# Presentation: 357086

## Fiber-to-the-HomeOverview & Technical Tutorial

- Jim Farmer, Vice President
- Leonard Ray, Government Relations Committee Chairman

- Fiber-to-the-Home Council

## Fiber-to-the-Home (FTTH)Overview and technical tutorial

- The FTTH Council
- FTTH market overview
- FTTH technical tutorial
- Standards update
- Questions

## The FTTH CouncilVisit us on the web at www.ftthcouncil.org

- Mission:
- Educate, promote & accelerate FTTH and the resulting quality-of-life enhancements
- Objectives:
- Supply a consistent and accurate view of FTTH
- Promote FTTH market development
- Be recognized by the industry as _the_ FTTH resource
**78 member companies, organizations and individuals**
- We represent the interests of those interested in FTTH
- Our members are from every telecommunications group
- We do not represent any one group

## The FTTH Council Represented in every layer of the FTTH value chain

**The FTTH Council *****Represented in every layer of the FTTH value chain***

**Retail provider**

**Wholesale provider**

**Network owner**

**Network  construction**

**Content aggregator**

**Content provider**

**OEM **

**Feasibility consultants **

**ROW owner**

**Financial consultants**

**Network design**

**Project management**

**Funding**
**source**

**Our members include service providers (RBOCS, CLECs, Municipalities, and Rural LECs), network design and construction companies, financial consultants, and equipment manufacturers.  **

## Fiber-to-the-Home (FTTH)Overview and technical tutorial

- The FTTH Council
- FTTH market overview
- FTTH technical tutorial
- Standards update
- Questions

## FTTH overviewList of ‘US Optical Fiber Communities’*

_**Alabama**_
**Sylacauga**
_**California**_
**Amerige Heights**
**Canyon Hills**
**Kenwood**
**Parc Metropolitan**
**Palo Alto**
**Poppy Measdoss**

- * 	many more 	in construction 	and pre-		construction

**Roseville**
**Sacramento **
**Talavera**
_**Colorado**_
**Buckhorn Valley **
**Colorado City**
**Eagle Ranch**
**Rye**
_**Florida**_
**LPGA Community**

_**Kansas**_
**Almena**
**Hill City**
**Norton**
**Osborne**
**Quinter**
**Sharon**
**Wakeeney**
**Wamego**
_**Massachusetts**_
**Pine Hils**
**Tauton**
_**Michigan**_
**Cobblestone**
_**Minnesota**_
**Alberta**
**Chokio**
**East Ottertail**
**Evermoor**
**Morris**
_**Nebraska**_
**Blair**

_**Oklahoma**_
**Hinton**_** **_
_**Oregon**_
**Woodburn**
_**Pennsylvania**_
**Kutztown**
_**South Carolina**_
**Daniel Island**
**Sandy Point**
_**Texas**_
**Burleson**
**Laredo**
**Canyon Gate Brazos**
**Lakes on Eldridge**
**Northpointe**
**Rock Creek**
**Grand Lake Estates**
**Victory Lakes**
**Crystal Falls**
_**Utah**_
**Kamas**
**Provo**

_**Georgia**_
**Dunwoody**
_**Iowa**_
**Cambridge**
**Guthrie Center**
**Huxley**
**Slater**
_**Idaho**_
**Bear Creek**

_**Virginia**_
**Ashburn**
**Brambleton**
**Braemar-Bristow**
**Bristol**
**Leesburg**
**Purcellville**
_**Washington**_
**Chelan County**
**Douglas County**
**Grant County**
**Issaquah Highlands**
**Mason County**

## FTTH overviewFTTH homes passed in US and Canada

- Source:  	Render, Vanderslice			& Associates

**Greenfield**

**29%**

**Overbuild**

**71%**

- 2002 FTTH networks

**110,000 as of March, 2003**

## FTTH overview FTTH homes connected in US and Canada

## Fiber-to-the-Home (FTTH)Overview and technical tutorial

- The FTTH Council
- FTTH market overview
- FTTH technical tutorial
- Standards update
- Questions

