White paper
Background
Changing TV consumer habits and the migration from linear TV to on-demand services (OTT, IPTV or unicast DVB, VoD, catch-up, NPVR, etc.) will drive broadband connectivity speeds to a new level. is is being further accentuated with the emergence of new video formats (HD, Ultra-HD, 3D). A downstream speed of 10Mbps is no longer adequate for a high-quality consumer experi-ence – within the next fi ve years, operators will have to off er guaranteed speeds of at least 30Mbps to each cus-tomer, and even 100Mbps per customer will be normal. e most likely model to deliver these services will be some type of over-the-top delivery – meaning that the back-offi ce service platform will be able to deliver TV con-tent over unmanaged broadband access networks and into retail market consumer devices. e drivers for OTT delivery are as follows:
• Mobile TV services can be off ered – both in-home and while on the go
• e service can be marketed to all consumers – not only to those who are connected via the service provider’s own access network
• e service can be made compatible with various types of end devices
• e creation and management of the service can pre-dominantly be done in the back-offi ce / cloud, with the benefi t of limited software complexity at the end-user device level
For existing linear-TV services, DVB distribution remains the superior technology, due to both superior CAPEX / OPEX benefi ts and also consumer experience (simplicity, zapping-time, elimination of STBs, etc).
erefore, we can make the following list of basic re-quirements for the next generation of access networks:
• DVB distribution for mainstream linear TV services • Guaranteed subscriber line speeds from 30Mbps to
100Mbps and beyond for IP video streaming. Low latency to enable cloud architecture and services such as on-line games
• CAPEX with reasonable payback periods and clear ROI. e investments will preferably be based on a pay-as-you-grow model
• Future-proof topology for the inevitable outside fi bre plant construction
• Streamlined subscriber provisioning and management to reach a low OPEX and fast subscriber help-desk sup-port
• Standard interface between the subscriber modems and access networks, enabling multivendor interoperability and subscriber modem distribution via retail sales chan-nels
Subject to the operator’s business strategies, the follow-ing specifi c requirements may also need consideration: • Analogue TV distribution
• FM radio distribution
• e capability of utilizing the same access network to handle traffi c from several service providers and of even using diff erent broadband access technologies
e required speeds can be achieved with Fiber to the Home (FttH), but the cost of building such networks, par-ticularly within the infrastructure of an existing building, does not give reasonable return on investment. As FttH is simply too expensive in locations other than green fi eld areas, the operators need some other ways to deliver high-speed broadband to their subscribers. e main cost in FttH installations comes from the last ten or hundred metres close to home and inside the building.
Data over Coax – quality service at lower costs
With the growing popularity of OTT video services and high defi nition video formats,
broadband users will need signifi cantly higher bandwidth in the future. Fibre to the Home
would provide suffi
cient speeds, but bringing fi bre connections to people’s homes is far
too expensive in a typical European apartment building.
However, there is a simple solution. Data over Coax (DoC) provides a versatile and
cost-effi
cient alternative for bringing high-speed broadband connections to customers by
using existing coaxial cabling – for under one-fi fth of the price compared to FttH. In this
whitepaper, we discuss Data over Coax’s architecture and the merits of diff erent DoC
technologies.
Just like with plumbing repairs, the cost does not come from the plumbing itself, but from the labour, which is a cost that is diffi cult to reduce.
Being able to exploit existing cabling infrastructures enables the operator to achieve a better return on invest-ment and a faster roll-out of high-speed connections. Recent research suggests that it costs between 2000 and 3000 euros to build a fi bre connection to a single apartment. By using Data over Coax technology, this can be cut down to one-fi fth the cost or less.
e last-mile coax plant is an attractive infrastructure and the quality of the physical medium is undisputed. It is possible already today to deliver the needed speeds over the coax plant, unlike, for example, over a twisted pair network, where such speeds are hard to achieve in real network conditions and with high levels of subscriber penetration.
One key benefi t of a coax plant is its inherent capability to simultaneously deliver both DVB services and broad-band access – and even analogue TV and FM radio.
In this document, diff erent Data over Coax (DoC) tech-nologies are introduced and the main characteristics explained.
Architecture for Data over Coax
e architecture of the proposed access network is rela-tively straightforward. e passive part of a coax plant is used to gain access to individual households. ose coax segments are served by using traditional point-to-point Ethernet technology or some form of Passive Optical Network (PON) technologies.
