A-bard Wired Technologies

Technology Report 3: Wired broadband solutions for rural Europe

December 2005

09/01/06

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Technology Report 3: Wired Broadband solutions for rural Europe

Introduction While telecommunications started from deploying isolated links that directly connect two points, and developed through the stages of isolated islands

and

networks

dedicated

to

certain

applications,

the

telecommunications environment of today should rather be viewed as an integrated global network. It may unite a number of different transport technologies to cooperate for serving an individual application, as well as let multiple applications share common transport networks. The latter fact significantly changes the way in which building of networks should be approached today. From a deep engineering task, usually resulting in development of proprietary systems, the accent is being shifted to integration of all kinds of standardised technologies. This trend is especially intensified by digitalisation of services, which makes everything moving towards what would be looking more like universal data networking. Two aspects of viewing the networks should be clearly understood and distinguished: •

Technology. This is the engineering part. It includes all kinds of hardware a software means that provide physical media along with the due access techniques, modulation and transmission of information between endpoints, interfaces letting applications to access services.

•

Operation. This deals with integrating and selling end-to-end services

to

the

ultimate

users.

Network

operators

use

technologies that they own themselves or lease from somebody else, as well as cooperate with other operators, to ultimately get their users either connected between them or having access to the needed resources.

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Technology Report 3: Wired Broadband solutions for rural Europe

Physical media The purpose of the physical layer is to transport a raw bit stream from one machine to another. Various physical media can be used for the actual transmission. Each one has its own niche in terms of bandwidth, delay, cost, and ease of installation and maintenance. Media are roughly grouped into guided media, such as copper wire and fiber optics, and unguided media, such as radio and lasers through the air.

Cooper Copper wire has been used for many years as the mainstay of signal transmission. It has low electrical resistance, so the loss due to current flowing in the wires is quite small. It is very easy to work; it can be bent and straightened many times without breaking, i.e. it is malleable. Copper wire cable used in telecommunications comes in two varieties: •

Twisted pair - Twisted pair data cables for LANs are specified as categories 3, 4, 5, 6 or 7. Most used is CAT-5, specified by standards TIA/EIA 568A,

ISO/IEC 11801, EN 50173. •

Coaxial pair - The 75-ohm cable is commonly used for analogue transmission, including cable TV networks.

•

The 50-ohm cable is commonly used in data networks.

Fiber Fiber optics, compared to copper wires, is a relatively new technology. The fiber optic cables are more expensive in production and maintenance, but they offer significantly more bandwidth,

hence

higher

transmission speeds. Several varieties of optic cables exist December 2005

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Technology Report 3: Wired Broadband solutions for rural Europe

today, having different properties.

Hybrid Fiber Coax (HFC) system The HFC network is a broadband access network comprising an opticalfiber part from the head end location to optical network units (ONUs), which serve the customers via coaxial cable. HFC was developed for expanding the service selection over the existing coaxial cable infrastructure originally used for CATV

(Cable

TV)

service

provision only. Consequently earlier networks were limited to analogue video distribution. Nevertheless

new

HFC

systems

support

both

may

broadcast

and

interactive

services,

depending

on

the

system architecture. They might be able to deliver full range of analogue and digital services: telephony services (cablephone), audio and video distribution, video-ondemand and high bit rate data services (cable modem) e.g. high speed Internet access on the same network. HFC supports a mix of analogue and digital channels using a frequencydivision multiplexing (FDM) scheme. The available bandwidth is split into channels: the downstream traffic contains analogue distribution channels, digital channels for video and audio distribution, and video-on-demand, and finally for the downstream part of interactive services. The upstream traffic contains digital channels for interactive services. Due to the FDM approach, HFC provides an evolutionary path for the analogue to digital transition and from distribution to interactive services.

Wave Division Multiplexing Wave Division Multiplexing (WDM and DWDM) is a multiplexing technology that divides the optical beam on a single fiber strand into its component colours (wavelengths). Standard means of increasing the number of wavelength channels involve the use of narrower channel spacing or optical amplification. Due to the increasing complexity of providing a large number of wavelengths, current research is focusing on December 2005

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Technology Report 3: Wired Broadband solutions for rural Europe

raising the total aggregate capacity carried over a fiber strand. Vendors are increasing wavelength channel rates from 2.5 Gbps to 10 Gbps, 20 Gbps and up to 40 Gbps. Each wavelength can be made to carry as much (or more) information than previously passed through the entire fiber strand. One of the main attractions of DWDM is that it can be installed on existing in ground fiber without digging it up - meaning lower installation costs for additional capacity. This is already having an impact on the cost of longhaul transport in Australia, but has yet to make a dent in last mile connectivity, largely due to the costly requirement of laying fiber in the first place.

