Chapter 5: Computer Networks & The Internet
BASIC TERMS
Computer network: a group of two or more computers or devices that are connected together
and can share information and resources
LAN: connects a variety of devices to a single site (ie. a school printer connected to all school
computers)
WAN: (wide area network) being able to connect remotely, businesses can share resources
with computers at different locations (like a Starbucks connecting their POS systems across
stores)
PAN: (personal area network) is a network that ranges about 10 meters. Most common
example of a PAN is your airpods connection to your phone
An internet: a network is connected with many other networks
The Internet: the world’s largest and most familiar Internet
ISP: Internet Service Provider, has 3 functions that it provides for internet access
IP: (Internet Protocol) specific software used by the Internet to communicate. An IP address is a
number assigned to all connection devices
DNS: Domain Name System. Translates the numbers in IP addresses (IPv4 or IPv6 format) into
recognizable words
TCP: Transmission Control Protocol. How software apps can communicate across networks
and how data packets are assembled/reassembled when they reach their destination
TCP/IP: Transmission Control Protocol/Internet Protocol. The interaction of how TCP (how
software apps communicate across networks) and IP (how to address and route data packets)
interact to connect devices to the Internet
Internet of Things (IoT): combines connected devices with automated systems that gather
data, analyze it, and then convert it into usable information
Networks and the Internet
➔ Networks range in size, from small home networks to the Internet (the world's LARGEST
internet)
- Computer Networks support different types of software applications and services like:
- World Wide Web
- Digital video and audio
- Storage
- Application servers
- Email, and much more
➔ When Networks link together, it creates an internet
- The Internet (with a capital “I” refers to the most familiar and largest internet
- Allows communication/exchange of information and data
LANs and WANs
➔ A Local Area Network (LAN) connects devices at a single site, like an office or retail
store
- Connects devices within a limited geographical range (usually no more than half a mile)
and are all located in a spot controlled by the organization that owns the LAN
- Devices that are in a LAN can be connected with wires or be wireless (ie. Ethernet
cables, Bluetooth, WiFi)
, - Institute of Electrical and Electronics Engineers (IEEE) creates and publishes rules for
LANs, which are called IEEE 802. Every LAN protocol begins with the number 802
- IEEE 802.3 protocol- covers wired LAN connections (which are also called
Ethernet)
- Specifies the hardware characteristics, like which wire carries which signal, and
how messages are packaged and processed for transmission over a LAN
★ Connecting a LAN to the Internet
- You first need a connection to the Internet , provided by an internet service provider
(ISP)
- ISPs provide 3 functions
1. Provides an IP (internet protocol) address
2. Provides a gateway or access to the resource on the Internet, which also
receives the data on your computer and sends it to the Internet
3. The ISP pays for access to the Internet
a. ISPs charge a fee for customers for this access, and part of it goes to the
Internet
- In addition to the ISP, you also need a way to connect to the Internet (usually wired or
wireless LANs
- Wired LANs connect by fiber optic cables or Ethernet cables
- Wireless LANs use access points to convert wired LANs to wireless
- Can also use digital subscriber lines (DSL)- basically telephone lines, and cable
via coaxial (thick cables that can go long destinations)
➔ A Wide Area Network (WAN) connects many devices between two or more geographical
locations
- WANs support communications and sharing of information between devices across
cities, countries, and the globe
- WANs are usually used by large organizations that need to transmit data and information
across many locations
- For an organization to set up a WAN, they must use a WAN vendor (ie.Cisco Systems,
VMware)
- These vendors setup the WAN and provide software for the organization to use
How the Internet Works
- The Internet is made up of complex hardware connected by large fiber optic cable
bundles called the Internet backbone, along with specific software called the suite of
Internet protocols
- Each network that connects to the Internet uses its own “communication media” like a
fiber optic cable, television (coax) cable, telephone lines (DSL), cellular signals or
satellite (microwave) signals
- The connection points in the Internet are called nodes
★ When data is stored on the Internet, they are on specialized computers called servers
★ Data is transferred from one network to another through hardware called routers
★ Information sent over the Internet is transferred in small groups called packets
➔ A router sends each packet to the correct receiving router to the fastest route possible
, EXAMPLE: UPS- Sending packets through the Internet is like our UPS mailing system!
