Rostelecom is one of the leading providers in the Russian market of communications services. It is not surprising that many users prefer its services. On top of that, the company, along with the tariff package, also provides the basic equipment necessary to connect to the Internet. But many people try to set access parameters on their own, which sometimes causes some difficulties. Meanwhile, if you figure it out, there shouldn’t be any special difficulties. Next, we propose to consider setting up a Rostelecom modem of any type. This instruction will be useful not only for the equipment supplied directly by the company, but also for any other similar models.

Modem market overview

Before setting up the Rostelecom modem is considered directly, it is necessary to dwell on the equipment that will be used to organize an Internet connection at home or in the office.

What can you use at the moment? Among the most popular options, there are several main groups of devices:

• modems-routers (DSL/ADSL);
• Ethernet modems;
• USB modems;
• 3G modems.

The first group is the most popular and is suitable for installation at home or in offices. The approximate cost of the simplest model is about 800 rubles, but models of a higher rank will cost about 1,500 rubles.

USB routers have not gained much popularity, although they are quite cheap. Their main problem is that very often there are situations with “gathering” of drivers. 3G devices are mainly used when moving around the city with a laptop.

Which model should you prefer?

Which of all this should you choose to install at home? It seems that the best option would be to use modems that combine the capabilities of a DSL or ADSL router (for access via Wi-Fi).

Among the most commonly used devices are models D-Link, TP-Link, Intercross, Zyxel, etc. The settings of some of them will be discussed below.

General rules for connecting ADSL modems

As follows from the basic understanding of ADSL technology itself, a modem uses a regular telephone line to provide access to the Internet.

When connecting a modem to it, the best option is to install a special one that allows you to simultaneously access the Internet and make phone calls. In other words, the telephone line is not blocked, unlike a direct connection.

Connecting all devices follows the sequential diagram: computer - modem - splitter - telephone line. Actually, even a child can figure this out, especially since the splitter has two sockets for different cables, so it’s simply impossible to confuse something.

Driver installation issues

After the entire circuit is assembled and the power supply is connected, you need to install special control software called drivers (so that the operating system installed on the computer can initialize the device, and it, in turn, works without failures).

Standard models, as a rule, are recognized automatically by the system, and installing drivers does not raise any questions. If something goes wrong, you can always use the special disk that should come with the modem. If you did not purchase the modem from the provider or if there is no disk, you can download the necessary drivers directly on the official website.

When the entire procedure is completed and the device becomes fully operational, the Rostelecom modem should be directly configured. The first step is to access the web interface of the device itself.

Enabling and accessing the web interface

As a rule, for all devices, the combination 192.168.1.1 is entered in the address bar of any web browser installed on the computer. Setting up a Rostelecom modem in the first stages involves setting the correct parameters for accessing the Internet. If Wi-Fi is supported, you will then need to install these options.

The login and password that will be requested when attempting to access is admin. If for some reason the modem does not accept the entered data, you must reset all parameters by pressing the Reset button on the back of the modem and re-enter the information.

To configure any modem in the simplest case, if manual intervention is not required, you can use the disk supplied with the device, which contains a specialized utility in the form of a kind of “Hardware Configuration Wizard”. After it starts, you just need to follow the instructions of the installer.

Setting up a Rostelecom DSL modem or ADSL device

But let’s assume that the user does not have the disk at his disposal (it got lost, became unusable). What to do in this case? There is no need to despair, since setting up any type of equipment is quite simple.

So, for Rostelecom, setting up a D-Link modem (just taking it as an example) begins with setting the connection type. It is advisable to set the value of this parameter to PPPoE and not use a “bridge” scheme, which can block access to the Network when the main terminal is turned off.

Next, you should manually enter the VPI and VCI parameters, which must correspond to the selected region of the user’s location (for Moscow these are values ​​0 and 35). These parameters must be included in the contract, but you can find them out from the technical support service, even just by calling (although they are almost always set automatically).

Next, you need to enter the registered user name (PPP), specify the login, enter and confirm the password, select the name of the service, check the Keep Alive checkbox and specify the values ​​of the LCP interval and LCP failure options (15 and 2, respectively).

Finally, at the very bottom you need to check the IGMP box and save the changes made. After exiting the modem interface, you can use the Internet even without rebooting the operating system, but with a mandatory reboot of the modem (just click on the appropriate button).

Setting up a TP-Link Rostelecom modem

With devices of this series the situation is much simpler. The fact is that the devices themselves already have, so to speak, a built-in utility called Quick Start.