Even today, there are several DoC technologies that can fulfi l either completely or partly the previously listed requirements and others will be coming to the market in the near future. Probably the best-known DoC technol-ogy is DOCSIS (Data over Coax Service Interface Speci-fi cation); its latest release, DOCSIS 3.0, is already being widely deployed. Other possible technologies include MoCA (Multimedia over Coax Alliance), ITU G.hn and IEEE P1901. All these technologies are briefl y introduced in the following section.
O E Optical Ethernet Access Coax Adaptation
Coax Network
CPEData over Coax technologies
uCMTS / Broadcom CMC
e traditional ideology is that DOCSIS technologies should have a CMTS at the head-end to feed hundreds of cable modems. However, as the dedicated speed per customer is on the rise, the size of each data segment is getting smaller and smaller. With the introduction of Broadcom’s DOCSIS®-based Ethernet over Coax (EoC) technology, it is now possible to move the CMTS from the head-end closer to the customer. is opens up new opportunities for using DOCSIS as the last-mile access solution together with P2P / PON Ethernet trunk net-works.
e main benefi ts of DOCSIS based DoC solutions are as follows:
• Widely adopted, mature standard covering OSI layers 1-3 • Wide selection of subscriber modems in volumes
• Proven to work in a coax network with active equipment; it is also possible to run analogue TV, FM radio and DVB services
• In the case of an operator running a DOCSIS service, the DoC infrastructure would be compatible with existing back-offi ce systems and existing cable modems • In the case of an operator having installed a base of
CMTSs, there can be a gradual evolution to DoC architec-ture with no stranded assets
e main challenges are as follows:
• Unnecessary complexity in the case of a totally passive coax plant with a higher CAPEX / OPEX compared to other DoC alternatives
• A high-quality, two-way-capable coax plant is a pre-requisite
• Current DOCSIS provisioning standard is not compatible with, e.g., GPON
• Only one silicon manufacturer committed to this technol-ogy, which may prevent price erosion
ITU G.hn
ITU G.hn is a next-generation, unifi ed coaxial, phone line and power line home networking standard. Even if the main target for this standard is in-home networks, the same technology can also be used in access networks when the access features are implemented on top of the standard-based solution.
e G.hn power line standard uses frequencies below 100MHz. As the technology is originally meant for power line communication, the robustness and error correction technologies are state of the art. In a coax environment, the expected throughput is approximately 600Mbps (half-duplex), which is shared by the shared. In practice, this means that if 30Mbps per customer is needed, then the system can feed approximately 20 customer connections. CATV G.hn PLC / IEEE P1901 MHz 87 65 (EURO) DOCSIS 3.0 US 1000 108 FM 450 1500 3000 (EURO) DOCSIS 3.0 DS G.hn RF EoC-S100 HPNA 3.1 32 2000 EPoC US MoCA 2.0 EPoC DS 350
DIGITAL FUTURE. Revolution in communication leads to the explosion of digital network content. With such connection numbers, latency is also well under
control.
e G.hn standard also includes the possibility to use high-er frequencies, starting from 450MHz. In networks whhigh-ere the cable TV services are not using the 600 … 860 (1000) MHz area, the use of higher frequencies is a good choice. e G.hn uses 100MHz contiguous frequency blocks with the possibility to notch selected frequencies.
G.hn chipsets are currently available and the access feature fi rmware will be available probably at some point during 2012.
e main benefi ts of the G.hn based DoC solution are as follows:
• Even a lower-quality passive coax plant can typically be used – without needing to make the plant two-way capable
• Makes it possible to also run analogue TV, FM radio and DVB services in the same coax
• ITU-T standards (for layers 1 & 2) exist
• If ITU G.hn becomes the winning standard for home networking, chip-set prices will drop signifi cantly
• DOCSIS can co-exist when high frequencies (450MHz…) are used
e main challenges are as follows:
• Lack of standard covering, also for layer 3, e.g. provisioning • More limited availability of subscriber modems (today) • Does not work in a coax plant with amplifi ers without
special arrangements
• Uses the same frequencies as DOCSIS upstream if power-line frequencies (0…100MHz) are used
IEEE P1901
IEEE P1901 is a similar technology as ITU G.hn. e main diff erence has been that the IEEE only included a power line in a standard network. Now, the IEEE works on P1905.1 (Standard for a Convergent Digital Home Net-work for Heterogeneous Technologies) standard, where other mediums are also included.
e IEEE P1901 uses frequencies of up to 70MHz and delivers approximately 500Mbps (half-duplex) through-put, which is shared by the users. Large volumes of P1901 chipsets are available already today.
