Communication System Planning Lec 7

8/12/2019 Communication System Planning Lec 7

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Communication System Planning

Passive Optical Networks

TE47 C,D- Spring 2014

LEC MOIZ AHMED PIRKANI


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Lecture OutlineWhy PON as access technologyAdvantages of PONs

PON Standardization

WDM PONs

Advantages of WDM PONs


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Limitations of Current Access

TechnologiesMay suffer bottlenecks in bandwidth-on-demandperformance and service range Cable networks are susceptible to ingress noise;

DSL systems can be plagued with significant crosstalk; Unprotected broadcast wireless links are prone to security

breach and interference.

Downstream transmission rate tends to be much

higherthan the upstream link Restricts Internet applications to mostly Web browsing andfile downloads.


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Passive Optical Networks (PONs)

Optical access networks such as PONs Offer symmetrical data transmission on both the upstream

and downstream links;

Allow end user to provide Internet services e.g.,music/video file sharing, Web hosting

Provide a good alternative and an excellent evolutionarypath for current access technologies.

MetroNetwork

OpticalLine

Terminator(OLT)

ONU

ONU

Splitter/Combiner

Optical Access Network

DSLModem

CableModem

WirelessModem

Coax

Copper

Wireless

ONU

ONU


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Advantages of PONs

By usingpassive components (e.g., opticalsplitters and couplers) and eliminatingregenerators and active equipment normally usedin fiber networks, PONs reduce installation and

maintenance costs of fiber These costs still require laying fiber, which makes PONs

more expensive to install;

However, since fiber is not bandwidth limited but losslimited (as opposed to copper wires, cable, and wireless),potential performance gains and long-term prospects makePONs well-suited fornewneighborhoods or installations.


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TWO FIBER SYSTEM

DOWN STREAM

UP STREAM

= 1260 = 1360

= 1260 = 1360


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SINGLE FIBER SYSTEMDOWN STREAMUP STREAM

= 1260 = 1360 = 1480 = 1580

DOWN

STREAM1UP STREAM

= 1260 = 1360 = 1480 - 1500 = 1539 - 1565

DOWN

STREAM2

DOWN

STREAM1UP STREAM

= 1260 = 1360 = 1480 - 1500 = 1550 - 1560

DOWN

STREAM2

STANDARD BAND

ENHANCED BAND (OPTION I)

ENHANCED BAND (OPTION II)

DIGITAL SERVICES

VIDEO SERVICES


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PON StandardizationGroup called the Full Service Access Network (FSAN) formed byinternational carriers and optical equipment vendors in 1995 developedthe APON spec and proposed it to ITU

By 1999, spec for fundamental APON had been written and approvedby ITU-T (G983.1 and G983.2/Study Group 15)

BPON term introduced to break the myth of ATM as layer 2 protocol forAPON

IEEE for Ethernet-based PON

Efforts to create an EPON standard being driven by IEEE 802.3 Study

GroupGPON, to amalgamate all standards with increased bit rates andservices

Standards are based on data rates and layer 2 protocols


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Standards SummaryStandards are based on data rates and layer 2protocols

GPON specifies all the services to be provided by

PONGPON is still open for recommendations

There is no restriction on ARCHITECTURE andoptical technology (DWDM/CWDM/Single )

The standards dont specify anything on capacityand number of users


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APON ATM PON

FSAN established APON in mid 1990s.

In technical terms, APON supports a 20km length, downstreaminformation at 622 Mbps or 155Mbps, and upstream informationat 155Mbps.

The symmetrical configuration would typically be used forbusiness applications, while the asymmetric configuration wouldbe used for residential applications.

OLT

ONU

ONU

ONUOptical

Splitter


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BPON Broadband PONThe initial PON specifications defined by the FSANcommittee used ATM as their layer 2 signaling protocol. Assuch, they became known as ATM-based PONs or APONs

Use of the term APON led users to believe that only ATMservices could be provided to end-users, so the FSANdecided to broaden the name to Broadband PON. BPONsystems offer numerous broadband services includingEthernet access and video distribution

BPON networks are defined by the FSAN and ITUcommittees comprised of both equipment vendors andservice providers


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EPON Ethernet PONEPON was developed by FSAN in early 2001.

Ethernet PON supports no more than 15km and 10km at 1.25 Gbps data rates.


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GPON Gigabit PONFSAN developed GPON in 2001.GPON provides full service support for various bit rate options using the sameprotocol, including asymmetrical 622 Mbps, 1.25 Gbps, and 2.5 Gbps.