Electric power line communications Power line communications (PLC) means data transfer via a combination of the power network within the home or office and the metropolitan power distribution grid. Instead of having to install dedicated cabling, PLC uses power lines to carry data. signals and electricity are combined together and, once in the home, all power sockets can be

used

to

connect

to

the

data

communications. BPL (Broadband over Power Line) These systems operate on an unlicensed basis. BPL systems may operate either inside a building (“In-house BPL”) or over utility poles and medium voltage electric power lines (“Access BPL”). As In-house BPL systems can use the electrical outlets available in every room of a building to transfer information between computers and between other home electronic devices, they eliminate the need to install new wires between these devices. Access BPL systems can be used to provide high speed internet access and other broadband services to homes as well as providing electric utility December 2005

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Technology Report 3: Wired Broadband solutions for rural Europe

companies with a means to more effectively manage their electric power distribution operations. Access BPL can be made available in conjunction with the delivery of electric power, it may provide an effective means for last mile delivery of broadband services, and may offer a competitive alternative to digital subscriber line (DSL), cable modem services and other high-speed Internet technologies. BPL is standardised in: ETSI-PLT

Potential for interference Some groups oppose the proliferation of this technology, mostly due to its potential to interfere with radio transmissions. As power lines are typically untwisted and unshielded, they are essentially large antennas, and will broadcast large amounts of radio energy. Recently, power and telecommunications companies have started tests of the BPL technology, over the protests of the radio groups. Interference free PLC G-line technology It now appears there is a technology that will provide faster data rates (demonstrated up to 216 Mbps) than the systems operating in the 1.7 to 80 MHz range, and also eliminate interference to HF operations. The system, developed by Corridor systems-USA, uses microwave spectrum instead of HF frequencies. This new technology can leverage existing low-cost 802.11 chipsets, achieving lower cost than competing PLC solutions. Corridor Systems’ technology uses the spectrum between 2 GHz and 20 GHz, avoiding the HF and VHF frequencies entirely. Recently, Corridor Systems has tested and demonstrated simultaneous operation of its PLC technology and amateur radio HF communications. Utilizing a 100 watt, 7 MHz, 21 MHz and 28 MHz amateur SSB/CW transmitter connected to a dipole antenna located within 20 feet of an operating PLC system, there was not any evidence whatsoever of the operation of one system in the other. Amateur UHF communications at 446 MHz and at a 25-watt power level were similarly unaffected and in turn were not detected by the PLC system. Examination of the 0.1–30 MHz HF spectrum with a quality communications receiver also revealed no evidence of the PLC system.

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Technology Report 3: Wired Broadband solutions for rural Europe

Hybrid Fiber Radio (HFR) The integration of wireless and optical networks is a potential solution for increasing capacity and mobility as well as decreasing costs in the access network. By use Hybrid Fiber Radio (HFR), the capacity of optical networks can be combined with the flexibility and mobility of wireless access networks. An exciting possibility is to reduce the complexity, and thereby the cost, at the radio transceiver sites. By using HFR, a large part of the complexity can be transferred to a central office deeper into the network. With this approach, one can also steer the radio capacity to where it is mostly needed and it also offers ways to centralise and simplify mobility handling. The overall purpose of the project is to evaluate how integrated wireless/optical access networks may be implemented several years from now in the future. This timeframe enables us to consider some quite promising state-of-the-art technologies and also how today’s HFR technologies can be incorporated in the access networks. In this document technical results are presented and architectures for wirelessoptical access networks are proposed. The document starts with an overview of today’s wireless - and fixed access networks, in order to give some background. After this a description of the technical requirements on the HFR technologies are discussed. Thereafter, different HFR technologies are described in some detail and results from dynamic range measurements of electro absorption modulators are presented. In the next section, the wireless-fixed AM convergence is analysed, especially how HFR can play a role and it is also described how HFR can be used to enhance mobility in the access network. Finally, in the last chapter, architectures for wireless-optical access networks are proposed. The parameters of the different wireless access networks put requirements on the HFR technology. The most important parameters are RF and IF frequency, output power (ERP) and Dynamic Range (DR). Both the output power and the dynamic range are dependent on the environment and cell size and on the radio system itself.