## FTTH technical tutorialWhat is FTTH? 

**Copper**

**Fiber**

**24 kbps - 1.5 Mbps**

**Old networks, optimized for voice**

**//**

- Note: network may be aerial 	or underground

## FTTH technical tutorialWhat is FTTH?

- “An OAN in which the ONU is on or within the customer’s premise.  Although the first installed capacity of a FTTH network varies, the upgrade capacity of a FTTH network exceeds all other transmission media.”
- OAN:  	Optical Access Network
- ONU:  	Optical Network Unit
- OLT:	Optical Line Termination

**CO/HE**

**//**

- ONU

- OLT

- Source:  www.ftthcouncil.org

- OAN

## FTTH technical tutorialWhat is FTTH?

**CO/HE**

- Optical fiber and lasers

- Architecture
- (Electronics)
- - PON?
- - Active node?
- - Hybrid?

- Transport
- - ATM?
- - Ethernet?

- Philosophy
- - Retail
- - Wholesale

- Technical considerations

**//**

## FTTH technical tutorialWhy FTTH?

- Enormous information carrying capacity
- Easily upgradeable
- Ease of installation
- Allows fully symmetric services
- Reduced operations and maintenance costs
- Benefits of optical fiber:
- Very long distances
- Strong, flexible, and reliable
- Allows small diameter and light weight cables
- Secure
- Immune to electromagnetic interference (EMI)** **

## FTTH technical tutorialWhy FTTH? - more capacity*

- * Typical system capability for 100 m link

- Source:  Corning Incorporated

## FTTH technical tutorialWhy FTTH? - longer distances*

**FTTH technical tutorial*****Why FTTH? - longer distances****

- * Typical distance for 1 Gbps system capability

- Source:  Corning Incorporated

## FTTH technical tutorialWhy FTTH? - symmetric services

- Source:  	Grant County Public Utility 	District

- Outbound Internet bursting to 80Mbps
- Inbound Internet (download) averaging about 35-40Mbps
- Upstream is consistently twice the download

## FTTH technical tutorialWhy FTTH? - fiber versus copper

- A single copper pair is capableof carrying 6 phone calls
- A single fiber pair is capable ofcarrying over 2.5 millionsimultaneous phone calls(64 channels at 2.5 Gb/s)
- A fiber optic cable with the sameinformation-carrying capacity (bandwidth) as a comparable copper cable is less than 1% of both the size and weight

- Source:  Corning Incorporated

## FTTH technical tutorialWhy FTTH? - fiber versus copper

- _Glass_
**Uses light**
**Transparent**
**Dielectric material-nonconductive**
**EMI immune**
**Low thermal expansion**
**Brittle, rigid material**
**Chemically stable**

- _Copper_
**Uses electricity**
**Opaque**
**Electrically conductive material**
**Susceptible to EMI**
**High thermal expansion**
**Ductile material**
**Subject to corrosion and galvanic reactions**

**Fortunately, its recyclable**

**//**

## FTTH technical tutorialHow do optical fibers work?

- Carries the light signals
- Silica and a dopant
- Cladding
- Keeps the light in the core
- Pure Silica
- Coating
- Protects the glass
- Acrylate (plastic)

**FTTH technical tutorial*****How do optical fibers work?***

- Source:  Corning Incorporated

## FTTH technical tutorialHow do optical fibers work?

- Optical fibers work on the principle of  total internal reflection
- Light waves (“modes”) are reflected and guided down the length of an optical fiber

- Source:  Corning Incorporated

**CORE**

**CLADDING**

## FTTH technical tutorialTypes of lasers used

- There are two laser technologies that are used for nearly all single mode communications applications
- Fabry-Perot (F-P) lasers
- Lower in cost, lower in power
- Poorer wavelength stability
- Distributed Feedback (DFB) lasers
- Higher cost, higher power
- Excellent wavelength stability
- Excellent temperature stability
- Internally modulated
- Good for moderate powers and distances
- Externally modulated
- Ultimate today for quality in broadcast applications
- Vertical Cavity Surface Emitting Lasers (VCSELs)
- Coming technology, promises lowest costs