Sending a Package or Packet UPS Internet
1. Package assembly Package is readied for The data packet is
shipping assembled
2. Put a name on the Business or person’s name is Correct domain name is
package identified identified (ie. amazon.com)
This domain name is affiliated
with an IP address
3. Find the address Search for organization’s or Look up the IP address. The
individual’s phone number domain name system (DNS)
(information may have been is used to simplify the
provided process
4. Address the package Receiver's mailing address is IP address is added to the
added to the package packet
5. Create a shipping Shipping label with fees is Transmission Control
label created and attached to the Protocol (TCP) is an Internet
package protocol that ensures delivery
of packets
6. Ship the package Ship the package via air or Message is sent (shipped)
ground shipping! using a variety of different
carrieres (ISPs)
Components of an IP Address
- An IP address is a number that is assigned to all information technology connection
devices (routers, modems- device that connects your LAN to the WAN, etc) that
identifies the device to others and allows it to communication with other devices on a
computer network, including the Internet
- An IP address is like your home address; when you order a package you provide your
mailing address (your IP address) in your town/city (network)
- An IP address is needed to receive information- how can you receive mail without an
address?
- Static addresses are permanently assigned IP addresses, and used for email
servers, businesses, permanent home addresses, etc
- Dynamic addresses come from a pool of available IP addresses assigned to
your ISP each time you connect to the Internet
- IP addresses have many different formats;
- IPv4 addresses have a four-decimal notation, like (182.124.7.9), and allows for
about 4 billion IPv4 addresses
- IPv6 addresses are now being used due to the demand of IP addresses
- Format is (2001:0db8:85a3:0000:0000:8a2e:0370:7334) and can made
up at least 340 undecillion IP addresses (which is hella)
BASIC TERMS
Computer network: a group of two or more computers or devices that are connected together
and can share information and resources
LAN: connects a variety of devices to a single site (ie. a school printer connected to all school
computers)
WAN: (wide area network) being able to connect remotely, businesses can share resources
with computers at different locations (like a Starbucks connecting their POS systems across
stores)
PAN: (personal area network) is a network that ranges about 10 meters. Most common
example of a PAN is your airpods connection to your phone
An internet: a network is connected with many other networks
The Internet: the world’s largest and most familiar Internet
ISP: Internet Service Provider, has 3 functions that it provides for internet access
IP: (Internet Protocol) specific software used by the Internet to communicate. An IP address is a
number assigned to all connection devices
DNS: Domain Name System. Translates the numbers in IP addresses (IPv4 or IPv6 format) into
recognizable words
TCP: Transmission Control Protocol. How software apps can communicate across networks
and how data packets are assembled/reassembled when they reach their destination
TCP/IP: Transmission Control Protocol/Internet Protocol. The interaction of how TCP (how
software apps communicate across networks) and IP (how to address and route data packets)
interact to connect devices to the Internet
Internet of Things (IoT): combines connected devices with automated systems that gather
data, analyze it, and then convert it into usable information
Networks and the Internet
➔ Networks range in size, from small home networks to the Internet (the world's LARGEST
internet)
- Computer Networks support different types of software applications and services like:
- World Wide Web
- Digital video and audio
- Storage
- Application servers
- Email, and much more
➔ When Networks link together, it creates an internet
- The Internet (with a capital “I” refers to the most familiar and largest internet
- Allows communication/exchange of information and data
LANs and WANs
➔ A Local Area Network (LAN) connects devices at a single site, like an office or retail
store
- Connects devices within a limited geographical range (usually no more than half a mile)
and are all located in a spot controlled by the organization that owns the LAN
- Devices that are in a LAN can be connected with wires or be wireless (ie. Ethernet
cables, Bluetooth, WiFi)
, - Institute of Electrical and Electronics Engineers (IEEE) creates and publishes rules for