In fact, setting up the Rostelecom TP-Link modem comes down to just selecting the connection mode (PPPoE), setting the time zone and entering a login and password. Basically, why not the same “Setup Wizard”?

Nuances of setting Intercross parameters

The settings of the Intercross (Rostelecom) modem are somewhat different from what was described above.

When entering the web interface, you first need to select to launch the “Wizard”, leave the value of the VCI parameter, set by default at 35, unchanged, and enter the value 8 for the VPI parameter.

Next, the connection type is set to PPPoE, and the points for automatically obtaining an address (Obtain an IP address automatically) and NAT availability (Enable NAT) are also noted. The address field is left blank. After this, the username and password are entered.

In the following steps, you don’t have to change anything, and after viewing the information, in the final step you just need to save the settings.

Wi-Fi options

Finally, let's see what it means to set up a Rostelecom WiFi modem. In fact, such a modem can be used as a regular router for distributing a wireless signal.

There is nothing particularly complicated here either. Setting up the Rostelecom modem in this case involves entering the following values ​​and parameters:

• Authentication Type - WPAPSK.
• Encryption - AES.
• SSID - arbitrary connection name.
• Pre-shared Key - your own password for accessing the Wi-Fi connection.

After completing all the settings, you need to go to the Maintenance tab and use the browse button to select the romfile.cfg file with automatic add-in parameters. At this point, the setup can be considered complete.

Brief summary

As a summary, it remains to be said that setting up a Rostelecom modem of any known type is not particularly difficult. The main thing is to choose the right parameters that were presented in the material above.

As for the choice of equipment, ADSL devices, when using a connection from the Rostelecom provider, are the best option compared to the same Ethernet or USB devices, which are quite limited in their capabilities.

The settings of 3G modems were not considered, since, after all, users at home or in the office give the main preference to modems that combine the functions of routers with wireless communications. Well, in terms of settings, if I would recommend something very simple, it is best to use the “Wizard” disk so as not to deal with unnecessary things. But if this is not possible, you can safely use the instructions given above.

Greetings! Today’s article is addressed to those who have home Internet via a telephone line using a connection via an ADSL modem or router with the appropriate “telephone” port. Many providers still work with this option, usually providing not only Internet services, but also telephony or digital TV. The connection diagram is built a little differently, which means that setting up wifi via an ADSL modem router happens differently.

How to connect an ADSL modem to a wifi router?

Let's consider two possible schemes for setting up an ADSL modem and router using the Internet via ADSL technology. When the provider employee who connected the Internet leaves you, the diagram looks like this:

1. The telephone cable is connected to a splitter (a tee that splits the plug for the telephone cable).
2. From it, one telephone wire goes to the landline telephone itself, and the other to the ADSL modem.
3. And from the modem the network cable is connected to a connector on the computer.

The first way to distribute such Internet via wifi is to make one additional link in the form of a regular wifi router. We simply connect it to an ADSL modem and a computer with a network cable (from the modem to the WAN port, from the PC to the LAN), and we get the following diagram:

To create this structure we can use two methods:

1. So that the modem operates in bridge mode, and the router operates as a router (Router, RT) or access point (Access Point, AP). In this configuration, all Internet connection settings are made not in the ADSL modem, but on the computer or, in our case, in the router.
2. The other is when, on the contrary, the modem is configured to connect to the provider, and the router simply extends this signal.

The second option is quite simple. You do not touch anything in the settings that your provider’s employee has already made when connecting, but simply configure the router to receive a dynamic IP address and activate the function of dynamic distribution of addresses over the DHCP network.

The first one is a little more complicated, so let's figure out how to implement it using the example of the most common budget ADSL modem model, D-Link. First of all, insert the telephone cable (with a small connector) into the corresponding ADSL connector of the modem, and into the LAN connector - the patch cord that we use to connect it to the PC.

The adsl setup itself is located on the computer. Go to Windows 7 “Start > Control Panel > Network and Internet > Network and Sharing Center > Change adapter settings.” Here we find “Local Area Connection”, right-click and select “Properties > TCP/IPv4 Protocol” and set the receipt of all settings to automatic.

After that, go to the browser at http://192.168.0.1 - this is the network address in the admin panel of the D-Link modem. Enter the login-password pair admin-admin.

In the menu, go to the “Quick Setup” section, uncheck the “DSL Auto Connect” box and enter the values ​​for VPI and VCI - they should be specified in your service connection agreement or ask your provider. In the “PORT” item we leave “0”.