## FTTH technical tutorialTypes of lasers used

- Wavelengths used for Single Mode Fiber (long distances) communications
- 1310 nm
- Usually lowest cost lasers
- Used for shorter broadcast runs and short to moderate data runs
- 1550 nm
- Can be amplified with relatively low-cost erbium doped fiber amplifiers (EDFAs)
- Lasers are fabricated on a number of different wavelengths (about 1535 – 1600 nm) for wave division multiplexing (WDM) applications
- Slightly lower fiber loss at 1550 nm
- 1490 nm
- Increasingly popular for downstream data in 3 systems.
- Cannot be amplified as easily
- Somewhat higher device cost

## FTTH technical tutorialSingle and Dual Fiber Systems

- Single Fiber
- Downstream broadcast* on 1550 nm
- Upstream data on 1310 nm
- Downstream data on either 1310 or 1490 nm* depending on system
- Advantages
- Less fiber deployed
- Fewer optical passives (taps or splitters)
- Fewer labor-intensive connections

- * 	Downstream data can be carried at 1550 nm if not used for broadcast

## FTTH technical tutorialSingle and Dual Fiber Systems

- Dual Fiber
- Various plans, usually one fiber will be used for downstream and one for upstream, or one will be used for broadcast and one for data.  Sometimes one will be used for specialized services, such as returning RF-modulated data from set top terminals
- Advantages
- Simplifies terminal passive components
- Somewhat lower signal loss

## FTTH technical tutorialWhat is FTTH?

**CO/HE**

- Architecture
- (Electronics)
- - PON?
- - Active node?
- - Hybrid?

- Transport
- - ATM?
- - Ethernet?

- Philosophy
- - Retail
- - Wholesale

- Technical considerations

**//**

- Optical fiber and lasers

## FTTH technical tutorialTransport - ATM

**Destination**

**header**

**53 byte *****cell***

**Data**

**Next cell**

**5B**

## FTTH technical tutorialTransport - ATM

- Connection-oriented protocol with excellent QOS
- When a connection is made, it exists for the entire communication session, ensuring a reliable channel

**FTTH technical tutorial*****Transport - ATM***

## FTTH technical tutorialTransport - Ethernet

**Preamble **

**& SFD**

**Destination **

**address**

**Source **

**address**

**Data and pad**

**Frame **

**check**

**Type/length**

**Idle until the **

**next cell arrives**

**8**

**4**

*Packet* of data

**6**

**6**

**2**

**up to ~1500 bytes**

## FTTH technical tutorialTransport - Ethernet

- Connectionless-oriented, with excellent efficiency
- Packets are transmitted individually, requiring resources only when they are being transmitted

**FTTH technical tutorial*****Transport - Ethernet***

## FTTH technical tutorialWhat is FTTH?

**CO/HE**

- Architecture
- (Electronics)
- - PON?
- - Active node?
- - Hybrid?

- Transport
- - ATM?
- - Ethernet?

- Philosophy
- - Retail
- - Wholesale

- Technical considerations

**//**

- Optical fiber and lasers

## FTTH technical tutorialArchitectures

*Passive Optical Networks (PONs)*
- Shares fiber optic strands for a portion of the networks distribution
- Uses optical splitters to separate and aggregate the signal
- Power required only at the ends
*Active Node*
- Subscribers have a dedicated fiber optic strand
- Many use active (powered) nodes to manage signal distribution
*Hybrid PONs*
- Literal combination of an Active and a PON architecture

## FTTH technical tutorialArchitectures – PON (A-. E- or G-)

**FTTH technical tutorial*****Architectures – PON (A-. E- or G-)***

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**ONU**

**OLT**

**Optical splitter**
**1x16 (1x2, 1x8)**
**1x32 (1x4, 1x8)**

**Usually 10-20 km**

## FTTH technical tutorialArchitectures – PON (2) (A-. E- or G-)

**FTTH technical tutorial*****Architectures – PON (2) (A-. E- or G-)***

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**1550 nm broadcast (if used)**

**1490* nm data**

**1310 nm data**

- * Data may be transmitted at 1550 nm if not used for video

**ONU**

**OLT**

## FTTH technical tutorialArchitectures – Active Node

**FTTH technical tutorial*****Architectures – Active Node***

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**ONU**

**Processing (powered)**

**Up to 70 km**

**Up to 10 km**

**OLT**

## FTTH technical tutorialArchitectures – Active Node (2)

**FTTH technical tutorial*****Architectures – Active Node (2)***

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**1550 nm broadcast (if used)**

