Abstract—In an Customer demand for triple-play services is on the rise, and cable operators have responded by adding services such as Internet access, VoIP, Video on Demand (VoD), and High Definition TV (HDTV) to their standard television service. Unfortunately for carriers and service providers looking to compete with cable and even satellite operators, triple-play services require a great deal more bandwidth than what is currently available over last-mile copper loops. To compete effectively for customer business and to create a future-proof network, carriers and service providers have a critical need for a fiber-fast broadband capability of 50 Mbps to 100 Mbps. While extending fiber to every home seems a logical solution, it is not feasible economically or competitively. Very-High-Bit-Rate Digital Subscriber Line 2 (VDSL2), a standard by the ITU-T. The proposed VDSL2 standard increases the spectrum allocation to 30 MHz for higher performance. VDSL2 enables fiber-fast broadband at speeds of up to 100 Mbps symmetrical—fast enough to deliver broadband applications such as the triple play of voice, data, and video. Keywords— Video on Demand (VoD), High Definition TV (HDTV), Very High Bit Rate Digital Subscriber Line (VDSL) I. INTRODUCTION In order to understand VDSL2’s place in the industry, it is important to follow the history of the ITU standard. In June 1999, the industry cheered as ADSL was standardized by the ITU-T. According too many experts, G.992.1 (G.dmt) and G.992.2, (G.lite) were the standards the industry needed to set the stage for worldwide mass-market deployment of broadband Internet services via copper. Rollouts began, and the 2000 year, there were 5 million ADSL subscribers. Shortly after launching ADSL, the ITU-T committee realized that, while the standard was a great starting point, it needed still improvements in several areas, and they set to work on ADSL2. By 2002, the ADSL2 standard was approved and the industry hailed the extended rate and reach as the defining technologies needed to effectively compete with the cable modem market, especially in the United States. With the introduction of ADSL2+, also known as ADSL2plus, in 2003, carriers and service providers began to see the magic bandwidth numbers needed to effectively deliver video-over-DSL. The ITU standard, G.bond, also known as “BondedADSL2+,” was introduced in early 2005 as a way to double the downstream data rate of copper pairs. It was most effective for customers 6 Kft or more from the central office, so it lacked the short distance and high data rates that video demands. VDSL [1] was ratified in 2003, but service providers concluded that more work was needed on the standard and the new standard, VDSL2 [2], showed the potential of much higher data rates, so the ITU-T continued to hammer out the details for the next-generation of the standard. Shortly after the world celebrated the milestone of 100 million DSL subscribers globally, VDSL2 (G.993.2) [18] was consented in May 2005. With the introduction of VDSL2, the industry will see a major transition from high-speed Internet, which is primarily a data-only service (e.g. web surfing and email), to broadband triple play: voice, video and data. Triple-play service is necessary to offer subscribers all of the essential blocks of communication and information in the same service. The paper is organized as follows: The discrete multi-tome line coding is introduced in Section II and in Section III the frequency plans is examined. In Section IV a comparison between VDSL and VDSL2 is performed and the deployment plans are presented in Section V. II. DISCRETE MULTI-TONE (DMT) LINE CODING A number of factors have converged to make VDSL2 an attractive standard for carriers one of the most important being the selection of a single line-coding method, Discrete Multi-Tone (DMT) [3]. This selection eliminated the line code debate that existed in the past. VDSL2 provides ease of migration from ASDL, ADSL2+, and VDSL, since all these technologies use DMT. Discrete Multi-tone Modulation (DMT) is a multi carrier scheme that is similar to orthogonal frequency division multiplexing (OFDM) used in radio systems like the European broadcast systems for audio and video. III. FREQUENCY PLANS The frequency ranges available for VDSL to use are limited by the need for compatibility with other DSL technologies. In FDD [4], the NEXT crosstalk is avoided through division of the spectrum into individual frequency bands, where each band is unique for either upstream or downstream transmission. This requires that all system in the same cable use the same frequency plan. Very High Bit Rate Digital Subscriber Line (VDSL2) technology for triple play services Ioannis Karamitsos and Alexandros Prosmitis* Department of Information and Communication Systems, University of the Aegean, Samos, Greece * University of Wales, Swansea, UK Tel: (+30210) 6879019, Fax: (+30210) 6879079, e-mail:gkaram@aegean.gr International Conference on Communication, Computer & Power (ICCCP’07) Muscat, February 19-21, 2007 ISSN 1813-419X 375