BROADBAND DSL ACHIEVING HEALTHY GROWTH

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1 MEDEA+ News 28 October 2003 BROADBAND DSL ACHIEVING HEALTHY GROWTH There were more than 10 million new subscribers to broadband digital subscriber line (DSL) connections in the first half of 2003, according to figures just released by DSL Forum, the international consortium of leading broadband DSL service providers and equipment manufacturers. This brings the total number of subscribers worldwide to 46.7 million well ahead of the alternative cable modem market. According to London-based industry analyst Point Topic, DSL is the leading broadband technology with 56.5% of the world s mass-market broadband subscribers, followed by cable modems at 38%. Expectations are that global figures will reach 60 million DSL subscribers by the end of While most subscribers around the world currently have asymmetric DSL connections, an increasing number of businesses are using symmetric high rate DSL (SHDSL); and very high bit rate DSL (VDSL) is now being rolled out to support bandwidth hungry applications such as video-on-demand. More than half of the countries showing the greatest subscriber growth and half the top 20 for DSL are in Western Europe. Overall, this region showed the greatest growth for the first two quarters, with 12.8 million homes and businesses now using broadband DSL, second only to Asia-Pacific at 17.8 million subscribers. The US growth rate for the same six months was the third largest globally despite the continuing dominance of broadband cable connections in North America. New technical standards from ADSL2, accepted by the International Telecommunications Union (ITU) in mid 2002, and ADSL2+, accepted in early 2003, to synchronous high bit rate DSL (G.SHDSL) and even faster VDSL are intended both to increase speed and widen the geographical area being served. The DSL Forum has set a target for a global mass market for broadband DSL of 200 million subscribers 20% of all phone lines by the end of South Korea remains the only country in the world to have achieved mass-market status with 29.7% of its phone lines delivering DSL services using a combination of ADSL and VDSL. A further seven countries including Belgium, Denmark, Iceland and Israel have achieved in excess of 10% phone line penetration. Page 1 of 5

2 Seven of the 54 countries that have commercial broadband DSL services accounted for almost 75% of global subscriber growth: Japan added 2.6 million connections; China and the USA each added in excess of one million, and four European countries France, Germany, Italy and the UK added more than half a million new subscribers each. With a 94.1% increase, the UK was the fastest growing country in Western Europe, achieving its first million subscribers to DSL services by mid IP-centric architecture evolution is seen as central to developing protocols necessary for quality of service for IP-delivered offerings, according to the DSL Forum. This work should ensure that DSL provides a solid platform for advanced services. Together with DSL Forum work on interoperability and network management, this should lead to accelerated market growth. In parallel, the DSL Forum continues to promote the benefits of broadband DSL for all end-user groups, through initiatives such as DSLHome, which is focused on educating users on how best to apply their DSL connection for a networked home. From the beginning of MEDEA+, maximum support has been given to developing network, exchange and consumer premises equipment to build a powerful European presence in the global xdsl market. Work includes the already completed MEDEA+ A106 INCA project, which has developed new physical layer components and complete system-on-chip (SoC) designs for highly integrated, low-power xdsl devices. Much emphasis was placed on defining common systems and architecture for future VDSL chipset interoperability. Project partners also contributed to the development of the VDSL standard. The MEDEA+ A103 UniAccess project set out to provide a cost-effective single chip integrated access device providing home gateways for Internet access and supporting equipment from simple telephones to wireless web terminals. It is focusing on open architecture for the whole access network chain with the intention of seeking a new standard for this area. In addition to optimising overall system architecture, the project is defining DSL access multiplexer (DSLAM) functionality and designing standardised DSLAM hardware using standardised buses, connectors and logic interfaces in a similar manner to a PC for high-speed DSL Internet access. The focus on broadband DSL access is continuing in the new batch of MEDEA+ projects announced in 2003, with actions such as the MEDEA+ A110 MIDAS project. This is specifying and developing single chip multistandard integrated access devices for broadband DSL as well as power-line communications for inhome networking. Page 2 of 5

