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|It has been suggested that this article be merged into Very-high-bit-rate digital subscriber line. (Discuss) Proposed since July 2013.|
Very-high-bit-rate digital subscriber line 2 (VDSL2) is an access technology that exploits the existing infrastructure of copper wires that were originally deployed for traditional telephone service as a way of delivering very high speed internet access. The main high-speed link (e.g. a fibre optic connection) terminates at a hub near the customers' location. The existing copper wire infrastructure is then used to carry the high speed connection for the short remaining distance to the customers. It can be deployed from central offices, from fiber-optic connected cabinets located near the customer premises, or within buildings. It has been defined in standard ITU-T G.993.2 finalized in 2005.
VDSL2 is an enhancement to very-high-bit-rate digital subscriber line (VDSL), Recommendation G.993.1, and is the newest and most advanced currently deployed standard of digital subscriber line (DSL) broadband wireline communications. Designed to support the wide deployment of triple play services such as voice, video, data, high-definition television (HDTV) and interactive gaming, VDSL2 is intended to enable operators and carriers to gradually, flexibly, and cost-efficiently upgrade existing xDSL infrastructure.
The protocol is standardized in the International Telecommunication Union telecommunications sector (ITU-T) as Recommendation G.993.2. It has been announced as finalized on 27 May 2005, and first published on 17 February 2006. Several corrections and amendments have been published in 2007 through 2011.
VDSL2 permits the transmission of asymmetric and symmetric aggregate data rates up to 200 Mbit/s downstream and upstream on twisted pairs using a bandwidth up to 30 MHz. It deteriorates quickly from a theoretical maximum of 250 Mbit/s at source to 100 Mbit/s at 0.5 km (1,600 ft) and 50 Mbit/s at 1 km (3,300 ft), but degrades at a much slower rate from there, and outperforms VDSL. Starting from 1.6 km (0.99 mi) its performance is equal to ADSL2+.
ADSL-like long reach performance is one of the key advantages of VDSL2. LR-VDSL2 enabled systems are capable of supporting speeds of around 1–4 Mbit/s (downstream) over distances of 4–5 km (2.5–3 miles), gradually increasing the bit rate up to symmetric 100 Mbit/s as loop-length shortens. This means that VDSL2-based systems, unlike VDSL systems, are not limited to short local loops or MTU/MDUs only, but can also be used for medium range applications.
Bonding (ITU-T G.998.x) may be used to combine multiple wire pairs to increase available capacity, or extend the copper network's reach.
The standard defines a wide range of profiles that can be used in different VDSL deployment architectures; in the central office, in the cabinet or in the building for example.
|Profile||Bandwidth (MHz)||Number of downstream carriers||Carrier bandwidth (kHz)||Power (dBm)||Max. downstream throughput (Mbit/s)|
Vectoring is a transmission method that employs the coordination of line signals for reduction of crosstalk levels and improvement of performance. It is based on the concept of noise cancellation, much like noise-cancelling headphones. The ITU-T G.993.5 standard, "Self-FEXT cancellation (vectoring) for use with VDSL2 transceivers" (2010), also known as G.vector, describes vectoring for VDSL2. The scope of Recommendation ITU-T G.993.5 is specifically limited to the self-FEXT (far-end crosstalk) cancellation in the downstream and upstream directions. The far end crosstalk (FEXT) generated by a group of near-end transceivers and interfering with the far-end transceivers of that same group is cancelled. This cancellation takes place between VDSL2 transceivers, not necessarily of the same profile.
