individual.

Bus Topology

All devices are connected to a single central cable

Star Topology

All devices connect to a central hub or switch

Ring Topology

Each device is connected to exactly two other devices, forming a circular loop.

Mesh Topology

Every device is connected to every other device

TCP

provides reliable, connection-oriented communication between devices on a network.

TCP

It ensures that data packets are delivered in the correct order and without errors, establishing a reliable data transfer mechanism.

IP

t provides a unique identity to each node on the computer network known as an IP address.

HYPERTEXT TRANSFER PROTOCOL

The protocol allows web servers to send files to web browsers to display them for users

FILE TRANSFER PROTOCOL

a client-server protocol that transfers files between a client and a server and operates over TCP/IP.

DOMAIN NAME SYSTEM

an application layer protocol that acts as the internet's phone directory.

DYNAMIC HOST CONFIGURATION PROTOCOL

automates the process of assigning IP addresses to network endpoints so they can communicate with other network devices over IP.

ping

Tests connectivity between devices

ipconfig

Displays IP configuration including: IP address, Subnet mask, and default gateway

tracert

Shows the route packets take across networks.

netstat

View Active Network Connections.

end devices

Devices that send/receive data

Medium

The path data travels through

Network Devices

Devices that direct data

Message

The actual data being sent

Rules (Protocols)

Standards for communication

PCs and End Devices

Send and receive data

Network Interface Card

Connects PC to network (has MAC address)

Network Media (Cable)

Carries signals between devices

Connectors

Plug into ports to make connections

Switch

Connects devices within a LAN; smart traffic cop

Router

Connects multiple networks; routes between them

Switches

Foundation of most business networks — connects computers, printers, servers

Routers

Connect MULTIPLE networks together •Also connect devices to the Internet

Acces Point

Allow devices to connect wirelessly — no cables needed. Acts like an amplifier for your network — extends router's bandwidth

File Sharing

Share documents between computers without USB drives

Resource Sharing

Share printers, scanners, internet connection

Program Sharing

Run software stored on a server

Network Administrator

configures, maintains, and monitors network infrastructure

Personal Area Network

~10 meters (1 person)

Local Area Network

One building / campus

Storage Area Network

Specialized storage network

Twisted Pair (UTP)

Up to 1 Gbps Up to 100 m Least expensive ✓ Indoor LANs, everyday use

Coaxial

10–100 Mbps, Up to 500 m, Inexpensive, Older networks, cable TV

Fiber Optic

Up to 10 Gbps+, Up to 60 km , Most expensive WAN, long-distance, highspeed

WIreless LAN

Up to 54 Mbps Up to 100 m Moderate Wireless mobile devices

media access control address

the hardware address of a NIC

MAC Address

Device hardware (NIC) — physical address

IP Address

Device on a network — logical address

LAN

Also called a 'broadcast domain'

WAN

A 'network of networks' — the Internet is the world's largest WAN • Uses routers to connect different LANs

TCP / IP

a suite of communication protocols that forms the foundation of the Internet and most modern networks.

Transmission COntrol Protocol

Organizes data for SECURE transmission; establishes connection between server and client; ensures data arrives correctly

Internet Protocol

Defines how computers send PACKETS of data; routes packets from origin to destination

Application, Transport, Internet, Network Interface

TCP / IP 4 LAYER

Application

Allows access to network resources (email, web, file transfer)

Transport

Reliable process-to-process delivery; error handling (TCP, UDP)

Internet

Moves packets from source to destination; provides internetworking

Network Interface

Transmission between two devices on the same network

Application, Presentation, Session, transport, Network, data link, physical

OSI MODEL

Application

Human-computer interaction; apps access network services

Presentation

Ensures data is in usable format; handles encryption

Session

Maintains connections; controls ports and sessions

Transport

Transmits data using TCP and UDP protocols

Network

Decides the physical path data will take (routing)

Data link

Defines the format of data on the network (MAC addresses)

Physical

Transmits raw bit stream over the physical medium (cables)

thinnet and thicknet

two types of coaxial

Coaxial

Inner copper wire + insulation + braided shield

Twisted Pair

Most popular worldwide.

FIber Optic

Glass strands + light pulses (no electricity)

single-mode and multimode

two types of fiber optic

USB

Twisted pair wiring inside. PC to peripheral (keyboard, mouse). Can connect to Ethernet via dongle.

Crossover

Connects SAME type devices (PC to PC, switch to switch).

CAT1

Old telephone cable

CAT3

10BASE-T Ethernet

CAT5

fast ethernet

CAT5e

Most popular — Gigabit Ethernet ✓

CAT6

10G Ethernet

CAT7

10G Ethernet (100m at 10G)

UTP-CAT5e

the most popular UTP cable — it replaced coaxial cable for modern networks.

Registered Jack (RJ45)

Standard connector

Plug

The male end on a patch cord

Jack

The receptacle on the wall outlet

PAtch Cable

Short cable used for device-to-device short connections (e.g., PC to nearby switc

Peer to Peer

All computers are equal; share resources with each other

Peer to Peer

Decentralized — no central server

Client/Server

Server centralizes functions; clients access server resources