**Data, 1310 or 1550 nm (depending on distance) on separate fibers**

**OLT**

**ONU**

## FTTH technical tutorialArchitectures – Hybrid PON

**FTTH technical tutorial*****Architectures – Hybrid PON***

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**ONU**

**OLT**

**Processing (powered)**

**Up to 70 km**

**//**

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**Up to 10 km**

**Optical splitter**

**Optical splitter**

## FTTH technical tutorialArchitectures – Hybrid PON (2)

**FTTH technical tutorial*****Architectures – Hybrid PON (2)***

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**1550 nm broadcast**

**Data, 1310 or 1550 nm (depending on distance) on separate fibers**

**Single fiber, 1550 broadcast, 1310 bidirectional data**

**OLT**

**ONU**

## FTTH technical tutorialWhat is FTTH?

**CO/HE**

- Architecture
- (Electronics)
- - PON?
- - Active node?
- - Hybrid?

- Transport
- - ATM?
- - Ethernet?

- Philosophy
- - Retail
- - Wholesale

- Technical considerations

- Optical fiber and lasers

## FTTH technical tutorialPhilosophy

- Two types of FTTH networks exist today
- Retail
- Vast majority of FTTH builds today
- Network owner sells services directly to subscribers
- Follows traditional telecommunications and cable television models
- Wholesale
- Market created by a few state laws
- Network owner sells capacity to multiple providers who in turn sells services to subscribers
- Only examples in US today are some municipal FTTH networks

## FTTH technical tutorialWhat is FTTH?

**CO/HE**

- Architecture
- (Electronics)
- - PON?
- - Active node?
- - Hybrid?

- Transport
- - ATM?
- - Ethernet?

- Philosophy
- - Retail
- - Wholesale

- Technical considerations

- Optical fiber and lasers

**//**

## FTTH technical tutorialTechnical considerations

- Data
- How much per home?
- How well can you share the channel?
- Security – how do you protect the subscriber’s data?
- What kind of QoS parameters do you specify?
- Compatible business services?
- SLAs
- T1
- Support for voice?
- Support for video?
- Broadcast
- IPTV

## FTTH technical tutorialTechnical considerations

- Data
- How much per home?
- How well can you share the channel?
- Security – how do you protect the subscriber’s data?
- What kind of QoS parameters do you specify?

## FTTH technical tutorialTechnical considerations - Speed

- Data requirements
- Competition:  ADSL, cable modem ~0.5 to ~1.5 Mb/s shared, asymmetrical
- FTTH ~10 to 30 Mb/s non-shared or several 100 Mb/s shared, symmetrical
- SDTV video takes 2-4 Mb/s today at IP level
- HDTV takes maybe 5 times STDV requirement
- Pictures can run 1 MB compressed
- 5.1 channel streaming audio would run ~380 kb/s

## FTTH technical tutorialTechnical considerations - Speed

## FTTH technical tutorialTechnical considerations – Speed (IPTV Reference)

**Technology**

**Minutes**

**Hours**

**Days**

**Modem 56 **

**kb/s**

**2**

**ISDN 128 **

**kb/s**

**20**

**12**

**DSL 1 Mb/s**

**2.5**

**Cable 2.5 **

**Mb/s**

**1**

**45**

**FTTH **

**0.4**

**Estimated minimum time to acquire **

***Braveheart***

**August 17, 2001:**

**MGM, Paramount Pictures, Sony **

**Pictures, Warner Brothers, and **

**Universal Studios unveiled plans **

**for a joint venture that would **

**allow computer users to **

**download rental copies of feature **

**films over the Internet.**

**December 9, 2002:**

**“****Hollywood's Latest Flop”**

**Fortune Magazine**

***“******The files are huge. At 952 ***

***Megabytes, Braveheart took just ***

***less than five hours to download ***

***using our DSL Line at home... in ***

***the same time we could have ***

***made 20 round trips to our ***

***neighborhood Blockbuster***

**”**

**FTTH technical tutorial*****Technical considerations – Speed (IPTV Reference)***

## FTTH technical tutorialTechnical considerations

- Data is shared in the downstream direction in most systems
- Your Gateway filters out all packets not intended for you
- But there is fear that someone will snoop on your data
- FSAN has a low-complexity, low-security encryption scheme
- 802.3ah has formed a committee to study security
- Manufacturers have taken their own tacks on security, from none to robust

