fiber in the loop (fitl)

Fiber In The Loop (FITL)

FIBER IN THE LOOP (FITL)

SEMINAR REPORT

Submitted in partial fulfilment of the requirements for the award of the degree of Master of Technology in Electronics &

communication (Optoelectronics & Optical communication)

Submitted by

SYAM MOHAN P.M.OPE/M TECH/09-06-14

DEPARTMENT OF OPTOELECTRONICSUNIVERSITY OF KERALA

KARIAVATTOMTHIRUVANANTHAPURAM – 695581

Department of Optoelectronics 1


FIBER IN THE LOOP (FITL)

SEMINAR REPORT

Submitted By

SYAM MOHAN P.M

OPE/M TECH/09-06-14

Submitted in partial fulfilment of the requirements for the award of the degree of Master of Technology in Electronics &

communication (Optoelectronics & Optical communication)

DEPARTMENT OF OPTOELECTRONICSUNIVERSITY OF KERALA

KARIAVATTOMTHIRUVANANTHAPURAM – 69558



DEPARTMENT OF OPTOELECTRONICS

UNIVERSITY OF KERALAKARIAVATTOM

THIRUVANANTHAPURAM – 695581

CERTIFICATE

This is to certify that this report titled “Fiber In The Loop (FITL)” is a bonafide record of the seminar presented by Syam Mohan P.M. (OPE/M TECH/09-06-18) towards the partial fulfillment of the requirements for the award of Degree of Master of Technology in Electronics and Communication (Optoelectronics and Optical Communication) of University of Kerala during the academic period of 2009-2011.

Head of the Department Seminar Guide



ACKNOWLEDGEMENT

First and foremost, I would like to thank God for giving me wisdom and guidance

throughout my life.

I express my heartfelt thanks and deep sense of gratitude to Dr.V.P.Mahadevan

Pillai, Head of the Department, Department of Optoelectronics for his valuable support

and advice.

I am deeply grateful to Dr. K.G. Gopchandran, Lecturer, Department of

Optoelectronics for his valuable and inspiring advices.

I wholeheartedly thank Ms. Aparna John, Mrs. Renju Azeez and all other faculties

of the Department for their valuable guidance and support that they gave me to present

this successfully.

Also I wish to express my special thanks to my family and friends.



This Seminar is dedicated to…...

“The world wide communication network based on optical fibers has truly shrunk the world and brought human beings close together. The news of the Nobel prize reached me in the middle of the night at 3 am in California, through a telephone call from Sweden no doubt carried on OPTICAL FIBER.”

Charles Kao (Father of Fiber optics)



CONTENTS

Chapter no. Chapter name Page no

1 SYNOPSIS 1

2 PRELUDE 2

3 CLASSIFICATION OF FITL 5

3.1 Fiber To The Home (FTTH) 6

3.2 Fiber To The Building (FTTB) 7

3.3 Fiber To The Curb (FTTC) 8

3.4 Factors to choose FTTx Architectures 9

3.5 FTTx Architectures 9

3.6 Passive Optical Network(Point-to-Multipoint) 12

3.6.1 Architecture of PON 12

3.6.2 Network Elements of PON 14

3.6.3 Splitter configurations in PON 15

3.6.4 Features of PON 16

3.6.5 FTTH SERVICE OFFERINGS 17

4 CONCLUSION 18

5 REFERENCES 19



1. SYNOPSIS

Fiber In The Loop (FITL) is given to the system which is based on the fiber

in the access network to provide various services to a subscriber on demand with a

good quality of service and a totally managed system. It is a system implementing

or upgrading portions of the POTS local loop with fiber optic technology from the

central office of a telephone carrier to a remote Serving area interface (SAI)

located in a neighborhood or to an Optical Network Unit (ONU) located at the

customer premises (residential and/or business). Generally, fiber is used in either

all or part of the local loop distribution network. FITL can be implemented with

any FTTx architecture, such as fiber to the curb (FTTC), fiber to the node (FTTN),

and fiber to the premises (FTTP).Residential areas already served by balanced pair

distribution plant call for a trade-off between cost and capacity. The closer the

fiber head, the higher the cost of construction and the higher the channel capacity.