After that, click the “Next” button and check the “Bridging” value, that is, we switch the modem to bridge mode.

Next, check the “Enable Bridge Service” checkbox and set a name for our bridge. Then on the next page we write down the IP address and mask of our modem, that is, 192.168.0.1 and the standard mask 255.255.255.0.

Click “Next” again, look at all the final settings and click the “Save/Reboot” button to apply all the changes. The modem will reboot. We also reboot the computer so that it receives a new network IP.

Let's move on to the router. First of all, we take out the patch cord from the PC, connect it to the router, and the router, in turn, connects it with the same patch cord (RJ-45 cable) - to the modem via the WAN connector, and to the computer via LAN. If you work with Asus routers, then it will look like the screenshots below. Go to the “WAN” menu section and select PPPoE as the connection from the drop-down list. Next, enter all the data provided by the provider (login, password, possibly something else). And we apply all these settings.

That's it, after this your router, through the mediation of an ADSL modem, should start broadcasting the Internet.

Setting up an Asus ADSL router

The second method is that we remove the ADSL modem link from the diagram and replace it and the router with a single device - a WiFi router with support for ADSL connections.

It looks the same as a regular router, only with a socket for inserting a telephone cable. Zyxel, TP-Link, D-Link, Acorp - any brand of network equipment has such a device in its model range. As an example, I suggest that you first familiarize yourself with the Asus DSL N-12U model.

All connection settings will be made in the admin panel of the router itself. First you need to connect the telephone cable to the ADSL modem router, and the Ethernet patch cord to the computer. We go to the address - you already know which one 100 times - enter the well-known login and password if you still haven’t changed them (by the way, if you forgot them, you can look at the bottom of the router).

We go to the settings page, select manual settings, select a provider from the list, the settings for which are already built into the device. If it is not there, then select “Not in list”. Here you will also need to fill in all the parameters for VPI, VCI, Protocol and Encapsulation Mode,

and also in the next step your login and password for access. All this can be found out from the provider or from the contract.

These were the modem part settings. Now let’s go to the router room, set the network identifier and encryption keys.

How to configure a TP-Link ADSL modem?

Now we’ll look at the more sophisticated ADSL modem-router TP-Link Archer VR400 with a USB input, to which you can later connect a printer or 3G modem.

Here we will also use the quick setup, which is located at http://192.168.0.1. We are greeted by a new, nice, minimalistic interface.

I hope I answered the question “How to connect an ADSL modem through a router”

For a snack - step-by-step video instructions for different models:

ADSL technology with the proliferation of leased lines is gradually becoming a thing of the past, but some providers continue to offer it to their clients. If there are no other options for connecting, and you want to access the Internet not from one computer, but from several devices, then it will be useful for you to learn how to set up a wifi router via an adsl modem.

Connecting equipment

To install the equipment correctly, you need not only an ADSL modem, but also a number of other devices, without which you will not be able to connect to a PC and telephone line. First of all, we are talking about a splitter and a network card, which is needed to transfer data between a computer and a modem.

A splitter is needed to simultaneously connect a telephone and a modem to the line.

Typically, a splitter has several slots:

• Line (telephone line).
• Modem (for connecting a modem).
• Phone (to connect a phone).

The equipment connection procedure is as follows:

After installing the listed equipment, you can proceed to setting up the ADSL modem. In most cases, all network devices are configured according to the same principle with minor changes related to the requirements of providers.

The ADSL modem can operate in two modes – “bridge” and “router”. The first one is ideal if you use one computer to access the Internet.

The “router” mode is installed when it is necessary to connect two or more machines to the network.

To access the modem interface, you need to specify the TCP/IP protocol parameters:

After completing these steps, you will be able to connect to the modem to change its configuration.

Changing the modem configuration

The ADSL modem parameters are configured through its interface, which is accessible through any browser at 192.168.1.1 (the address may vary depending on the model or manufacturer; check this parameter in the documents for the device).

After identification using the admin/admin pair, you will be taken to an interface where information about the device will be indicated on the start page.

Once you have entered all the required information, click “Save” to apply the new configuration.

Create a connection on your computer

After you set up the ADSL modem, you need to create a new connection on your computer. If you know how to set up the Internet on Windows 7, then you can quickly cope with this task:

A new connection has been created, you can now connect to the Internet on one computer. However, we are interested in a slightly different result, so we continue setting up the equipment.