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Technology Report 3: Wired Broadband solutions for rural Europe

Last mile A passive optical network (PON) is a system that brings optical fiber cabling and signals all or most of the way to the end user in residential and new small/medium business networks. Depending on where the PON terminates, the system can be described as fiber-to-the-curb (FTTC), fiber-to-the-building

(FTTB),

Fiber To The Cabinet (FTTCab), Fiber To The Office (FTTO) or fiber-to-the-home Passive

Optical

(FTTH). Networks

(PONs) utilize light of different colours

(wavelengths)

over

strands of glass (optical fibers) to transmit

large

amounts

of

information between customers and network/service providers. The passive simply describes the fact that optical transmission has no power requirements or active electronic devices once the signal is going through the network. With PONs, signals are carried by lasers and sent to their appropriate destination by devices that act like highway interchanges, without the use of any electrical power, eliminating expensive powered equipment between the provider and the customer. PONs offer customers video applications, high-speed Internet access, multimedia and other high-bandwidth capabilities Fiber to the Curb Fiber optics provide the highest level of network performance. However, to deliver services to an end customer, the broadband signal must be converted from optical to electrical at some point in the network. At the conversion point, the physical cable changes from fiber to copper. While fiber optic costs are coming down, there is still significant expense involved, including the requirement for customer premise equipment (optical electrical converters). Alternatively, if the optical electrical converters are placed at or near the end of the backbone network, the last mile of the customer access network can be provided via copper wire. Hybrid fiber/copper architecture involves the deployment of fiber optic cables that terminate at an ONU (Optical Network termination Unit). At the ONU, the signal is transferred from the fiber to the final copper drop to December 2005

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Technology Report 3: Wired Broadband solutions for rural Europe

the subscriber or user. This is known as a Fiber to the Curb (FTTC) topology. In FTTC architectures, last mile connectivity is generally provided via VDSL (Very high-speed DSL) or copper coaxial cable. VDSL was originally developed as part of the Telco Fiber to the Curb (FTTC) topology. Because VDSL gains in speed but loses in distance or range, there is a need for a high capacity feed to bring the service to within 2 km of the user. The feed is a fiber optic link terminating in an ONU (Optical Network termination Unit). The FTTC/HFC (Fiber to the Curb/Hybrid Fiber Coax) architecture is similar in structure to FTTC/VDSL. From the headend, content travels over a fiber link, or trunk, to an Optical Network Unit (ONU) / Optical Node / Fiber Node serving a particular neighbourhood. The ONU, or node, converts the optical transmission into an RF signal that is then distributed over a set of coaxial feeder cables, or branches, to the neighbourhood. In each neighbourhood, a set of taps is used to splice into the feeder cable to connect a drop cable between the pole and the home. HFC channels can support up to 38 Mbps downstream and 10 Mbps upstream. However, this bandwidth is generally shared between subscribers. Typical access speeds experienced by cable modem subscribers' range from 500 Kbps to 1.5 Mbps - depending on network architecture and traffic load. The major difference between the FTTC/VDSL and FTTC/HFC architectures can be summarised as the difference between shared and dedicated bandwidth. With VDSL every copper wire (subscriber connection) can carry up to 52 Mbps downstream. With HFC, every channel on the coax cable can carry up to 38 Mbps downstream. All subscribers serviced by an Optical Node (eg. The neighbourhood node) share the same channel capacity. Additional capacity can be allocated to individual neighbourhoods via the use of multiple channels for data. A twist on the standard FTTC/HFC model occurs when the cable plant conforms

to

the

DOCSIS

(Data

over

Cable

Service

Interface

Specification) standard. Under DOCSIS, each cable user is allocated a pre-defined upstream/downstream bandwidth. For instance, subscribers may be allocated a 64 Kbps upstream and 256 Kbps downstream portion of a cable channel.

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Technology Report 3: Wired Broadband solutions for rural Europe

Fiber In The Home Fiber to the home (FTTH) is the ideal fiber-optics architecture. In this architecture, fiber deployment is carried all the way to the customer’s home (premises}. FTTH has been developed in response to several residential access market drivers, including the following: •

The Internet explosion, second line growth, the desire for higher speeds, alternative strategies such as voice over DSL (VoDSL), voice over IP (VoIP), voice over ATM (VoATM), and cable modems

•

The increased competition in the market due to the growing number of competitive local-exchange carriers (CLECs), an increase in services offered by application service providers (ASPs), •

The Fiber to the Home (FTTH) Council Europe calls on European regulators

to

reconsider

the

European Regulatory Framework, saying that the current rules do not allow national regulators to remove uncertainties surrounding investments in 'deep' fiber deployment. •

It is commonly assumed that optical fiber will migrate deeper into broadband access networks, supporting the rollout of higher speed and symmetrical broadband services. All DSL technologies are hampered by a trade-off between copper line-length and speed. Shortening line lengths, by placing fiber closer to homes, is advantageous for any broadband deployment capable of supporting 'high-definition video' as the Commission's i-2010 strategy requires.

