This document discusses cable internet and how it works. It begins by introducing cable modems and how they connect computers to the internet through existing coaxial cables used for cable TV. It then explains how cable internet networks are configured, with tuners, demodulators, and modulators allowing data to be transmitted over cables in both directions. Key components include cable modem termination systems at hubs that direct traffic between users and ISPs. Cable internet provides high-speed, shared access but availability depends on cable infrastructure and speeds may decrease during peak usage times.

1. PRESENTED BY:-
Aman Kumar Singh
Ashwani Chaturvedi
CSE-3rd YEAR
G.L.B.I.T.M.
Greater Noida

2.  Introduction
 Cable Modem
 Broadband In India
 Evolution of Cable Internet
 Cable Internet Working
 About Cables Configuration
 Advantages of Cable Internet
 Disadvantages of Cable Internet
 Conclusion

3.  Internet is a networks of network(Global n/w)
 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,
offering a vast network for control the internet access.
 Use the dial-up telephone services provided by your
Cable Company in conjunction with a modem.

6.  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.

7.  Tuner: it with the help of splitter separates Internet data fron CATV
programming, diplexer uses (40 to 850Mhz) for downstreaming and (5 to
45Mhz for upstreaming
 Demodulator : Radio-frequency to simple signal for analog to digital
converter,error correction module, network frames in MPEG format to oder
the data.
 Modulator: network signal to radio frequency, error correction info, D/A
converter, QAM.
 MAC: interface between hardware and software portions of protocols,some
tasks of MAC is passed to CPU unit

10. Coaxial cables
 Center core- material copper
 Insulating dielectric – It
separates the two conducting
wires
 Metallic shield – it provides
flexibility as well as reduce
interference
 Plastic jacket- provides cover
from external moisture

12.  Separates single high optical fibre into two cables
1. broadband cable
2. tv cable
• Splitter can also be used in the local systems
• Locally high bandwidth needed system are separated

13. Cable TV NETWORK
 Internet connection is through existing cables lines
which is done through CATV
 Cable Tv networks are of high bandwidth in range of
550Mhz to 750Mhz
 Need for setup of two way line with high frequencies
towards the subscriber
 Setup needs-
1. Cable modem
2. Cable modem termination system
3. Coaxial cables
4. Splitter

14.  Each channel of program is given 6MHz slice of bandwidth
 ISPs divide the channel into two streams for internet:
- Downstream- takes 6Mhz same as any program channel, used
use for downloading
- Upstream - takes 2Mhz as user upload less
 Stream dividing needs
- Cable modem
- Cable Modem Termination System(CTMT)

15. A cable modem termination system or CMTS is a piece
of equipment, typically located in a cable company's
headend or hubsite, which is used to provide high speed
data services, such as cable Internet or Voice over
Internet Protocol, to cable subscribers.

16.  Directs traffic from users to ISPs for connection
 At head end, cable providers lease for a third party
ISP, servers for accounting and logging
 Dynamic Host Configuration Protocol(DHCP) for
assigning and administrating all IPs of cable
system users, control servers for a protocol called
Data Over Cable Service Interface
Specifications(DOCSIS)
 Downstream data flows to every user but
upstream data is only read by CTMS others don’t
see that data, upstream bandwidth is divided by
time in millisecond

17.  DOCSIS(Data over cable Service Internet
Specification)
 Supports bidirectional 27mbps speed over
network
 Applied in datalink and network layer, few
packet collision compared to cdma-cd
 It adds IPv6 mangement

18.  Distributing IP addresses for systems
 Static allocation
 Dynamic allocation of IP address
 Maintain a tables of IP addresses for IP
allocation

19.  No dialup connection needed
 Higher speeds up to theoretical 38Mbps
 Infrastructure cost is less
 High bandwidth at low cost
 High penetration
 Doesn’t disintegrate with distance
 Performance doesn’t depend on distance
from central cable office.
 High bandwidth to low cost

20.  Shared connections – lower speeds at peak hours
 High pricing as compared to DSL networks
 Needs a better cable infrastructure in rural areas
 Traffic congestion on the net
 Higher security risk than dialup
 Always on Connectivity
 Usually tied with cable TV subscription

21. 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.

22. THANK
YOU