**FTTH technical tutorial*****Technical considerations***

## FTTH technical tutorialData Flow and Security - Downstream

**FTTH technical tutorial*****Data Flow and***** *****Security - Downstream***

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**Tom**

**Dick**

**Harry**

**Box on side of home separates out only the data bound for that subscriber.  But the fear is that someone will fool his box into giving data intended for another subscriber.  Solution is to encrypt the data.**

**Time division multiplex (TDM) – each subscriber’s data gets its turn.**

## FTTH technical tutorialData Flow and Security - Upstream

**FTTH technical tutorial*****Data Flow and***** *****Security - Upstream***

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**Tom**

**Dick**

**Harry**

**Due to the physics of the network, Harry’s data flows upstream but does not come to Tom’s box, so Tom cannot see Harry’s data**

**Time division multiple access (TDMA) – similar to downstream, with gap for laser start/stop**

## FTTH technical tutorialData Flow and QoS

**FTTH technical tutorial*****Data Flow and***** *****QoS***

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**Tom**

**Dick**

**Harry**

**If Dick has paid for more bandwidth, he gets more**

**If Tom’s packets need higher priority (e.g., telephone), they go first**

## FTTH technical tutorialTelephony Considerations

- Depending on whether the FTTH system is based on ATM or Ethernet, the basis of the phone technology is either conventional switched circuit or the newer VoIP

## FTTH technical tutorialConventional Switched-circuit Telephone

## FTTH technical tutorialExample VoIP System

## FTTH technical tutorialVideo

- Video is a popular service, which is a good basis for any new entrant FTTH provider.  There is one way to provide video on cable and satellite (broadcast) and one way to provide video on DSL (IPTV).  There are two ways to provide video on FTTH (broadcast and IPTV).  The market place can sort out the use of each, to the benefit of the subscriber.  We will describe the differences.

## FTTH technical tutorialTechnical considerations - Video

- Broadcast (cable TV standards)
- Analog
- Digital
- Cable TV good engineering practice is 47-48 dB C/N
- FTTH can achieve 48-51 dB C/N
- Benefit from high volume and plethora of applications of cable boxes
- RF return support for STTs
- IPTV – TV transmitted over Internet Protocol
- Feasible, and some people are doing it in place of broadcast
- Bandwidth hog, but statistics can work for you
- Interesting hybrid model awaits hybrid STTs, but can give the best of both worlds

**FTTH technical tutorial*****Technical considerations - Video***

## FTTH technical tutorialWays of transmitting video

## FTTH technical tutorialWays of transmitting video – wave division muxing

## FTTH technical tutorialWays of transmitting video – broadcast headend

## FTTH technical tutorialWays of transmitting video – broadcast subscriber

## FTTH technical tutorialWays of transmitting video – IPTV headend

## FTTH technical tutorialWays of transmitting video – IPTV subscriber

## FTTH technical tutorialWays of transmitting video – IPTV unicast (VOD)

## FTTH technical tutorialWays of transmitting video – IPTV unicast (VOD)

**FTTH technical tutorial*****Ways of transmitting video – IPTV unicast (VOD)***

## FTTH technical tutorialWays of transmitting video – IPTV multicast

## FTTH technical tutorialWays of transmitting video – IPTV multicast

## FTTH technical tutorialPON link budgets

- A system is limited in the distance you can send signals and the maximum number of times you can split the signal to go to different subscribers.  The main problem is usually that the signal level drops too low to be usable.  Other considerations sometimes dominate.

