INTERNET
INFRASTRUCTURE
Internet
A
means of connecting a computer to any other computer anywhere in the world via
dedicated routers and servers. When two computers are connected over the
Internet, they can send and receive all kinds of information such as text,
graphics, voice, video, and computer programs.
No
one owns Internet, although several organizations the world over collaborate in
its functioning and development. The high-speed, fiber-optic cables (called
backbones) through which the bulk of the Internet data travels are owned by
telephone companies in their respective countries.
Internet
A Hierarchy of Networks
•
From a single computer to LAN
•
From LAN to ISP
•
ISP to WWW
•
Every
computer that is
connected to the
Internet is part
·
of
a network, even
the one in
your home. For
example,
·
you
may use a
modem and dial
a local number
to
·
connect
to an Internet
Service Provider (ISP).
At work,
·
you
may be part
of a local
area network (LAN),
but you
·
most
likely still connect
to the Internet
using an ISP
that
·
your company has contracted with.
•
When
you connect to
your ISP, you
become part of
their
·
network.
The ISP may
then connect to
a larger network
·
and
become part of
their network. The
Internet is simply
·
a network of networks.
•
Most
large communications companies
have their own
·
dedicated
backbones connecting various
regions. In
·
each
region, the company
has a Point
of Presence
·
(POP).
•
The
POP is a
place for local
users to access
the
·
company's
network, often through
a local phone
number
·
or
dedicated line. The
amazing thing here
is that there
is
·
no
overall controlling network.
Instead, there are
several
·
high-level
networks connecting to
each other through
·
Network Access Points or NAPs.
Internet service provider (ISP)
·
ISP Also called IAP (Internet Access
Provider).
·
Company that provides access to the
internet.
·
Usually
ISP provide software
package, username,
·
password and access phone number and modem
·
ISP
are connected to
one another through
Network
·
Access Points (NAPs)
·
Example of ISP : TM
Internet Protocol
Short for Internet Protocol address, an IP or IP
address is a number (example shown right) used to indicate the
location of a computer or other device on a network using TCP/IP. These addresses
are similar to those of your house; they allow data to reach the appropriate
destination on a network and the Internet.
IPv4 vs.
IPv6
·
As the Internet and technology evolve,
there has been an increasing demand for IP addresses. To help meet the demand
for IP addresses, there are two types of addresses used today, IPv4 and IPv6. Although you may
only deal with an IPv4 address in your local home, school, or small office you
should also be aware of IPv6 addresses for when you encounter them.
·
Example of an IPv4 address:
·
69.72.169.241
·
Example of an IPv4 address:
·
2601:681:4200:c5c0:516:f0bb:ac3b:46bd
IP address
classes
·
With an IPv4 IP address there are five
classes of available IP ranges: Class A, Class B, Class C, Class D and Class E,
while only A, B, and C are commonly used. Each class allows for a range of
valid IP addresses, shown in the following table.
Class
|
Address Range
|
Supports
|
Class A
|
1.0.0.1 to 126.255.255.254
|
Supports 16 million hosts on each of
127 networks.
|
Class B
|
128.1.0.1 to 191.255.255.254
|
Supports 65,000 hosts on each of
16,000 networks.
|
Class C
|
192.0.1.1 to 223.255.254.254
|
Supports 254 hosts on each of 2
million networks.
|
Class D
|
224.0.0.0 to 239.255.255.255
|
Reserved for multicast groups.
|
Class E
|
240.0.0.0 to 254.255.255.254
|
Reserved for future use, or Research
and Development Purposes.
|
·
Ranges 127.x.x.x are reserved for the loopback or
localhost, for example, 127.0.0.1 is the loopback
address. Range 255.255.255.255 broadcasts to
all hosts on the local network.
IP address
breakdown
·
Every IP address is broken down into
four sets of octets and
translated into binary to
represent the actual IP address. The below table is an example of the IP
255.255.255.255. If you are new to binary, we highly recommend reading our binary and hexadecimal conversions section
to get a better understanding of what we're doing in the below charts.
IP:
|
255
|
255
|
255
|
255
|
Binary value:
|
11111111
|
11111111
|
11111111
|
11111111
|
Octet value:
|
8
|
8
|
8
|
8
|
·
For an example, let's break down the IP
"166.70.10.23" in the following table. The first row contains the
separate sections of the IP address, the second has binary values, and the
third row shows how the binary value equals the section of the IP address.