•

Turn-up complexities that affect ease of deployment and maintenance

•

The declining costs of optical equipment

•

Technology life cycles that dictate a need to deploy the right technology at the right time and to future-proof existing networks

Fiber In The Loop Fiber In The Loop (FITL) is a system implementing or upgrading portions of the POTS local loop with fiber optic technology from the central office December 2005

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Technology Report 3: Wired Broadband solutions for rural Europe

of a telephone carrier to a remote Serving Area Interface (SAI) located in a neighbourhood 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 includes various architectures, such as fiber to the curb (FTTC), fiber to the home (FTTH) and fiber to the premises (FTTP). A similar network called a hybrid fiber coaxial (HFC) network is used by cable television operators but is usually not synonymous with "fiber In the loop", although similar advanced services are provided by the HFC network.

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Technology Report 3: Wired Broadband solutions for rural Europe

Fiber To The Cabinet FTTx network architecture (FTTCab – Fiber to the cabinet, FTTH – Fiber to the home) is based on ATM Passive Optical Networks (ATM-PONs, APONs). The FSAN recommended drop technology is VDSL over copper pairs, where available. However, this does not preclude the use of other drop technologies and broadband radio represents an attractive option. Its use would allow the fast deployment of services where a wired access network is not readily available thus providing added flexibility. Furthermore, broadband radio has the advantage of low installation cost. The integration of the two technologies is expected to result in an access network with media independent services. This would provide added flexibility to network operators enabling them to deploy the most suitable and efficient technology for each sevice and reduce overall provisioning time. Fiber has much higher capacity than copper - even copper aided by DSL - and can therefore offer very fast downloads

Examples Rowanet ROWANet (rowan is one of Vysocina symbols) is based on optic fibers and by CWDM (multiplex) technology. ROWANet project was prepared for a 1 year period and we tried to find best way to create such an extensive project. It was build on an experience from creating Jihlava city metropolitan network (Jihlava city is a capital of the Vysocina region), which has interconnected 22 public organizations established by the region (schools, hospital, ambulance service, museum, gallery etc.), but ROWANet was projected as a network of 150 km optic fibers, which goes through 7 big towns and 3 villages. The idea is again to interconnect public

administration

subjects

and

organizations established by the region and

to

bring

them

cheaper

telecommunication and data services. As there is possibility for the private telecommunication operators to own a part of the optic cable (on which ROWANet operates) they are able to come to the underdeveloped areas to offer their services. December 2005

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Technology Report 3: Wired Broadband solutions for rural Europe

Anyway, ROWANet has indirect influence on the quality of services for citizens (cheaper Internet connection) and on telecommunication market and competition as well. ROWANet is first ICT project manag d by ICT department of the Vysocina Regional Authority, which is partially financed by region, national budget and ERDF sources. Within the project we also create 10 public Internet access points (Wi-Fi hot-spots) for citizens, which will be placed in every municipality connected to ROWANet. The project deadline was fixed by January 2006. Brithish Telecom To Trial 'Fiber To The Cabinet' BT are to start trials later this month, which will see BT installing its DSLAM kit in street cabinets nearer to homes and businesses. Bringing BT's broadband kit (DSLAMs) closer to end users, it will help deliver broadband to pockets of the UK who are too far away from their local exchanges to currently receive DSL. 0.2% of the country are unable to get DSL broadband (about 100,000 households). These trials will help BT assess the technicalities, performance and cost of this strategy before rolling-out to other areas. Broadband have-nots in Northern Ireland and Yorkshire are to take part in trials designed to wire-up parts of the UK currently without DSL. Five sites in Northern Ireland and four in Yorkshire will take par in the trials. The trials are set to run through until the summer of 2006. BT will install their DSLAM equipment installed in a street cabinet. This DSLAM will then be connected back to the exchange using fiber optic cable.. The lucky areas to be involved in the trial are: Yorkshire:

Barnsley,

Catcliffe,

Doncaster,

Great

Houghton

and

Dodworth, Wheatley Hill and Intake, Treeton and Brinsworth in Rotherham. Northern Ireland: Larne, the Annaghmore area of Portadown, Glenavy area Crumlin, County Antrim, Greencastle area, Gortin, County Tyrone, and the Balmoral area of Belfast. Beginning in December, BT will also start separate trials near Dorchester, Dorset, and in the Kingswells area of Aberdeen.