Although technically feasible at the moment vectoring is incompatible with local-loop unbundling but future standard amendments could bring a solution.
|It has been suggested that this section be split into a new article titled VDSL2 Deployment. (Discuss) Proposed since August 2014.|
|Isle of Man|
|United Kingdom||BT Group trialled VDSL2 in the Muswell Hill, London and Whitchurch, Cardiff Exchanges starting in July 2009. On 23 March 2009, they announced plans to deploy the service to 29 exchanges throughout England, Wales, Scotland and Northern Ireland. On 9 July 2009, they announced plans to deploy the service to a further 69 exchanges throughout the UK by the summer of 2010.|
May 2010 BT announced £2.5 billion plans to roll out a mixture of VDSL2 FTTC (75%) and GPON FTTP (25%) to 66% of the UK by 2015 with VDSL2 speeds starting at 40 Mbit/s down 10 Mbit/s up potentially rising to 60 Mbit/s down 15 Mbit/s up. In October 2011, BT announced that this roll-out was being accelerated such that it will be completed by 2014 (one year earlier than originally planned). April 2012 BT to introduce new product download speeds of up to 80Mbit/s down and 20Mbit/s up on its VDSL2 network. This has been achieved by increasing ANFP spectrum usage to 17 MHz. BT announce FTTP On Demand - a GPON based service to extend the fibre overlay in FTTC areas direct to the home to subscribers willing to pay (install costs not yet announced expected to be in high hundreds of pounds).
On 8 October 2009, it was revealed that Virgin Media will trial VDSL2. Residents of Higher Pill, in Saltash, and nearby Hatt will be offered free broadband via a VDSL2 line to a roadside cabinet. The cabinets will be linked to Virgin Media backhaul via new fibre laid by Vtesse Networks through BT's local exchange, 5 km away. The trial eventually resulted in Vtesse networks running the final service without Virgin Media's involvement under their own brand on 1 October 2010.
Digital Region Ltd, an EU government-backed project formed by the four main councils in South Yorkshire – Sheffield, Rotherham, Doncaster and Barnsley, along with the Regional Development Agency, Yorkshire Forward, have rolled out VDSL2 services to over 80% of the county. The infrastructure consists of 1360 FTTC nodes (fibre to the cabinet) connected to over 1200 km of both new and existing fibre-optic cable. The service is delivered utilising the sub loop unbundling product (SLU)from BT Openreach to provide the last-mile connection to the consumer via existing copper. The network initially offered up to 40 Mbit/s downstream and up to 10 Mbit/s upstream with an assured level of service. It is already capable of delivering speeds of 70Mbit/s down/30Mbit/s up using the 17a spectrum profile, and it was announced in May 2012 this will increase to 100 Mbit/s down and 30 Mbit/s up in the future. There are a number of ISP's currently interconnected to the network (Ask4, Digital City, Fluidata, LittleBigOne and Origin Broadband) offering residential, business and wholesale connectivity services.
Origin Broadband joined the Digital Region network in January 2011. They were the first ISP to specifically advertise uncapped, unlimited, up to 40Mbit broadband, to residential customers on the Digital Region network. On April 18, 2012 it was announced they will be increasing their offering to include an "up to 100Mbit down, 30Mbit up" package, still with no limits on usage, in May 2012.
LittleBigOne also joined the network in 2011, offering 40Mbit/s VDSL services, including the first UK IPTV over VDSL service, which launched in early 2012. They will also be offering an "up to 100Mbit" service starting in May 2012.[dated info]
On 14 April 2010, Rutland Telecom announced that it is to deliver broadband speeds up to 40 Mbit/s using a fibre to the cabinet solution in the Welsh notspot village of Erbistock. The initiative, backed by private investment, will be the first time that VDSL2 technology has been used in a Welsh rural village.
|Bahrain||Lightspeed Communication announced that they will begin deploying VDSL2 technology for residential and business customers in 2012. Downstream speed will be up to 80 Mbit/s. The service is yet to launch as of July 2013.|
|Hong Kong||PCCW Limited (Netvigator) and Hutchison Global Communications (HGC) have deployed VDSL2 technology to serve residential and business customers since 2008. Netvigator provides up to 100 Mbit/s downstream and 30 Mbit/s upstream broadband service in VDSL2, while HGC asserts that to provide up to 100 Mbit/s downstream and 100 Mbit/s upstream service. However, due to equipment technical difficulties, HGC connection is pretty unstable. HGC is able to provide both 50 Mbit/s downstream and upstream in most districts of the coverage.|
|India||MTNL has deployed VDSL technology in Mumbai and offers up to 20 Mbit/s downstream. |
Airtel has announced 50 Mbit/s Plans using VDSL2.
