Telecommunications, the Internet, and Wireless Technology

Router, Server, Network Interface Card (NIC), Switch, PC

Components of a Simple Computer Network

IP Address

Global network address - identifies the device and its location using the Internet

MAC Address

Local network address - embedded in the hardware to identify the device

The Domain Name System (DNS)

Converts IP addresses to domain names using hierarchal structure

Third-Level Domain (Host), Second-Level Domain, Top-Level Domain, Internet Root Domain

Domain Hierarchy (Ascending)

Examples of Second-Level Domains

Expedia, Google, Congress

Examples of Top-Level Domains

edu, com, gov, org, net

Packet Switching

Method of slicing digital messages into parcels (packets), sending the packets along different communication paths as they become available, and then reassembling packets at destination

Packet-Switched Networks/Packet Communications

Data are grouped in small packets, which are transmitted independently over various communications channels and reassembled at their final destination

Modern

A device that translates digital signals into analog form (and vice versa) so that computers can transmit data over analog networks such as telephone lines and cable networks

Twisted Pair Wire

Strands of copper twisted in pairs for voice and data communications

10-100+ Mbps

Coaxial Cable

Thickly insulated copper wire, which is capable of high-speed data transmission and less subject to interference than twisted wire

Used for cable TV and networks with longer runs (more than 100 meters)

Up to 1 Gbps

Fiber-Optic Cable

Strands of clear glass fiber, transmitting data as pulses of light generated by lasers

Useful for high-speed transmission of large quantities of data, so often used for network backbone

More expensive than other physical transmission media and harder to install

15 Mbps - 6+ Tbps

Wireless Transmission Media

Based on radio signals of various frequencies and includes both terrestrial and satellite microwave systems and cellular networks

Usef for long-distance, wireless communication and internet access

Up to 600+ Mbps

Bps

Bits per second

Megabit (Mbps)

1,000,000 bps

Kilobit (Kbps)

1,000 bps

Gigabit (Gbps)

1B bps

Transmission Control Protocol/Internet Protocol (TCP/IP)

Common worldwide standard that is the basis for Internet

Application Layer, Transport Layer, Internet Layer, Network Interface Layer

Four Layers of TCP/IP

Application Layer - Sender Side

Processes the internet use request from different apps

Transport Layer - Sender Side

Slices messaged into data packets (PPs) following TCP

Internet Layer - Sender Side

Attached IP Address to each PP following IP

Network Interface Layer - Sender Side

Puts PPs onto the transmission medium

Network Interface Layer - Receiver Side

Gets PPs from the Sender Network Interface Layer

Internet Layer - Receiver Side

Check IP Address from each PP

Transport Layer - Receiver Side

Reassemble PPs to form the original message

Application Layer - Receiver Side

Displays messages in the requested apps