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Technology Report 3: Wired Broadband solutions for rural Europe

Västerbotten Västerbotten is in the northern part of Sweden. It covers 66,500 square kilometers and has 256,000 people. They have a regional network called AC Net that has 50,000 users so far. There is a 1 Gbps backbone and it is one of 22 European pilot regions within the RISI programme. Needless to say, Västerbotten isn’t exactly a target market for service providers until the municipality put the network in place and in essence, “aggregated” demand. Today every community in Västerbotten has access to the fiber network. A homeowner who wants a fiber connection has to pay a one-time installation fee of 2000 SKr (€ 212 or $255) to cover equipment plus labor, and a 250 SKr (€ 27 or $32) monthly fee. The homeowner can deduct the installation fee on his tax return. Much of the fiber to the home deployments in sparsely populated areas in Sweden are done by the local energy utility, which is owned by the municipality. Although many fiber projects are supported by public funds, there are strict rules imposed by the European Union governing the use of the publicly funded networks. Access has to be wholesaled to commercial service providers on an open, non-discriminatory basis. This guarantees that there will be private companies participating in the exploitation of the network and also ensures that there is competition. At the Brussels seminar, the city and utility representatives told us that they did not want to become service providers to the end user and that in many instances, had pulled out of the business when more private companies began delivering access to residents and businesses. Their goal is simply to deploy an open network and seed the market. This seems to be the preferred public-private partnership model in Sweden, in large part because of strict EU rules governing the use of public funds for broadband infrastructure. So with this in mind - a sparsely populated country with lots of water and islands - you would think the Swedes would be making all kinds of silly excuses not to make Municipalities (and the national government) have been trying to break open the local loop by enforcing open procurement procedures and pushing for more operator-neutral networks. It seems to be working in Sweden.

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Technology Report 3: Wired Broadband solutions for rural Europe

Power line trial The Power Line Trial (PLT) project offers an opportunity to establish affordable broadband communications in areas not able to receive conventional telephone line or cable broadband services. The trial aims to demonstrate the commercial potential of Digital Subscriber Line (DSL) and PLT technology to deliver broadband to rural communities. Current cable and telephone networks do not extend into rural areas, and are unlikely to in the future, as the cost involved would be huge. By sending information using the electricity network, which has almost 100 per cent coverage of the UK population, Internet Service Providers (ISP's) would be able to offer affordable broadband services to all areas of the UK. As part of the PLT project, trials are taking place in Crieff and Campbeltown.

Crieff's trial is being run by SSE Telecom (the

telecommunications division of Scottish and Southern Energy plc), in partnership with Perth and Kinross Council and Scottish Enterprise Tayside. In Campbeltown, SSE Telecom is partnering with Highlands and Islands Enterprise. In Crieff a PLT network has been built to provide broadband ISP services and direct connections to users. Broadband Internet is initially being delivered to 13 sub-stations using conventional DSL technology. From these sub-stations, PLT technology is used for the 'last mile' to the user's building. A PLT access box is fitted in the user’s premises. This is connected to the incoming power supply by a 13-amp plug, and to the network device or PC by a standard network cable. This means that Internet access is brought to the customer through a normal power socket, without the need to tie up an existing phone line or install a new one.

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Technology Report 3: Wired Broadband solutions for rural Europe

Useful links: EUROSCOM

Eurescom is the leading organisation for collaborative R&D

in

telecommunications.

We

provide

efficient

management of research projects and programmes for member companies and other clients. Companies who wish to collaborate on the key issues facing the telecoms industry are welcome to join the Eurescom community. http://www.eurescom.de/ FTTH Council The Fiber-to-the-Home (FTTH) Council Europe is a Europe

market development organization whose mission is to educate, promote, and accelerate the deployment of fiber in access and the resulting quality-of-life enhancements. http://www.europeftthcouncil.com/

Scottish

Scottish

Enterprise

is

Scotland's

main

economic

Enterprise

development agency, funded by the Scottish Executive. Our mission is to help the people and businesses of Scotland succeed. In doing so, we aim to build a worldclass economy \ http://www.scottish-enterprise.com/

Region

http://extranet.krvysocina.cz/jazykoveverze/uk/index.php?

Vysocina

stranka=regadmin.htm

Naturnet

New Education and Decision Support Model for Active

Redime

Behaviour

in

Sustainable

Development

Based

on

Innovative Web Services and Qualitative Reasoning www.naturnet.org Rural Wings

The EU-backed Rural Wings project is using satellite technology to reach schools in remote communities on three continents and provide them with high-speed internet access. http://europa.eu.int/comm/research/headlines/news/article _04_12_15_en.html

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Technology Report 3: Wired Broadband solutions for rural Europe

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