|Israel||Bezeq has deployed FTTx with VDSL2 with brand name NGN in September 2009 offering speeds of 20 and 30 Mbit/s downstream and 1 Mbit/s upstream. In October 2010 Bezeq has deployed 50 and 60-100 Mbit/s downstream speeds and limited upstream speeds of up to 1 Mbit/s.In April 2012 Bezeq has limited upstream speeds to 1.5 Mbit/s. In the beginning of 2013 Bezeq will deploy 200 Mbit/s downstream speed using two copper pairs bonding.|
|Macau||CTM start to test VDSL2 at the 3rd season of 2007. First will be tested in two main buildings in Macau.|
|Malaysia||Telekom Malaysia deployed FTTx and VDSL2 with brand name UniFi in March 2010 offering symmetrical speeds of 5, 10 and 20 Mbit/s.|
|Pakistan||PTCL is the first service provider worldwide to deploy a commercial VDSL2 Bonding solution and offers speed up to 50 Mbit/s - The highest speed offered by any Internet Service Provider in the country.Sky Telecom is also VDSL service provider in AJK. It also deploy fiber network for commercial users.|
|Saudi Arabia||Saudi Telecom Company (STC) The Largest Operator in Middle East launched VDSL2 service in December 2011 offering various speed packages including 40 Mbit/s Downstream and 10 Mbit/s Upstream to provide Triple-play services including High-Speed Internet (HSI), IPTV (SD and HD) and VoIP from single VDSL CPE with built-in Wi-Fi. This complements STC's existing ADSL2+ installed base which already offers download speed of up to 20 Mbit/s as part of Fixed Broadband Access (FTTx) Network|
|Singapore||SingTel tied up with Ericsson to deploy a technical trial of VDSL2 starting June 2006. However, no service plans announced yet and SingTel is preferring FTTH over VDSL2.|
|Sri Lanka||Sri Lanka Telecom announced the soft launch of its VDSL2 advanced fixed broadband technology on May 2013 and is planning to expand the service in the near future.|
|Taiwan||October 2007, Chunghwa Telecom (CHT) has awarded ZyXEL Communications to provide VDSL2 equipments (DSLAM and CPE) for its "Next Generation Access Network" project. The project involves 340-thousand lines and will provide high speed Triple play services to these subscribers.|
|Dominican Republic||Claro offers speeds ranging from 1Mbit/s down and 256kbit/s up to 50Mbit/s down and 2Mbit/s up. The upgrade to VDSL2 was required to provide enough bandwidth for the company's IPTV, data, and voice services all running on their POTS network.|
|Argentina||IPLAN Telecomunicaciones is beginning to deploy Allied Telesis VDSL2 equipment to replace old LRE Cisco equipment among their 10K customers in Buenos Aires.|
|Brazil||GVT is using Zhone Technologies, Inc. Equipment to provide VDSL2 service to Belo Horizonte, Salvador, Brasília, Curitiba, Goiânia, Porto Alegre, Caxias do Sul, Campina Grande, Recife, Fortaleza, and other medium and small cities.|
Sercomtel has deployed a new VDSL2+ network on Londrina city. Reaches speed up to 30Mbit/s on downstream, and 15Mbit/s upstream.
TIM has launched their VDSL2 service in some locations from São Paulo and Rio de Janeiro, also known as "TIM Live". Two packages are available, 35Mbit/s on downstream (20Mbit/s upstream) and 50Mbit/s on downstream (30Mbit/s upstream).
|Chile||Movistar is beginning to deploy Huawei VDSL2 equipment to some sectors in the city of Santiago.|
|South Africa||Telkom SA is in the early stages of trialing VDSL2 enabled MSAN exchanges, with target speeds of 10, 20, 40Mbit/s download. It is planned that there should be a full replacement of all current DSLAM's with the new MSAN cabinet units, enabling a shorter local loop. The trialing will begin in August 2012 However Roll-outs have stopped in October 2013, and has of yet not started in 2014.|