As the main players in the P1901/P1905.1 standard are mainly focused on in-home connectivity and not on access solutions, using this technology does not seem feasible.
MoCA 2.0
e Multimedia Over Coax Alliance has ratifi ed a new 2.0 standard in which lower frequencies (starting from 500MHz center frequency) can now be used as well. e use of frequencies over 1GHz has not been successful due to the coax network passive’s behaviour at such high frequencies (attenuation, return loss, isolation). In the 2.0 specifi cation, the expected throughput is approximately 400Mbps, and there is also the possibility to bond two channels together to achieve 800Mbps speeds. Compared to the G.hn, the MoCA is still predominantly a US-based, in-home technology. e standardization is governed by MoCA and there is only one major silicon vendor. e latest developments suggest that MoCA standards will be merged with G.hn or IEEE P1901 / 1905.1 standards.
MoCA 2.0 chipsets are not yet available, but they should be available at some point during 2012. MoCA 1.1 also includes access features, but the availability of the 2.0 access feature fi rmware is still unknown.
e main benefi ts of the MoCA 2.0 based DoC solutions are as follows:
• Even a lower-quality passive coax plant can typically be used – without needing to make the plant two-way capable
• It makes it possible to also run analogue TV, FM radio and DVB services in the same coax
• Good line-speed
• If MoCA 2.0 becomes the winning standard for home networking, chip-set prices will drop signifi cantly e main challenges are as follows:
• Because 2.0 chipsets are not yet available, product im-plementations are coming later than those for compet-ing DoC technologies
• Formal standards are still not mature
• Does not work in a coax plant with amplifi ers without special arrangements
Note: MoCA 1.0 / 1.1 chipsets are available today, but their use is not considered here because it is not feasible to use such high frequencies in coax access networks.
SUMMARY
With the advent of HD and OTT video services, consumers need a very high bandwidth and almost fi bre-level con-nections to their homes. However, in a typical European apartment building, bringing fi bre concon-nections all the way to consumers’ homes is too expensive to be a viable business for operators. e main cost comes from building the connections to individual apartments. is cost can be reduced to one-fi fth the initial cost by bringing fi bre con-nections to an apartment building (FttB) and by utilizing existing coaxial cables to connect individual apartments. e new Data over Coax technologies enable operators to bring fi bre-level connection speeds to consumers by utilizing existing cabling – for one-fi fth the price. DoC technologies off er attractive options for building professional, standard-based, next generation FTTB networks. e base technologies exist already today or will be coming in the immediate future.
When out-of-band technologies are considered, G.hn and MoCA (2.0) are the main technologies. Choosing between these two technologies depends mainly on the quality of the coax access plant. Another key factor is the volume market adaptation of these technologies.
e Broadcom DOCSIS®-based Ethernet over Coax (EoC), also known as CMC (Coax Media Converter), is an inter-esting concept when in-band communication can be used. is technology can be more fl exibly deployed because it is designed to operate in existing quality HFC networks. e massive volume CPE availability makes the launch of the technology straightforward.
Teleste has been a pioneer in the fi eld of Data over Coax technologies. First-generation products and fi eld deploy-ments were launched in 2006. We are now engaged in evaluation and fi eld tests with 2nd generation chipsets that off er greatly improved performance as well as solid standards. Teleste is in a unique position to innovate in this fi eld due to our intimate knowledge of the HFC infrastructure as well as IP networking. Additionally, Teleste can off er these technologies as a “Build – Operate – Transfer” solution with our fi eld force of optical and coax network professionals.
Teleste is an international technology group founded in 1954, which is specialised in broadband video and data
communication systems and services. e group is active in two business segments, Video and Broadband Solutions and Network Services; in both fi elds, we are among the global leaders. Video is at the core of our business activities, with a focus on the processing, transmission and management of video and data for operators and public authori-ties. In 2011 the group’s net sales totalled almost EUR 184 million. e company has nearly 30 offi ces world-wide and over 90% of Teleste’s net sales are generated outside Finland. e company is listed on the NASDAQ OMX Helsinki Ltd. Visit www.teleste.com for more information.
Teleste Corporation
P.O.Box: 323, FI-20101 Turku, Finland Phone: +358 2 2605 611 Fax: +358 2 2446 928 [email protected] www.teleste.com
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