Setting up the router

The router, like the ADSL modem, requires separate configuration, for which you need to connect the router using a patch cord to the computer’s network card.

Important: in order for the router to access the network, it must be connected to a previously configured modem.

Do not mix up the connectors: one end of the patch cord is installed in the LAN port on the modem - roughly speaking, the Internet will “exit” from here. The second end of the cable is inserted into the WAN port of the router - the router will receive the Internet and distribute the network.

Be sure to reset your router, even if you just brought it from the store. Find a narrow hole on the router body labeled “Reset.” Take something thin (a pin or needle will do), insert it into the hole, apply pressure and hold for 10 seconds. All router settings will be reset to factory settings.

Now you can open the router’s web interface and configure the connection:

If the connection is established correctly, you can proceed to setting up your wireless network. It is done according to the standard scheme in the “Wireless” or “Wi-Fi” section. Specify the wireless network name, encryption protocol, and security key. All changes made must be saved, after which the router reboots.

Internet access

The equipment is connected and configured, you can move on to the most awaited stage - connecting to the Internet.

Make sure that the “DSL” and “Internet” indicators on the front panel of the modem are lit. The first diode signals the presence of a connection with the provider, the second indicates that the Internet is connected.

The “WAN” indicator on the router should be lit, indicating a connection with the modem and, accordingly, the provider.

If all the necessary indicators light up, connect to your computer and try to access a website through a browser. Then run a search for access points on your laptop, tablet or smartphone and try to connect to the wireless network created using the router.

Alternative option

If all these ups and downs of installing and configuring equipment seem too complicated to you, think about purchasing a new ADSL modem model that has a built-in function for distributing the Internet over a wireless network.

Contact your provider - perhaps he himself sells such devices or can suggest a manufacturer and model that meets all his requirements.

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ADSL splitters. Device. Connection diagrams

How to connect ADSL splitter correctly

Screenshots are taken from the documentation for modems ZyXEL, HUAWEI, D-Link, etc.

Let's consider the connection option using the ZyXEL AS 6 EE splitter as an example.

Fig.1.1. Connecting an ADSL splitter. The most common option.

1. To the connector LINE splitter connects a city telephone line. This connector is sometimes called LINE-IN, for example ECI-TELECOM splitters. I haven't seen any other options.

Branches or branches are not desirable. This significantly reduces the reliability of the ADSL modem. If there are taps/branches to the splitter, then telephone sets must be turned on through “microfilters”. Instead of a microfilter, you can use another ADSL splitter.

2. To the connector MODEM splitter connects an ADSL modem. In ECI-TELECOM splitters this connector is sometimes called LINE-OUT, in D-Link splitters this connector is called ADSL. SIEMENS calls it NT(Network Termination).

3. To the connector PHONE The splitter connects telephones, faxes, mini-PBXs, Dial-UP modems, etc. Everything that previously hung on this phone number will now be included in the splitter, in the connector PHONE! This connector is sometimes called TEL, - D-Link splitters, microfilters, ISDN splitters. For SIEMENS splitters this connector is named POTS(Plain Old Telephone Service).

Fig.1.2. ADSL splitter ZyXEL AS 6 EE.

Fig.1.3. A general option for connecting the ZyXEL AS 6 EE ADSL splitter, using the ZyXEL 660H modem as an example.

How to connect ADSL splitter.

We use telephone wire of the highest quality. Do not use power cables. It is advisable to completely get rid of the TRP cable ("noodles under the nail").

Indoors, the distance from the ADSL splitter to the ADSL modem can be any. But the total distance between your ADSL modem and the provider modem (DSLAM) installed on the PBX should not exceed the theoretical 5-6 km. (Length of cable)

The best option is to run a CAT 5 twisted pair from the CRT on the landing to the splitter and from the splitter to the ADSL modem. For example: UTP twisted pair cable, category 5, 2 pairs, solid UTP2-C5E-SOLID-GY

Fig.2. Double cable.

The two-pair cable is ideal for termination under RJ11. For the line, take a blue or orange pair. It is prohibited to take wires from different pairs!

Splitters use RJ11 connectors, but in older ECI-TELECOM models and ISDN splitters from ZyXEL the connector MODEM replaced with RJ45.

All splitter connectors use two central contacts.

Possible options for connecting ADSL splitter.

Cascade connection. Such a connection is not possible with SIEMENS splitters; their NT/ADSL output is isolated by capacitors. Direct current for a phone connected to the second splitter will not pass.

