White paper Data over Coax
Data over Coax quality service at lower costs With the growing popularity of OTT video services and high definition video formats, broadband users will need significantly higher bandwidth in the future. Fibre to the Home would provide sufficient speeds, but bringing fibre 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 costefficient alternative for bringing high-speed broadband connections to customers by using existing coaxial cabling for under one-fifth of the price compared to FttH. In this whitepaper, we discuss Data over Coax s architecture and the merits of different DoC technologies. 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. This 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 experience within the next five years, operators will have to offer guaranteed speeds of at least 30Mbps to each customer, and even 100Mbps per customer will be normal. The most likely model to deliver these services will be some type of over-the-top delivery meaning that the back-office service platform will be able to deliver TV content over unmanaged broadband access networks and into retail market consumer devices. The drivers for OTT delivery are as follows: Mobile TV services can be offered both in-home and while on the go The service can be marketed to all consumers not only to those who are connected via the service provider s own access network The service can be made compatible with various types of end devices The creation and management of the service can predominantly be done in the back-office / cloud, with the benefit 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 benefits and also consumer experience (simplicity, zapping-time, elimination of STBs, etc). Therefore, we can make the following list of basic requirements 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. The investments will preferably be based on a pay-asyou-grow model Future-proof topology for the inevitable outside fibre plant construction Streamlined subscriber provisioning and management to reach a low OPEX and fast subscriber help-desk support Standard interface between the subscriber modems and access networks, enabling multivendor interoperability and subscriber modem distribution via retail sales channels Subject to the operator s business strategies, the following specific requirements may also need consideration: Analogue TV distribution FM radio distribution The capability of utilizing the same access network to handle traffic from several service providers and of even using different broadband access technologies The required speeds can be achieved with Fiber to the Home (FttH), but the cost of building such networks, particularly 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 field areas, the operators need some other ways to deliver high-speed broadband to their subscribers. The main cost in FttH installations comes from the last ten or hundred metres close to home and inside the building.
Just like with plumbing repairs, the cost does not come from the plumbing itself, but from the labour, which is a cost that is difficult to reduce. In this document, different Data over Coax (DoC) technologies are introduced and the main characteristics explained. Being able to exploit existing cabling infrastructures enables the operator to achieve a better return on investment and a faster roll-out of high-speed connections. Recent research suggests that it costs between 2000 and 3000 euros to build a fibre connection to a single apartment. By using Data over Coax technology, this can be cut down to one-fifth the cost or less. The 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 benefit of a coax plant is its inherent capability to simultaneously deliver both DVB services and broadband access and even analogue TV and FM radio. Architecture for Data over Coax The architecture of the proposed access network is relatively straightforward. The passive part of a coax plant is used to gain access to individual households. Those 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 fulfil 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 technology is DOCSIS (Data over Coax Service Interface Specification); 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 briefly introduced in the following section. CPE Optical Ethernet Access O E Coax Adaptation Coax Network Simplified optical access and Data over Coax architecture
Different Data over Coax bandplans FM G.hn PLC / IEEE P1901 (EURO) DOCSIS 3.0 US CATV (EURO) DOCSIS 3.0 DS G.hn RF HPNA 3.1 EoC-S100 EPoC US MoCA 2.0 EPoC DS 32 65 87 108 350 450 1000 1500 2000 3000 MHz Data over Coax technologies ucmts / Broadcom CMC The 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. This opens up new opportunities for using DOCSIS as the last-mile access solution together with P2P / PON Ethernet trunk networks. The main benefits 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-office 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 architecture with no stranded assets The 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 prerequisite Current DOCSIS provisioning standard is not compatible with, e.g., GPON Only one silicon manufacturer committed to this technology, which may prevent price erosion ITU G.hn ITU G.hn is a next-generation, unified 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. The 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 (halfduplex), 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.
With such connection numbers, latency is also well under control. The G.hn standard also includes the possibility to use higher frequencies, starting from 450MHz. In networks where the cable TV services are not using the 600 860 (1000) MHz area, the use of higher frequencies is a good choice. The G.hn uses 100MHz contiguous frequency blocks with the possibility to notch selected frequencies. G.hn chipsets are currently available and the access feature firmware will be available probably at some point during 2012. The main benefits 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 significantly DOCSIS can co-exist when high frequencies (450MHz ) are used The 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 amplifiers 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. The main difference 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 Network for Heterogeneous Technologies) standard, where other mediums are also included. The IEEE P1901 uses frequencies of up to 70MHz and delivers approximately 500Mbps (half-duplex) throughput, 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. DIGITAL FUTURE. Revolution in communication leads to the explosion of digital network content.
MoCA 2.0 The Multimedia Over Coax Alliance has ratified a new 2.0 standard in which lower frequencies (starting from 500MHz center frequency) can now be used as well. The 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 specification, 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. The standardization is governed by MoCA and there is only one major silicon vendor. The 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 firmware is still unknown. The main benefits 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 significantly The main challenges are as follows: Because 2.0 chipsets are not yet available, product implementations are coming later than those for competing DoC technologies Formal standards are still not mature Does not work in a coax plant with amplifiers 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 fibre-level connections to their homes. However, in a typical European apartment building, bringing fibre connections all the way to consumers homes is too expensive to be a viable business for operators. The main cost comes from building the connections to individual apartments. This cost can be reduced to one-fifth the initial cost by bringing fibre connections to an apartment building (FttB) and by utilizing existing coaxial cables to connect individual apartments. The new Data over Coax technologies enable operators to bring fibre-level connection speeds to consumers by utilizing existing cabling for one-fifth the price. DoC technologies offer attractive options for building professional, standard-based, next generation FTTB networks. The 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. The Broadcom DOCSIS -based Ethernet over Coax (EoC), also known as CMC (Coax Media Converter), is an interesting concept when in-band communication can be used. This technology can be more flexibly deployed because it is designed to operate in existing quality HFC networks. The massive volume CPE availability makes the launch of the technology straightforward. Teleste has been a pioneer in the field of Data over Coax technologies. First-generation products and field deployments were launched in 2006. We are now engaged in evaluation and field tests with 2nd generation chipsets that offer greatly improved performance as well as solid standards. Teleste is in a unique position to innovate in this field due to our intimate knowledge of the HFC infrastructure as well as IP networking. Additionally, Teleste can offer these technologies as a Build Operate Transfer solution with our field 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. The group is active in two business segments, Video and Broadband Solutions and Network Services; in both fields, 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 authorities. In 2011 the group s net sales totalled almost EUR 184 million. The company has nearly 30 offices world-wide and over 90% of Teleste s net sales are generated outside Finland. The 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 video.headends@teleste.com www.teleste.com P3I_Data over Coax Copyright 2012 Teleste Corporation. All rights reserved. TELESTE is a registered trademark of Teleste orporation.