In places not served by metallic facilities, little cost is saved by not running fiber

to the home.


http://en.wikipedia.org/wiki/Plain_old_telephone_service

http://en.wikipedia.org/wiki/FTTx

http://en.wikipedia.org/wiki/Local_loop

http://en.wikipedia.org/wiki/Serving_area_interface

http://en.wikipedia.org/wiki/Telephone_exchange

http://en.wikipedia.org/wiki/Optical_fiber

http://en.wikipedia.org/wiki/Local_loop


2. PRELUDE

Introducing the fiber in the local loop was envisaged nearly 20 years ago.

As the quality of the optical fiber was improving, efficient transmitters and

receivers appeared; it seemed possible to build an access network that would be

based on the optical technology. Due to the lack of active units in the light path the

architecture of the system was simple, cost effective and offered bandwidth that

was not, and still is not, possible to achieve by other access methods.

However, the initial progress in the development of optical networks was

slowed to a halt by economical and technological factors. The Internet was not as

widespread then as it is now and customers were not ready to pay for the

broadband access. It was envisaged that a narrow band Integrated Services Digital

Network access would be sufficient for most of the users until year 20104 and

only handful of business customers would need broadband access.

Rapid progress in development of different types of the Digital Subscriber

Loop (DSL) technology and its widespread adoption in the nineties was another

factor impeding the deployment of FTTH. As the average transfer rate of 6Mbps

could be achieved over DSL, the cost of replacing existing copper infrastructure

with optical cables was not justified from the economical point of view. The

twenty-first century heralded countless changes across our landscape; arguably

none will be more important than the transformation of our telecommunications

providers means to deliver consumers, both residential and business,

telecommunication services. This phenomenon is being underpinned by two

technologies; Internet Protocol commonly referred to as IP and optical fiber.



Today, the technology is available to provide all classes of service, voice, video

and data, over a common protocol; IP.

Carriers are quickly moving to maximize the number of services they offer

to a single customer via a bundled offering. Technologies such as VoIP, IPTV and

broadband are becoming commonplace across our society. As bundled services

and technologies are deployed, carriers are realizing that their original networks,

designed to efficiently deliver a single service, are stressed and in many cases

incapable of offering the desired services. Figure 1 depicts forecasted subscriber

service and bandwidth demand (note new compression schemes include MPEG-4

and Microsoft Windows 9/VC1). Today’s networks are being designed to provide

20+Mbps while 3-5 years from now carriers will need 40+Mbps capability as

multiple services are used in the home, HDTV becomes more prevalent and users

demand faster internet connections. This is resulting in the largest investment in

the access network since the turn of the century and the wiring of the western

world for voice services Leading this investment wave is the deployment of

single-mode optical fiber deeper into these access networks in order to curb the

thirsty bandwidth requirements of their customers. Increasingly, carriers are

finding that deploying the fiber all the way to the customer enables network future

proofing, maximizes the symmetrical bandwidth throughput of a carrier’s access

network, provides for network reliability, reaps significantly reduced operating

expenses and affords enhanced revenue opportunities. The industry refers to this

technology as FTTH.

The deployment of optical fiber in an access network can be achieved in

multiple ways. In fact, many access technologies are commonly referred to as

FTTx when in fact they are simply combinations of optical fiber and twisted pair

or coaxial cable networks. These technologies do not provide for the inherent

capability of a FTTH network. Nonetheless it will be useful for us to discuss them



later in this report. The speeds of fiber optic and copper cables are both limited by

length, but copper is much more sharply limited in this respect. For example,

gigabit Ethernet runs over relatively economical category 5e, category 6, or

augmented category 6 unshielded twisted pair copper cabling but only to 100

meters. However, over the right kind of fiber, gigabit ethernet can easily reach

distances of tens of kilometers.

Even in the commercial world, most computers have copper

communication cables. But these cables are short, typically tens of meters. Most

metropolitan network links (e.g., those based on telephone or cable television

services) are several kilometers long, in the range where fiber significantly

outperforms copper. Replacing at least part of these links with fiber shortens the

remaining copper segments and allows them to run much faster.