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STANDARDS COMPARISONLayer 2

Protocol

Max Data Rate Reach

Downstream Upstream

APON ATM 155 or

620Mbps

155Mbps 20Km

BPON ATM 155 or

620Mbps

155Mbps

EPON Ethernet 1000Mbps 1000Mbps >= 10Km

GPON None

Specific

1.2 or

2.4Gbps

155Mbps

to 2.4Gbps

20Km


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Benefits and ApplicationsBenefitsFast over long distance Longer xmit distances vs copper

(5.5km vs. 20km)

Future-proof and securityCan use DWDM for highercapacity

Cheaper than point to point Less fiber and lasers

Passive components in outsideplant means less maintenance,power and cost

Good for broadcasting

Applications

High-speed Internet

Video-on-Demand, HDTV,Multimedia entertainment

VPN, Office Productivity Apps

IP Telephony

Remote learning

Aggregate other services like VDSL


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PONs Performance MetricsScalability

Number of Users (NW Capacity)

FlexibilityPower Budget

Cost

Distance


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WDM PONWDM PON makes use of CWDM or DWDM to deliver a unique wavelength toa customer.

WDM PON typically uses arrayed waveguide gratings (AWG) for virtual point-to-point connectivity.

AWGs have a typical insertion loss of 4-5dB, and a small temperaturesensitivity of 0.011nm/oC.


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Why WDM in PON?Network SecurityUpgradeability

Large Capacity

Easy management


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PON Topologies


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Linear Add/Drop LAD)

O

L

T

TSP TSP TSP

SSP

SSP SSP

SSP

ONT ONT

ONT

ONT

ONT

ONT

ONT

ONT

ONT

ONT

ONTONT

ONT

ONTONT

ONT

ONT

ONT

down

up

M

St


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UA DA VO

L

TTrunk Fiber

TSP

SSP

WSP

ONU

WSP

ONU

ONU

ONU ONU

ONU

ONU

TSPTSP

ONU

SSP

WSPONU

WSP

ONU

ONU

ONU

ONU

ONU

ONU

SSP

WSPONU

WSP

ONU

ONU

ONU

ONU

ONU

ONU

SSP

WSP

ONU

WSP

ONU

ONU

ONU

ONU

ONU

ONU

Feeder FiberStage Fiber

Drop Fiber

Stage 1

Stage 2

Stage m

Stage m-1

UA

Down Stream Wavelength

Up Stream Wavelength

Video Wavelength

Physical FiberAll Upstream

DA

V

U1

D1

UG

DG

All Downstream

All Video

One Upstream

One Downstream

Group of Upstream

Group of Downstream

UG DA V UG DA V

UG DA V

UG DA V

UG DA V

UG DA V

U1D1V

U1D1

V U1D1V

U1 D1 V

M-Stage

LAD

DESIGN


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POWER BUDGETVideo Downstream

(20nm S/L band)

Data Downstream

(40 s C band)

Data Upstream

(40 s O band)

Power@Tx 21dBm (After EDFA) 10dBm (Without

AMP)

10dBm

OLT AWG MUX Loss - 3.5dB (1:40 AWG-

100GHz)

- (Using AMP before)

Fiber Loss 2dB

([email protected]/Km)

2dB


4dB


WDM Splitter Loss 4dB ([email protected]) 4dB ([email protected]) 2dB ([email protected])

Loss at Trunk Split Point

(TSP)

6dB max (5.5dB at

Stage 2&3)

6dB max(5.5dB at

Stage 2&3)

6dB max(5.5dB at

Stage 2&3)

Loss at Stage Split Point

(SSP)

17 dB(1:32 Power

Splitter )

3.5dB (1:40 AWG-

100GHz)

10dB (CAWG & 1:4

PS)

Loss at Wavelength Split

Point (WSP)

17dB (1:32 Power

Splitter )

17dB (1:32 Power

Splitter )

17dB (1:32 Power

Splitter )Total Loss 46dB 36dB 39dB

Power@Rx -25dBm -26dBm -29dBm

Receiver Sensitivity -31dBm (@2.5Gbps) -31dBm (@2.5Gbps) -30dBm (@Amplifier)

Excess Power Margin 6dB 5dB 1dB


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AdvantagesFlexibility

Scalability

Bandwidth on Demand

Higher Capacity

High Speed

Multiple Serving EnvironmentPROTOCOL CONTROLED

SUPER USERS PREFERRED/ASSURED USERS

MULTIPLE WAVELENGTHS


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Scalability

Bandwidth on Demand

Higher Capacity

High Speed

Multiple Serving Environment

40 Wavelengths32 users per wavelength

40x32=1280 users/fiber

Voice, video & 75Mbps data


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Scalability

Bandwidth on Demand

Higher Capacity

High Speed



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Scalability

Bandwidth on Demand

Higher Capacity

High Speed



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SERVICESBroadband Services include:

Voice

Telephone Channels

Video TV Channels Broadcast

Interactive Video

Data

the order of 10s of Mbps Symmetrical

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Communication System Planning Lec 7