38812717 Internet Access via Cable Tv Networks

8/6/2019 38812717 Internet Access via Cable Tv Networks

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INTERNET ACCESS

VIA CABLE TV

NETWORKS

Sibananda mahanta

0701222279

Branch-information Technology


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Contents : Introduction How to Access Internet using Cable TV Network

Cable Modem Changes in Cable Network Connection Work Of Cable Modem Isolation of TV & PC

How Fast is Cable Modem Real-World Performance

Ethernet over Coaxial Adapter Advantages and Disadvantages Applications

Conclusion


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Internet data can be transferred through Cable networks

wired to the user computer.

Accessing the Internet at 10 megabits per second.

A cable modem connects to a PC using the same coaxial

cable that brings all channels to your television.

India has a cable penetration of 80 million homes, offeringa vast network for leveraging the internet access.

INTRODUCTIONINTRODUCTION


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Use the dial-up telephone services provided

by your Cable Company in conjunction with a

modem or ISDN adapter.

To use a Cable modem

How to access the InternetHow to access the Internet

using the Cable Networkusing the Cable Network


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Cable modem and ISDN AdapterCable modem and ISDN Adapter

Cable modem ISDN Adapter


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A "Cable Modem" is a device that allows high-speed access

to the Internet via a cable TV (CATV) network.

The cable modem attaches to computer through an

Ethernet Network Interface Card.

It takes a signal from the computer and converts it for

transmission over the cable network

Cable ModemCable Modem


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Changes in the CableChanges in the Cable

NetworkNetwork The cable network was designed to deliver TV signals in

one direction from the Head-End to the subscribers homes. To provide TV services Cable Operators had to recreate a

portion of the over-the-air radio frequency (RF) spectrum

within a sealed coaxial cable line.

Operators had to upgrade the cable network so that signals

could flow in both directions.

Cont..


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Cable Operators assign a spectrum of signal frequencies to the cable

network.

One spectrum is used for the signals that move from the Head-End

towards the cable subscriber.

Another spectrum of signal frequencies are used for the signals that

move from the cable subscriber towards the Head-End.

By replacing existing one way amplifiers with two way amplifiers Cable

Operators are able to separate the upstream and downstream signals

and amplify each direction separately in the right frequency range


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How does it connect?How does it connect?

A Traditional Cable network Cont..Cont..


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A Modern Cable network Cont..Cont..


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Ethernet 10BaseT is emerging as the mostpredominant method.


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How Cable Modem WorkHow Cable Modem Work

Your Cable Company supplies you with a connection to your home which in

turn is connected to a splitter box.

One spur from the splitter box is connected to your TV through a TV

Adapter, the other being connected to your Cable Modem, which in turn

is connected to your computer through an Ethernet connection.

Cable modems can be part modem, part tuner, part encryption /

decryption device, part bridge, part router, part NIC card and part

Ethernet hub.


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Isolation of TV & PCIsolation of TV & PC

At the connecting point the feeding of the data into the TV cable

network.

The modem with an Ethernet interface.

They will be connected by means of a splitter at the system

outlet of the subscriber.

The system uses the frequency range from 5 MHz until 30 MHz,

which is not used from TV programs.


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How fast is a Cable ModemHow fast is a Cable Modem

Cable modem speeds vary widely

Depends on the cable modem system

Cable network architecture

Traffic load.

In the downstream direction (from the network to the computer), network speeds

can be up to 27 Mbps

BUT, this is an aggregate amount of bandwidth that is shared by users.

Few computers will be capable of connecting at such high speeds or have exclusive

access to the network

A more realistic number is 1 to 3 Mbps.

Cont..Cont..


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In the upstream direction (from computer to network), speeds can be up

to 10 Mbps.

However, most modem producers have selected a more optimum

speed between 500 Kbps and 2.5 Mbps

AND, many cable operators limit the upstream bandwidth to 128 or

384kbs

An asymmetric cable modem scheme is most common. The downstream

channel has a much higher bandwidth allocation (faster data rate) than

the upstream,

primarily because Internet applications tend to be asymmetric in nature.

Cont..Cont..


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Activities such as World Wide Web (http) navigating

and newsgroups reading (nntp) send much more data

down to the computer than to the network. Mouse clicks (URL requests) and e-mail messages are

not bandwidth intensive in the upstream direction.

Image files and streaming media (audio and video) arevery bandwidth intensive in the downstream direction.


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RealReal--World PerformanceWorld Performance

The theoretical performance of a Cable Modem is based upon all other

devices being able to work at the same speed and performance as the

Cable Modem.

However, in a similar way that the actual usable bandwidth on a 10Mbps

Ethernet connection reduces to a 4Mbps, so too will the performance of

a Cable Modem connection be reduced.

The Cable network itself will suffer the same problems of Internet

performance as any other Internet Service Provider (ISP).

Cont..Cont..


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RealReal--World PerformanceWorld Performance

Although performance to services on the cable network

itself can be amazingly fast, access to 'the outside world'

will be slowed down by the performance of otherconnections on the way.

As usage on your segment grows (as more customers are

added) the bandwidth must be shared by more people.


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Support for Multiple PCsSupport for Multiple PCs

A cable modem can provide Internet access to multiple PCs,

if they are connected via a local area network (LAN)

Cable modems typically have an Ethernet output, so theycan connect to the LAN with a standard Ethernet hub or

router

Each PC must have an assigned IP address

The cable ISP usually sells at a premium of $5-$10 a

month per PC

NAT (Network Address Translation) can allow multiple

PCs to "hide" behind a single IP Address


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Ethernet over Coax AdapterEthernet over Coax Adapter

Ethernet Coaxial Adapter :-


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Ethernet over Coax AdapterEthernet over Coax Adapter

The Ethernet over Coax adapter provides a simple and inexpensive way

to create a reliable home network, without running CAT5 cables through

your walls.

It delivers high speed internet, voice and video over coaxial cable.

Ideal for homes, apartment buildings or hotels seeking to add high-

speed internet capabilities over existing coaxial TV cables.


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AdvantagesAdvantages

High Availability

High Bandwidth to Low Coast

High Speed Data Access

Always on Connectivity


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LimitationLimitation

Cable connections are not available in every

neighbourhood, Because cable connections are

Always on, one needs a firewall and activation of

other security features so as to protect the

computer


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ApplicationsApplications

Connect set-top boxes, personal computers, game consoles,

broadband modems etc. to your home network instantly.

Add high-speed internet, digital voice and video access to

any room with a coaxial TV cable.

Ideal for homes, apartment buildings or hotels seeking toadd high-speed.


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ConclusionConclusion

Cable TV has a strong reach to the homes and therefore offering

the Internet through cable be a scope for furthering the growth

of internet usage in the homes.

The cable is an alternative medium for delivering the Internet

Services in the US, there are a million homes with cable modems,

enabling the high-speed internet access over cable


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QUERIES ???QUERIES ???


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THANK U


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38812717 Internet Access via Cable Tv Networks

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