VDSL Splitter: The Basics and Variants

MELONTEL – Your professional VDSL Splitter factory and supplier in China! As a leading Chinese communication equipment manufacturer, our expert will show you everything about the VDSL splitter. Continue reading to learn more.

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Your Professional VDSL Splitter Manufacturer

VDSL Splitter

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A VDSL splitter that takes in a multi-frequency signal with both POTS and VDSL components and splits it into its component signals. The VDSL splitter box has three outputs: one for POTS, one for VDSL, and one for the multi-frequency signal that it receives.

On the other hand, a POTS signal conditioning network is integrated into the VDSL splitter and is wired to both the input port and the output port. The POTS signal is converted from a multi-frequency signal at the input port to the POTS signal at the output port using a signal conditioning network.

A VDSL signal conditioning network is integrated within the VDSL splitter device, with connections to both the input and output ports. The VDSL signal conditioning network takes in the multi-frequency signal at the input port and sends out the VDSL signal at the VDSL output port; it does this by using a voltage blocker and a VDSL high-pass filter.

To allow for the transmission of both voice and data over the same twisted pair (the POTS + DSL line), a DSL over POTS splitter is used to partition the transmission of the two signals. To prevent the POTS signal from being disrupted by the DSL signal, the splitter also acts as an isolation device. Furthermore, it protects the DSL signal from transients introduced by the POTS itself.

High frequency DSL signals can be attenuated and heard as noise on some phones when DSL and PSTN, or Public Switched Telephone Network, share the same line since phone electronics demodulates high frequency signal outside its operating range to voice frequency noise. In order to prevent these systems from interfering with one another, the telephone line must be used to physically separate them.

By preventing interference between the phone and DSL systems, a DSL POTS Splitter/filter enables the full utilization of the copper line frequency spectrum’s bandwidth.

The signal from the phone’s output is often merely low-pass filtered, allowing voice frequencies (up to 3.4KHz, some say 4KHz) to get through while filtering out higher frequencies. The most common type of filter used for this purpose is a low-pass LC filter with an operating frequency between 4 and 20 KHz.

By dramatically reducing the strength of the DSL signal’s higher frequencies by at least 30 dB with a suitable filter, this type of filter ensures that your telephone equipment receives less of the signal and less of the potential noise it could generate.


There are three distinct bandplans defined by the VDSL1 standard: Annex A (Asymmetric BandPlan), Annex B (Symmetric BandPlan), and Annex C (Unidirectional BandPlan). Plan 998 and Plan 997 have been renamed to Annex A and B, respectively.

The configurable separation frequency between the second downstream band and the second upstream band is unique to VDSL1 Annex C, which is designed for use solely in Sweden. In order to use the full 12 MHz of available spectrum for all VDSL1 bandplans, the copper loops must be significantly shorter than those used by ADSL.

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For the widespread rollout of “triple play” services including voice, video, data, and high-definition television, VDSL2 has been improved upon (HDTV) VDSL2 is meant to allow operators and carriers to upgrade existing xDSL infrastructure in a gradual, flexible, and cost-effective manner.

As Recommendation G.993.2, the protocol has been standardized by the Telecommunications Sector of the International Telecommunications Union (ITU-T). On May 27, 2005, it was officially proclaimed as complete, and on February 17, 2006, it was released to the public for the first time. From 2007 through 2011, a number of updates were released to address various issues that had been discovered.

VDSL2 enables the transfer of aggregate data speeds of up to 300+ Mbit/s downstream and upstream on twisted pairs with a bandwidth of up to 35 MHz. From its theoretical maximum of 350 Mbit/s at the source, it drops swiftly to 100 Mbit/s at 500 m (1640.42 ft) and 50 Mbit/s at 1000 m (3280.84 ft), but thereafter it drops at a considerably slower rate and surpasses VDSL beyond that distance. Its performance is on par with ADSL2+ from a distance of 1,600 meters (1 mi).

One of the main benefits of VDSL2 is that it provides long-range performance on par with ADSL. LR-VDSL2 enables systems to provide downstream rates of 1-4 Mbit/s across a range of 4-5 km (2.5-3 miles), with the bit rate increasing to a maximum of symmetric 100 Mbit/s as the loop-length decreases.

As a result, VDSL2-based systems can be used for medium-range applications, unlike its predecessors, which were restricted to small local loops or MTU/MDU only.
Bonding (ITU-T G.998.x) allows numerous wire pairs to be combined to boost capacity or to extend the reach of the copper network. xDSL and wireless networks can be integrated via Hybrid Access Networks. Network providers can now offer improved Internet connection speeds even across large distances.


With Vplus, users can get faster speeds over their current VDSL2 connections. VDSL2 profile 35b, created by Alcatel-Lucent, was standardized in November 2015 by the International Telecommunication Union (ITU) in its document G.993.2 Amendment 1.

On loops less than 250 meters in length, it claims throughputs of up to 300 Mbit/s downstream and 100 Mbit/s upstream. Vplus’s vectoring speed degrades to that of VDSL2 17a over longer loops. Since Vplus (35b) and VDSL2 (17a) have the same tone spacing, mixed deployments and a seamless transition to Vplus are possible.

Do ADSL Filters Work with VDSL?

The AFL VDSL2 Splitter/Filter is compatible with both standard ADSL and ADSL2+ connections. The method and degree of separation between POTS and xDSL signals is what differentiates the AFL Splitter/Filter from DSL filters.

This is true for both the method and the degree of separation. The AFL Splitter/Filter acts similarly to a DSL filter in that it separates voice from POTS; however, in addition to this, it also separates the VDSL signal from POTS to a significant extent. AT&T’s VDSL2 8a profile, which ranges from 25 kHz to 8.5 MHz, can be separated out with the use of the AFL Splitter/Filter.