Fig.3.1. Cascade connection.

The connection diagram in Fig. 3.1 is used in desperate situations when it is impossible to change the telephone wiring in the room. This is a last resort option and is not recommended. Sometimes, in order to save money, a microfilter/splitter is not used at all.

As a result, the phone interferes with the operation of the ADSL modem (frequent loss of connection). The phone makes noise when the ADSL modem is working.

Instead of a microfilter, you can use another ADSL splitter. At the same time, the second splitter has a connector MODEM not used. Connect the remaining two connectors as shown in Fig. 3.2.

Fig.3.2. Use of microfilters.

In general, if you look at the contract with the telephone operator, then in the contract it says - “one telephone line - one telephone set.”

If you have an office, then connect the line to a mini-PBX. If you have an apartment and you desperately need a telephone in each room, then connect the line to the DECT base, and then connect the radio handsets to each room.

Of course, one or two phones connected through a splitter do not put much load on the line, but five or more devices is already too much.

By connecting all these endless splitters, microfilters, telephones to the line, you increase the capacitive load on the line. Thus, you yourself are worsening the quality of telephony. A situation may even arise that, due to excessively increased capacitance, the calling signal will no longer pass through the line.

Also, the more connections, connectors, contacts, the less reliability.

How not to connect an ADSL splitter.

Electronics is the science of contacts. When needed, he is not there. When there is no dado, he is there (C)

The most common mistake is when connecting phones before the splitter.

Another option is to turn on the splitter somewhere, and turn on the ADSL modem somewhere. Telephones will be connected wherever possible. It’s clear that all this works “somehow.”

Sometimes they connect a telephone line to the splitter connector PHONE. Telephone sets are plugged into the splitter connector LINE. When turned on this way, telephones will work, but the ADSL modem will not work.

The strangest thing is that modem manufacturers indicate in the documentation the incorrect location of the connectors when connecting a splitter. The modem is drawn in every detail, but for some reason the splitter is drawn somehow. If you look at the photo of the ADSL splitter and look at the documentation, it turns out that the PHONE connector should be where the LINE connector is located.

See for yourself, the screenshots are taken from the documentation for the modems. The only exception is for the ZyXEL ISDN splitter in Fig. 9.1.

Fig.4.1-4.2. Connection options for ZyXEL splitters. Taken unchanged from the documentation.

Fig.4.3-4.4. Connection options for HUAWEI splitters. Taken unchanged from the documentation.

In the last picture they apparently tried to depict options for connecting microfilters.

ADSL splitter SIEMENS.

model S50010-D1010-A200-01.
Protection - two thermals (F1 and F2), arrester GD1 and C4.
Load capacity for telephony - 70nF
Feedthrough resistance - 12 Ohm
The output isolation for the ADSL modem is capacitive.
Filtration - system of bandpass/resonant transformers.
Very high quality RJ11 connectors with shielding protection.
The board is double-sided, fiberglass.

Fig.5.1. ADSL splitter circuit SIEMENS.

F1, F2 - 0.25A GD1 - CG2-350 R8 - 470 Ohm C1, C2 - 0.1uF 400V C4 - 33pF 1.6kV C5-C8,C10 - none C11,C15 - 10nF 630V C12 - 180pF 630V C13,C14 - 2.2nF 400V C16 - 150pF 630V C17-C19 - 6.8nF 400V C20 - 4.7nF 400V C21,C22 - 3.3nF 400V C23 - 22nF 1kV

The diagram of the model S50010-D1010-A200-03 is similar.
Transformers are made as a standard product. (as in network cards)
Winding transformers is more complex. There may be capacitors inside the assembly.
Load capacity for telephony - 50nF

Frequency response of the SIEMENS splitter.

Fig.5.2. Passage of LINE-POTS signal.

Fig.5.3. LINE-NT signal flow.

Just some HI-END

Splitters SIEMENS S50010-D1010-A200-01 and S50010-D1010-A200-03. The cases are the same, but...A200-03 has a smaller board (for S50010-D1010-A200-03 you can cut off the excess part of the case yourself).

Fig.5.4-5.5. Siemens splitters.

ADSL splitter ECI.