## FTTH technical tutorialPON link budgets

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**Fiber loss per km is 0.25 dB (1550 nm) to 0.4 dB (1260 - 1360 nm)**

**//**

**Every time the signal is split two ways, half the power goes one way and half goes the other.  So each direction gets half the power, or the signal is reduced by**
** ****10log(0.5)=3 dB. **
** ****Practical loss is 3.5 dB nominal, so every two-way split costs about 10 km distance @ 1310 nm**

**Half**

**Half**

## FTTH technical tutorialPON link budgets

- Broadcast analog video often sets the budget
- Maximum practical level without SBS issues ~16 dBm (long spans)
- Minimum receive level for 48 dB C/N ~-5 dBm
- Link budget is ~21 dB, a bit more if you are careful
- At 1550 nm, fiber exhibits loss of about 0.25 dB/km, so maximum distance without amplification is ~80 km
- Requires good externally-modulated transmitters (available)
- Each two-way split results in a loss of nominally ~3.5 dB of level, assume 4 dB worst case.
- Thus, each two-way split costs about 16 km distance

## FTTH technical tutorialAnalog video link budgets

| Split | Nom. splitting loss (dB) | Avail. fiber loss (dB) | Nom. Distance (km) |
| --- | --- | --- | --- |
| 4 | 7 | 11 | 44 |
| 8 | 10.5 | 7.5 | 30 |
| 16 | 14 | 4 | 16 |
| 32 | 17.5 | 2.5 | 10 |
| 64 | 21 | -1 | -4 |

***Notes: based on nominal fiber and splitter loss, not worst case.  Practical distances are less.  Includes 2 dB for connectorization loss, 1550 nm externally modulated transmitter***

## FTTH technical tutorialGigabit EPON link budgets (example, based on GBE best case)

| Split | Nom. splitting loss (dB) | Distance (km), 40 km GBIC | Distance (km), 70 km GBIC |
| --- | --- | --- | --- |
| 4 | 7 | 14 | 44 |
| 8 | 10.5 | 4 | 34 |
| 16* | 14 | - | 24 |
| 32 | 17.5 | - | 14 |
| 64 | 21 | - | 4 |

***Notes: based on nominal fiber and splitter loss, not worst case.  Includes 2 dB for connectorization loss, 1310 nm DFB laser***
**** EFM standard split ratio, 10 and 20 km optics***

**Notes:**
This gives a feel for distances when a high quality DFB laser is used for transmission.  If F-P lasers are used, distances will be less than about 10 km due to dispersion.

## Fiber-to-the-Home (FTTH)Overview and technical tutorial

- The FTTH Council
- FTTH market overview
- FTTH technical tutorial
- Standards update
- Questions

## FTTH technical tutorialStandards?

- Customers want to use standardized systems for maximum choice in equipment, lowest cost, and widespread availability
- There are two known groups working on standards
- FSAN – Full Service Access Network
- Reports submitted to ITU as the standards body
- Formed by 7 telecom companies in 1995
- Now many more members
- G.98x series of standards, most based on ATM but now adding others
- IEEE 802 EFM – Ethernet in the First Mile
- First standards due out 2004
- Fiber and copper Ethernet to the home and business

## FTTH technical tutorial ITU-T G.98x series

- Only published international standard for FTTH
- Describes a Passive Optical Network carrying ATM traffic and TDMA subscriber access
- Several versions published since October 1998
- G.983.1 - Basic ATM-PON system
- G.983.2 - ONT management and control interface
- G.983.3 - WDM system for enhanced services (i.e. analog video)
- G.984.1 and -.2 – GPON (hybrid ATM and Ethernet)
- G.985 – 100 Mb/s point-to-point, Ethernet

## FTTH technical tutorial IEEE 802.3ah - Ethernet in the First Mile (EFM)

- Organized informally via the IEEE 802.3 in Fall 2000
- Chartered as IEEE 802.3ah in Spring 2001
- Develop 1 Gb/s Ethernet access standards including FTTH
- Point-to-Point (home run)
- Point-to-Multipoint (PON)
- Twisted pair standards too
- Publication expected September 2004

## FTTH technical tutorial IEEE 802.3ah EFM status

- PON Physical Medium Dependent (PMD) based on ITU-T 983 series
- Home run PMD based on fast and gigabit Ethernet standards

## Fiber-to-the-Home (FTTH)Overview and technical tutorial

- The FTTH Council
- FTTH market overview
- FTTH technical tutorial
- Standards update
- Questions

## www.ftthcouncil.org