Fiber configurations that bring fiber right into the building can offer the

highest speeds since the remaining segments can use standard Ethernet or coaxial

cable. Fiber configurations that transition to copper in a street cabinet are generally

too far from the users for standard Ethernet configurations over existing copper

cabling.


http://en.wikipedia.org/wiki/Category_6a

http://en.wikipedia.org/wiki/Category_6

http://en.wikipedia.org/wiki/Category_5e

http://en.wikipedia.org/wiki/Gigabit_Ethernet


3.CLASSIFICATION



3.1 Fiber To The Home (FTTH)

It is a method of installing optical fiber cable to the home. FTTH consists of

a single optical fiber cable from the base station to the home. All FTTH networks

inherently are designed to deliver an optical fiber to the subscriber. Their design

though is highly dependent on the unique nature of the access environment; hence

product and design flexibility is critical. At their core FTTH networks contain an

optical line terminal (OLT), optical cable and an optical network terminal (ONT).

Various other specialized components are added to address the unique nature of

the access network. Both OLTs and ONTs are active devices.



3.2Fiber To The Building (FTTB)

Optical fiber cables extending from an Optical Line Terminal (OLT) unit

located in CO to an Optical Network Unit (ONU) or Remote Terminal (RT) at the

boundary of the apartment or office or building. The optical fiber terminates

before reaching the home living space or business office space and where the

access path continues to the subscriber over a physical medium other than optical

fiber (for example copper loops). Optical fiber cable is extended up to the metallic

cable installed within the building. A LAN or existing telephone metallic cable is

then used to connect to the user.



3.3 Fiber To The Curb (FTTC)

A method of installing optical fiber cable by the curb near the user’s home.

An optical communications system is used between the Remote Unit (O/E)

installed outside such as near the curb or on a telephone pole) from the Central

Office. Coaxial or other similar cable is used between the remote unit and user.

FTTC typically pushes fiber 500-1000 feet from the subscriber terminating at an

RT and will serve 8-12 subscribers. Fiber to the curb (FTTC) is a

telecommunications system based on fiber-optic cables run to a platform that

serves several customers. Each of these customers has a connection to this

platform via coaxial cable or twisted pair.


http://en.wikipedia.org/wiki/Twisted_pair

http://en.wikipedia.org/wiki/Coaxial_cable

http://en.wikipedia.org/wiki/Optical_fiber


3.4 Factors to choose FTTx Architectures

existing outside plant

network location

cost of deploying the network



subscriber density

Return on investment (ROI).

3.5 FTTx Architectures

Active FTTx Architectures

Home Run Fiber

Active Star Ethernet

Passive FTTx Architectures

Passive Optical Networks (PONs)

Home Run Fiber (Point-to-Point)

A dedicated fiber from an Optical Line Terminal (OLT) unit located in the

Central Office (CO) connects to an Optical Network Terminal (ONT) at each

premise. Both OLTs and ONTs are active, or powered, devices, and each is

equipped with an optical laser. Distance between subscribers CO or OLT as 80km,

Each subscriber is provided a dedicated “pipe” that provides full bi-directional

bandwidth. It Requires the installation of much more fiber than other options. The

fiber cost and size of the fiber bundle at the OLT can make this network expensive

and inconvenient in many service areas.



Point To Point

CO

User’s Premise

Point To Point

CO

User’s Premise

Home Run Fiber Architecture

Active Star Ethernet (Point-to-Multi Point)

Multiple users share one feeder fiber through a remote node located

between the CO and the served premises. Remote node can be shared between

four to a thousand homes via dedicated distribution links from the remote node.

Subscriber location can be upto 80km. Each subscriber is provided a dedicated

“pipe” that provides full bidirectional bandwidth. It Requires less amount of fiber



ASE has the benefits of standard optical Ethernet technology, much simpler

network topologies and supports a wide range of CPE solutions.

P2M Switched

EthernetCO

User’s Premise

P2M Switched

EthernetCO

User’s Premise

Active Star Ethernet Architecture

3.6 Passive Optical Network(Point-to-Multipoint)

Passive Optical Network is essentially a cost effective optical fiber based

access system for providing multi-play (voice, video, data etc) services, being

rolled out by BSNL shortly, to both business and residential customers. A Passive

Optical networks (PON) use optical fiber and optical power splitters to connect the

Optical Line Terminal (OLT) at the local exchange to the subscriber’s Optical

Network Unit (ONU) on his premises. No electrical or electronic components are



used between these points. This approach greatly simplifies network operation &

maintenance, and reduces the cost. Another advantage is that much less fiber is

required than in point-to point topologies

3.6.1Architecture of PON

One OLT resides in Central Office that is connected to backbone network.