The ECI-TELECOM splitter circuit is more compact. There is no connection for ADSL. Protection is a single varistor. Load capacitance for telephony - 200nF Feedthrough resistance - 12 Ohms Fiberglass board, double-sided. Very high quality 6-pin RJ11 connectors. (ADSL connector - RJ45) The contacts in the LINE and PHONE connectors not used for telephony are connected. The splitter can be converted into SIEMENS by adding open-circuit SMD capacitors 0.1 - 0.06 µF x 250 - 400 Volts to the open circuit between the LINE and MODEM connectors. There is space on the board.

Fig.6. Splitter ECI-TELECOM.

ADSL splitter ZyXEL AS 6 EE.

Protection - varistor VR1. Load capacitance for telephony - 90nF Feedthrough resistance - 14 Ohms Output isolation for ADSL modem - no. Filtration - system of bandpass/resonant transformers. The fee is one-sided, getinaks. The main problem is loss of contact, poor-quality soldering of connectors and parts.

Fig.7.1 ZyXEL (PSTN) splitter circuit.

C1 - 56nF 400V C2-C4 - 33nF 400V Frequency response of the ZyXEL (PSTN) splitter (it is clear that it is useless to look at the passage of the LINE-ADSL signal:)

Fig.7.2. Passage of LINE-ADSL signal.

Fig.7.3. Passage of LINE-PHONE signal. (It is interesting to compare with SIEMENS).

Fig.7.4. Splitter from ZyXEL (PSTN).

Fig.7.5. Splitter from D-Link. ...or HUAWEI. I do not remember:).

Fig.7.6. This is also an ADSL splitter from D-Link. :).

ADSL MICROFILTER.

Fig.8.1. ADSL MICROFILTER.

The circuit is very similar to AVU scoop filters and UVO alarm filters. Only the dimensions of the microfilter are five times smaller. There is no pleasure in recording the frequency response. This is such a bastard...

Fig.8.1. The photo shows the AVU filter, ZyXEL microfilters, etc..

ADSL ISDN splitter.

Manufacturer unknown. I won’t go into too much detail, I’ll just say that the diagram is somewhat reminiscent of Fig. 6, only everything is kind of small, toy-like. The material, details and installation are reminiscent of the aforementioned ZyXEL. Accordingly, the same rake with quality and reliability.

Fig.9.1. ADSL ISDN splitter.

The ADSL and LINE connectors are connected directly, without any isolation, so there is no point in giving the frequency characteristics of the signal passage between these connectors.

Fig.9.2. Passage of LINE-PHONE signal..

As you can see, the signal weakening begins after 100 KHz.

In St. Petersburg, I have not seen a single glitch-free connection on lines with an AVU (only test connections for now).

On all such lines, when connecting ADSL over ISDN equipment, problems begin with the HF channel of the AVU. A terrible noise appears on the line when talking in the HF channel. Sometimes the ringing signal also does not go through. Still, ISDN and AVU are slightly different things. ISDN is digital, AVU seems to be based on amplitude modulation.

Obviously, the noise from the DMT channels of the ADSL spectrum affects the modulation of the HF channel of the AVU. :) If I'm wrong, please explain.

There is also the opposite problem. If there is simultaneously a subscriber connected via ADSL AnnexA and a subscriber on another pair of AVUs living in the telephone cable, then most likely the AVU of the subscriber connected via the HF channel will have noise in the line (audio frequency range.)

The worse the telephone cable, the lower the insulation resistance, the lower the coupling attenuation between pairs, the higher the likelihood of a problem.

SIEMENS splitters - quality and reliability. There has been an improvement in the performance of Dial-UP modems when connected via a SIEMENS splitter. (decrease in retrains, increase in average speed.) There is only one drawback - it is very large in size and price. On low-quality telephone lines, with some DSLAM and types of ADSL modems, slight HF noise (hiss) in the head frequency range is possible. If the RF noise is very strong, the splitter is connected correctly and replacing the splitter/modem with a different model does not help, then the cause of the noise is serious damage to the telephone cable. As an alternative to SIEMENS, you can use ECI-Telecom. SIEMEN and ECI-Telecom are not officially sold anywhere. If you find them, only used ones. Practice shows that their quality does not depend on time. ZyXEL and D-Link splitters are very compact, they are convenient to install in communication panels, boxes and inside PBXs. This is where their advantages end. I can’t say anything good about the other splitters/microfilters. What else: There is also a completely unsystematic problem. Namely, when connected via a miniPBX splitter SAMSUNG NX-308, LG, etc. After completing an incoming call, the PBX does not release the line. It can be treated by replacing the splitter (not always). It also helps to install a Busy Tone Detector after the splitter. http://www.npficon.ru/