IP:
|
166
|
70
|
10
|
23
|
Binary value:
|
10100110
|
01000110
|
00001010
|
00010111
|
Numerical value:
|
128+32+4+2=166
|
64+4+2=70
|
8+2=10
|
16+4+2+1=23
|
Automatically
assigned addresses
·
There are IP addresses that are
automatically assigned (dynamic
allocation) when you set up a home network. These default addresses
are what allow your computer and other network devices to communicate and
broadcast information over your network. Below are the most commonly assigned
default addresses for home networks.
192.168.1.0
|
0 is the automatically assigned
network address.
|
192.168.1.1
|
1 is the commonly used address used as
the gateway.
|
192.168.1.2
|
2 is also a commonly used address used
for a gateway.
|
192.168.1.3 - 254
|
Addresses beyond 3 are assigned to
computers and devices on the network.
|
192.168.1.255
|
255 is automatically assigned on most
networks as the broadcast address.
|
·
If you have ever connected to your home
network, you should be familiar with the gateway address or 192.168.1.1, which
is the address you use to connect to your home network router to change its
settings. Another common IP range that may be used is 10.0.0.3-254.
Getting an
IP address
·
By default the router you use will
assign each of your computers their own IP address, often using NAT to forward the
data coming from those computers to outside networks such as the Internet. If
you need to register an IP address that can be seen on the Internet, you must
register through InterNIC or
use a web host that can assign you addresses.
·
Anyone who connects to the Internet is
assigned an IP address by their Internet Service Provider (ISP), which has registered
a range of IP addresses. For example, let's assume your ISP is given 100
addresses, 109.145.93.150-250. In this range, the ISP owns addresses
109.145.93.150 to 109.145.93.250 and can assign any address in that range to
its customers. So, all these addresses belong to your ISP until they are assigned
to a customers computer. In the case of a dial-up connection,
you are given a new IP address each time you dial into your ISP. With most broadband Internet
service providers, you are always connected to the Internet your address rarely
changes. It remains the same until the service provider requires otherwise.
Type of Internet Connection
There are many ways a personal electronic device can connect to the
internet. They all use different
hardware and each has a range of connection speeds. As technology changes, faster internet
connections are needed to handle those changes.
I thought it would be interesting to list some of the different types of
internet connections that are available for home and personal use, paired with
their average speeds.
Dial-Up
Dial-up access is cheap but slow. A modem (internal or external) connects
to the Internet after the computer dials a phone number. This analog signal is converted to digital
via the modem and sent over a land-line serviced by a public telephone
network. Telephone lines are variable in
quality and the connection can be poor at times. The lines regularly experience interference
and this affects the speed, anywhere from 28K to 56K. Since a computer or other device shares the
same line as the telephone, they can’t be active at the same time.
DSL
DSL stands for Digital Subscriber Line.
It is an internet connection that is always “on”. This uses 2 lines so your phone is not tied
up when your computer is connected.
There is also no need to dial a phone number to connect. DSL uses a router to transport data and the
range of connection speed, depending on the service offered, is between 128K to
8 Mbps.
Cable
Cable provides an internet connection through a cable modem and operates
over cable TV lines. There are different
speeds depending on if you are uploading data transmissions or
downloading. Since the coax cable
provides a much greater bandwidth over dial-up or DSL telephone lines, you can
get faster access. Cable speeds range
from 512K to 20 Mbps.
Wireless
Wireless, or Wi-Fi, as the name suggests, does not use telephone lines or
cables to connect to the internet.
Instead, it uses radio frequency.
Wireless is also an always on connection and it can be accessed from
just about anywhere. Wireless networks
are growing in coverage areas by the minute so when I mean access from just
about anywhere, I really mean it. Speeds
will vary, and the range is between 5 Mbps to 20 Mbps.
Satellite
Satellite accesses the internet via a satellite in Earth’s orbit. The
enormous distance that a signal travels from earth to satellite and back again,
provides a delayed connection compared to cable and DSL. Satellite connection speeds are around 512K
to 2.0 Mbps.
Cellular
Cellular technology provides wireless Internet access through cell
phones. The speeds vary depending on the
provider, but the most common are 3G and 4G speeds. A 3G is a term that describes a 3rd
generation cellular network obtaining mobile speeds of around 2.0 Mbps. 4G is the fourth generation of cellular
wireless standards. The goal of 4G is to achieve peak mobile speeds of 100 Mbps
but the reality is about 21 Mbps currently.
________________________________________________________________________________
I attended classes and
series this week on the topic this week is the Internet infrastructure. This
topic is quite difficult for me but after I inspect it not so difficult for me.
What is discussed in this topic is the internet protocol. I know the Internet
protocol is used when we do a search, for example IP address, and it's
converted into a binary code. In addition I have also learned about the types
of internet connections such as dial connection and access, cable, satellite,
fixed wireless, and more. I also now know the characteristics of each of these
internet connection.
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