3 Article COMMUNICATING FASTER AND MORE WIDELY Broadband asynchronous digital subscriber line (ADSL) technology currently offers data transfer speeds of up to 8 Mbit/s downstream and 1 Mbit/s upstream. Such high transmission speeds are considered crucial to Internet applications such as interactive multimedia. While integrated service digital network (ISDN) lines should prevail for the next few years, so-called xdsl covering ADSL and higher speed DSL technologies is expected to become the most popular method for high-speed Internet access. The main advantage of xdsl technologies is to allow reuse of existing copper telephone cables for highspeed digital connections, avoiding the need to install new cabling. This allows traditional local voice network operators to offer high-speed Internet connections, and compete with the alternative technologies such as cable modems and both wireless and satellite Internet access. Other benefits of DSL include always-on connections, ease of use, reliability, good security as it offers point-to-point connections from the user to the exchange, and proven technology. Making yourself at home Broadband DSL has come a long way in a little over three years. Initial data rates and geographical reach of asynchronous DSL (ADSL) were relatively low. However, ratification of the new ADSL2 standard in 2002 and now ADSL2+ earlier this year will boost speeds or, more importantly, increase the distances possible between subscriber and exchange, encouraging more mass-market home use. Wider geographical reach is crucial in improving coverage of rural areas. ADSL2 boosts reach from the exchange to 6 km, equivalent to a 20% increase in coverage. The main improvements include: Minimum 8 Mbit/s downstream transfer rate, scalable to a maximum of 15 Mbit/s and a minimum 800 kbit/s upstream rate, scalable to 1.5 Mbit/s; Loop diagnostic tools; Improved initialisation and faster start up; On-line reconfiguration and power management; Framing with up to four frame bearers and up to four latency paths; An optional all-digital model, making use of the voice bandwidth to boost the upstream data rate; and Higher layer adaptation, providing support for asynchronous transfer mode (ATM)-based ADSL and packet-based ADSL (for Ethernet). Page 3 of 5

4 ADSL2 is backwards compatible with the earlier ADSL standard and should also lead to improvements in interoperability between chipset suppliers. There is also a lite version offering slightly lower performance but with simpler installation in-line filters in the DSL modem eliminate the need for splitters and offer easy plug-and-play consumer use. Finally, ADSL2+ doubles the downstream bandwidth, enabling downstream data rates as high as 25 Mbit/s on shorter phone lines. Now the standards have been frozen technically, prior to full acceptance in October this year, equipment suppliers have been able to concentrate on building suitable systems. The DSL Forum has already organised three multi-vendor plugfests in the USA open to all ADSL2 system vendors. This has made it possible to test interoperability of chipsets, digital subscriber line access multiplexers (DSLAMs), customer premises equipment (CPE) and test devices. Higher speeds for business and pleasure Ratification of the symmetric high bit rate DSL (G.SHDSL) standard aimed at users of DSL for voice, data and Internet access services by the International Telecommunications Union (ITU) in 2001 led to a revolution in the business market, particularly for small and medium-sized enterprises. G.HDSL offers data transfer rates of up to 2.35 Mbit/s allowing applications such as video conferencing and doubling the distance possible from the exchange compared with the earlier synchronous DSL (SDSL) standard. Such increases in performance could lead to a much wider range of applications in business as well as in the home. Major value-added services include: Peer-to-peer networking a key use that requires symmetrical data rates, continuous high volumes and would be charged on a volume basis; Video-on-demand demanding high downstream data rates, guaranteed for real-time transfer with content- and priority-related charging; and Voice-over-IP telephony necessitating guaranteed data rates, minimum latency and jitter with callrelated charging. Other uses could include online gaming, music services, teleworking and security. Accessing the fibre optic backbone Meanwhile very high speed DSL (VDSL) is set to offer much faster data rates for larger businesses, albeit over shorter distances. VDSL lines will offer data transfer rates from 13 to 55 Mb/s for up to 1500 m and the shorter the distance, the faster will be the connection rate. The intention is to connect consumers premises through existing copper wiring to neighbourhood optical network units that are linked directly to the exchange main fibre optic backbone network. This would enable VDSL users to access the maximum bandwidth available. And it would allow service providers to combine high-quality digital video streams, high-speed Internet access and voice services the so-called triple play using standard copper phone Page 4 of 5

5 lines. VDSL is already being trialled in countries around the world including Italy in Europe although standards questions remain to be resolved. While the European Telecommunications Standards Institute (ETSI), the American National Standards Institute (ANSI) and the ITU have approved basic transceiver technical standards, signal coding problems still remain, with different approaches being promoted by the two main interested groups: The VDSL alliance favours a multi-carrier system line-coding scheme based on discrete multitone (DMT) that is more compatible with existing ADSL technology. The VDSL coalition prefers a cheaper single-carrier line-coding scheme based on quadrature amplitude modulation (QAM) that also consumes less power. Once these problems have been resolved, the sky effectively seems to be the limit! Page 5 of 5