Multiple Optical Network Units(ONU) connect to OLT by a single wavelength

channel and is connected to back end users. Ethernet is an inexpensive technology

that was applied to PON to get cost effective bandwidth. Technology used to

create a passive optical infrastructure: Ethernet technology. PONs builds a point-

to-multi-point fiber topology that supports a speed of Gbps for up to 20 km. While

subscribers are connected via dedicated distribution fibers to the site, they share

the Optical Distribution Network (ODN) trunk fiber back to the Central Office.



3.6.2 Network Elements of PON

• OLT

• ONU/ONT

• PON SPLITTERS

OLT

OLT resides in the Central Office (CO). Provides aggregation and

switching functionality between the core network (various network interfaces) and

PON interfaces. The network interface of the OLT is typically connected to the IP

network and backbone of the network operator. Multiple services are provided to

the access network through this interface.

ONU/ONT

An External Plant / Customer Premises equipment providing user interface

for many/single customer. Access node installed within user premises for network

termination is termed as ONT. Access node installed at other locations i.e.

curb/cabinet/building, are known as ONU. ONU/ONT provide, user interfaces

(UNI) towards the customers and uplink interfaces to uplink local traffic towards

OLT .

PON Splitter

PONs are distributed or single staged passive optical splitters/combiners.

It provides connectivity between OLT & multiple ONU/ONTs through one or two

optical fibers. Optical splitters are capable of providing up to 1:64 optical split, on



end to end basis. These are available in various options like 1:4, 1:8, 1:16, 1:32

and 1:64.

3.6.3 Splitter configurations in PON

Centralized Splitter

1x32 splitter is used in an outside plant enclosure such as a fiber

distribution terminal.

Cascaded Splitter

More than one splitter location in the pathway from central office to

customer. Standard splitter formats range from 1 x 2, 1 x 4, 1 x 8, 1 x 16 and 1 x

32 so a network might use a 1 x 4 splitter leading to a 1 x 8 splitter further

downstream in four separate locations. Optimally, there would eventually be 32

fibers reaching the ONTs of 32 homes



3.6.4 Features of PON

Point-to-multipoint fiber-lean architecture Instead of running a separate

strand of fiber from the CO to every customer. uses a single strand of fiber

to serve up to 32 subscribers .

It uses Optical Fibers so that the bandwidth is high, can reach longer

distances.

Low cost of equipment per subscriber.

Passive components require little maintenance and have a high MTBF

(Mean Time Between Failure).

Additional buildings can be added to the network easily and inexpensively.

It supports a broad range of applications including triple play (voice, data,

video) over a single fiber and FTTB, FTTC, FTTH.

ItOffers a large amount of high speed bandwidth providing greater

flexibility for adding future services.



Flexible and scalable bandwidth assignment.

3.6.5 FTTH Service Offerings

Video over IP (MPEG2)

Video on Demand (VoD) (MPEG4)

Audio on Demand

Bandwidth on Demand (User and or service configurable)

Remote Education

Point to Point and Point to Multi Point Video Conferencing

Voice and Video Telephony over IP



Interactive Gaming

Layer 3 VPNs

VPN over broadband

Dial-up VPNs

Virtual Private LAN Services (VPLS)

4 . CONCLUSION

“Fiber Access Network

Finally beating the bandwidth game”



5. References

www.ftthcouncil.org

Dr.John Mitchell, University College London, UK, “Getting

Fiber To The Home”.

“Genexis” FTTH Network Architecture.

“CISCO” FTTH technology considerations, Wolfgang

Fischer.



www.corning.com

FTTH: The Overview of Existing Technologies by Dawid

Nowaka and John MurphybaSchool Of Electronic

Engineering, Dublin City University, Dublin 9

FTTH Explained: Delivering efficient customer bandwidth

and enhanced services Michael Kunigonis Product Line

Manager Access Corning Cable Systems


http://www.corning.com/

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