LANs, which are called IEEE 802. Every LAN protocol begins with the number 802
- IEEE 802.3 protocol- covers wired LAN connections (which are also called
Ethernet)
- Specifies the hardware characteristics, like which wire carries which signal, and
how messages are packaged and processed for transmission over a LAN
★ Connecting a LAN to the Internet
- You first need a connection to the Internet , provided by an internet service provider
(ISP)
- ISPs provide 3 functions
1. Provides an IP (internet protocol) address
2. Provides a gateway or access to the resource on the Internet, which also
receives the data on your computer and sends it to the Internet
3. The ISP pays for access to the Internet
a. ISPs charge a fee for customers for this access, and part of it goes to the
Internet
- In addition to the ISP, you also need a way to connect to the Internet (usually wired or
wireless LANs
- Wired LANs connect by fiber optic cables or Ethernet cables
- Wireless LANs use access points to convert wired LANs to wireless
- Can also use digital subscriber lines (DSL)- basically telephone lines, and cable
via coaxial (thick cables that can go long destinations)
➔ A Wide Area Network (WAN) connects many devices between two or more geographical
locations
- WANs support communications and sharing of information between devices across
cities, countries, and the globe
- WANs are usually used by large organizations that need to transmit data and information
across many locations
- For an organization to set up a WAN, they must use a WAN vendor (ie.Cisco Systems,
VMware)
- These vendors setup the WAN and provide software for the organization to use
How the Internet Works
- The Internet is made up of complex hardware connected by large fiber optic cable
bundles called the Internet backbone, along with specific software called the suite of
Internet protocols
- Each network that connects to the Internet uses its own “communication media” like a
fiber optic cable, television (coax) cable, telephone lines (DSL), cellular signals or
satellite (microwave) signals
- The connection points in the Internet are called nodes
★ When data is stored on the Internet, they are on specialized computers called servers
★ Data is transferred from one network to another through hardware called routers
★ Information sent over the Internet is transferred in small groups called packets
➔ A router sends each packet to the correct receiving router to the fastest route possible
, EXAMPLE: UPS- Sending packets through the Internet is like our UPS mailing system!
Sending a Package or Packet UPS Internet
1. Package assembly Package is readied for The data packet is
shipping assembled
2. Put a name on the Business or person’s name is Correct domain name is
package identified identified (ie. amazon.com)
This domain name is affiliated
with an IP address
3. Find the address Search for organization’s or Look up the IP address. The
individual’s phone number domain name system (DNS)
(information may have been is used to simplify the
provided process
4. Address the package Receiver's mailing address is IP address is added to the
added to the package packet
5. Create a shipping Shipping label with fees is Transmission Control
label created and attached to the Protocol (TCP) is an Internet
package protocol that ensures delivery
of packets
6. Ship the package Ship the package via air or Message is sent (shipped)
ground shipping! using a variety of different
carrieres (ISPs)
Components of an IP Address
- An IP address is a number that is assigned to all information technology connection
devices (routers, modems- device that connects your LAN to the WAN, etc) that
identifies the device to others and allows it to communication with other devices on a
computer network, including the Internet
- An IP address is like your home address; when you order a package you provide your
mailing address (your IP address) in your town/city (network)
- An IP address is needed to receive information- how can you receive mail without an
address?
- Static addresses are permanently assigned IP addresses, and used for email
servers, businesses, permanent home addresses, etc
- Dynamic addresses come from a pool of available IP addresses assigned to
your ISP each time you connect to the Internet
- IP addresses have many different formats;
- IPv4 addresses have a four-decimal notation, like (182.124.7.9), and allows for
about 4 billion IPv4 addresses
- IPv6 addresses are now being used due to the demand of IP addresses
- Format is (2001:0db8:85a3:0000:0000:8a2e:0370:7334) and can made
up at least 340 undecillion IP addresses (which is hella)