Everything that operates in this frequency range, which includes ADSL and ADSL2+, is compatible with this filter.

Does VDSL Need a Filter?

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To put it simply, it is impossible to give a definitive response to this query. A filter is unnecessary if your internet service does not include a landline. You will require a filter at your NID if you have both a VDSL and a landline or POTS line.

The network interface device (NID) is the hub from which all other jacks in your home’s phone system radiate.

When comparing VDSL and ADS, you’ll quickly realize that they’re very distinct offerings. The fact that they operate at various frequencies necessitates that each be filtered out separately. When using VDSL or ADSL service, problems like slow surfing and dropouts can occur if the wrong splitter filter is installed.

At the NID, a VDSL splitter filter is always present (network interface device). While most ADSL filters are implemented at the network interface device (NID), they can also be placed at the entry point, the telephone jack.

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Difference Between ADSL Splitter and VDSL Splitter

Very High Bitrate Digital Subscriber Line, also known as VDSL or VHDSL, is a more advanced form of the technology we use to access the internet known as ADSL, or Asymmetric Digital Subscriber Line. Because of the differences in methodology, you generally can’t use the tools from one in the other.

When comparing the two technologies, speed is the most important factor to consider. The maximum transfer rates for ADSL are currently set at 8 mbps down and 1 mbps up. As a comparison, VDSL can offer as much as 52 mbps download and 16 mbps upload.

Since VDSL can support far higher data rates than ADSL, it is being considered as a promising technology for high-bandwidth uses like VoIP telephone and HDTV transmission. VDSL’s utilization of seven separate frequency bands for information delivery is another major benefit.

The user can then decide which frequencies to use for downloading and which for uploading. Very useful if you need to host files that will be downloaded frequently.

The requirement for close proximity to a telephone exchange is VDSL’s biggest downside. It’s possible to approach top speed for around 300 meters, but after that, the line quality and speed start to rapidly degrade.

As a result, unless you are exceptionally close to the telephone exchange of the business to which you pay, ADSL remains the better option. The majority of VDSL customers are large corporations that have an urgent need for a lightning-fast server and so tend to locate their own servers in close proximity to the provider’s.

VDSL is only widely available in certain countries like South Korea and Japan due to its expensive price and technical restrictions. While VDSL is available in certain other countries, typically only a couple of service providers in each country deal with it. By contrast, ADSL is extremely common and is available in every country that has high-speed internet.

VDSL2 In-Line splitter

When used in conjunction with vDSL2 technology, a VDSL POTS Splitter acts as a passive low-pass filter to deliver POTS service. Voice equipment is protected from interference by the device, while the xDSL link is kept free of data mistakes caused by POTS noise.

The Bell System planned to expand by incorporating internet service into its existing wired network. It was easy to implement DSL because although it is possible to carry both voice and data over a single pair of wires by allocating additional bandwidth and frequency to the wired network, doing so presents a number of challenges.

With a splitter, you can use a single telephone line for both voice and data transmissions—whether via a digital subscriber line (DSL) modem, as in an ADSL or VDSL connection, respectively.

The groundbreaking VDSL2 Splitter from Comtest, the universal POTS Splitter, can be installed in a variety of settings, including wall mount, flush mount, and multi-dwelling units (MDUs), drastically cutting down on labor, materials, and overall cost.

This universal splitter is ADSL2+ and ADSL compatible in addition to being a full VDSL2 splitter. The Universal splitter’s sealed cavity and gel-filled IDC connectors make it ideal for usage in any setting, from the NID outside the home to the wall plate inside an apartment.

Benefits include fully weatherproof for use in the great outdoors, modular construction allows for easy installation in any setting, whether that’s a single family house, an apartment complex, or a suppression of Surges and Lightning, secondarily resilient to sudden voltage fluctuations, fast and secure installation is ensured by this tool-free IDC that uses a gel-filled connector, and tab for NIDS Ground Post optional mounting.

VDSL Filter

Filters for your DSL line are essential. But don’t worry; this won’t prevent your service from functioning. DSL can function to some extent without dial tone filtering. Internet problems such as poor connections and interruptions are possible, but for the most part, you should be able to use the web normally.

Call your ISP if you’re having trouble with your DSL connection so they can check your line. If problems are discovered, a repairman will be sent to your house.
Installing a DSL line filter at both the modem and each phone jack can fix a lot of problems. The filters will be labeled on both sides with “tel/phone” or “modem,” making it simple to determine which port to use for your phone or modem.

You should always use a filter prior to connecting your router while using DSL service. Just connect your modem’s phone wire to the splitter’s “modem” jack and you’ll be good to go with a typical DSL filter. If you do this, your modem won’t pick up any unwanted frequencies from your landline.
You can choose to have a filter at your NID, or none at all if your service is functioning properly without one.

Splitter VDSL Orange

This is an ADSL filter that has been tele permitted and is Chorus approved. Equipped with a BT phone socket and an ADSL/VDSL jack. Pairs with a standard BT phone jack.

With this, ADSL, ADSL2+, VDSL, and VDSL2 are all supported. Please specify if you have a preference for a certain color, brand, or model. Note that this item may be generic, D-Link, or Dynalink and may be black, beige, or white.

The DSL-12MF-NZ and DSL-13MF-NZ are the two variants produced by D-Link.

Final Thoughts

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Because several major telecom providers, including ATT and Verizon, still offer VDSL, it’s important to know whether and when you need to install a filter on your service.

A filter is an absolute must if your service relies on a landline connected to the internet. It is not necessary to use a filter on your internet connection if you do not have a landline. The NID filter should be installed by every technician as a matter of course, but this is not often done.