It describes the advantages of IP telephony over conventional (analog) telephony. In this case, we are talking not only about asterisk, but about any IP telephony systems: both paid and free. Disadvantages of IP telephony see.

1. The main thing, of course, is cheapness. Compared to analog telephony, ip telephony [long-distance / international] costs a penny (and if there is enough direct communication between two subscribers / offices with each other, the subscription fee for telephone communication can be zero - provided that there is a connection via a computer network / Internet ).
2. Versatility: by ip telephony, you can (theoretically) connect any subscribers using a variety of protocols / technologies (for example, skype with an ip-phone, send sms to a subscriber from icq, etc.). In addition, of course, it is possible (through the appropriate equipment) to connect subscribers of analog, digital and IP telephony.
3. Flexibility:
   1. Call forwarding under various conditions, depending on the time of day, caller's number, no answer, and so on. Those. the subscriber can be constantly available [by his number on the PBX] for other subscribers, regardless of whether he is on site or away.
   2. Assigning "short" numbers for any subscribers.
   3. Integration with a computer and mobile phones: both a computer and a mobile (or landline) phone, smartphone / tablet, etc. can act as subscribers.
   4. Call logging: from recording the fact of a call from number to number and ending with the recording of ongoing conversations and / or listening to the conversation in real time.
   5. Connection to an unlimited number of analog and IP telephony operators, with automatic or manual [at the request of the subscriber] selection of the cheapest / high-quality operator, depending on the direction of communication / caller's number / time of day / moon phase, etc.
   6. Possibility of combining into one virtual telephone network any number of offices or points, each of which may have any number of telephones, with free calls within the entire virtual network [if there is a connection between all these points via a computer network or via the Internet].
   7. As part of 3.3, subscribers access to PBX from the Internet, which allows remote subscribers (outside the office, in another city or another country) to make and answer calls as if they were in the office (and for free, only the Internet is needed!).
4. Work with faxes. Although ip-telephony (in fact) does not improve, but rather even worsens the work with faxes (in the sense that less than% of faxes pass through ip telephony without problems), at the same time, work with faxes is simplified, since it becomes possible to send and receive faxes directly from the computer, without translating the document into paper form (and / or receive faxes by e-mail).
5. Additional features, usually not provided by analog telephony (or extremely expensive):
   1. Call from the site
   2. Voice mail messages can be transmitted to the subscriber digitally (for example, in the form of an audio file on an e-mail, a link on a website, etc.)
   3. Conference call with any number of participants
   4. Queues: the ability (mainly for call centers) to distribute a lot of incoming calls among a small number of operators, with notifications about the remaining waiting time, advertising / informational messages, greetings, and so on.
   5. Voice menu / auto attendant, which includes both a greeting and the ability to make a choice (including a voice one!) Of the desired department or specify the subscriber's number.
   6. Using PBX as an alarm clock, to-do / birthday reminder, calculator, directory of phone numbers, etc.
6. Mobility: unlike analog telephony, where the phone number is "tied" to a specific telephone socket, in ip telephony the binding goes (in particular) to the ip address, which means that employees can move from office to office, from building to building, from office to office within the same computer network, with the preservation of the number and without any additional PBX settings. In addition, the possibility of call forwarding (clause 3.1) allows any employee to work remotely (from home, another city or another country) just as if he was at his workplace.
7. Many PBXs (for example, asterisk) are completely free for any use (both home and commercial).
8. In the cheapest version, subscribers only need to have headphones and a microphone connected to a computer as equipment - many client software options are also free!
9. Access limitation:
   1. For internal subscribers: the ability to restrict / prohibit calls to certain directions of communication, or the choice for different groups of subscribers of different telecom operators, etc.
   2. For external subscribers: depending on the external subscriber's phone number, the prohibition of dialing numbers of certain departments, the possibility (or impossibility) of dialing an external (city / long-distance / international number) directly from the voice menu, etc.
   3. For any subscribers (optional) - restriction of access to certain PBX functions, for example, call forwarding, call recording, wiretapping of conversations in real time, and so on.
10. "Black list" of subscribers with the issuance of any message to them.
11. IP telephony is not limited to voice only. It can send text messages, display [for example, via jabber] the status of subscribers (away, talking, busy, ...), provide video communication and is quite capable of replacing tools such as skype (which, after the purchase by Microsoft, deteriorated the quality of communication, especially corporate) ...
12. The number of numbers on the PBX is unlimited, and the number of simultaneous conversations / calls supported by the PBX is limited only by the capacity of the installed equipment *.
13. Billing: starting from the statistics of calls (including local ones) and ending with the formation of invoices that you can issue to those who use your PBX for calls (for example, tenant organizations or even your employees).
14. Call interception, call parking.
15. Calling subscribers / clients according to the list with the issuance of a voice alert / notification, while it is possible to provide feedback (using the voice menu) and collect information about the results of the call.

* also depends on the PBX itself, for example, asterisk works stably up to 1000 simultaneous calls.

What is IP telephony?

The Internet is fundamentally changing the way we think about telephony and how we communicate. IP telephony is a technology that ties together the benefits of telephony and the Internet. Until recently, circuit-switched networks (telephone networks) and packet-switched networks (IP networks) existed almost independently of each other and were used for different purposes. Telephone networks were used only for the transmission of voice information, while IP networks were used for data transmission. IP telephony technology connects these networks through a device called a gateway.

Gateway is a device that connects telephone lines on one side and an IP network (for example, the Internet) on the other. The gateway serves as an interface between the user's audio transmission device (telephone, computer, etc.) and the Internet; it provides reception and transformation of data into a form convenient for sending over the Internet (and reverse transformation).

During a conversation, voice signals are converted into compressed data packets. These data packets are then sent over the Internet to the other party. When the data packets reach the destination, they are decoded into original voice signals.

How it all began?

Internet telephony uses the Internet to send audio messages between two or more computer users in real time. The very first Internet telephony software product that allows you to send voice messages over the network - VocalTec Internet Phone - was introduced by the Israeli company VocalTec in early 1995. For the first time, a user of a personal computer equipped with a sound card, microphone and connected to the Internet was able to conduct voice conversations with another same user, no matter how far from each other they were. Most of the software products from the same series, which appeared later, allow users to speak into the microphone and hear the interlocutor's answer through the speakers.

Before it was born, the new opportunity attracted worldwide attention. The technology has steadily improved and very quickly approached the point where voice communication became easy and continues to evolve. Many companies have presented similar programs. At the same time, in many systems, along with the ability to exchange voice messages, the ability to conduct correspondence, send files during a conversation, exchange graphic images and video images has been added.

Types of communication over an IP network

Computer - computer ... This is the earliest and easiest way to IP telephony. To organize the transmission of traffic, the user purchases the necessary equipment and software, and also pays the provider for the operation of the communication channel. The advantage of this option lies in the maximum cost savings. The disadvantage is the minimum quality of the connection.
Phone - phone ... The subscriber does not need any special equipment, only a regular telephone. Voice traffic is transmitted over an IP network, usually in a separate expensive section. The devices organizing the interaction are gateways docked, on the one hand, with the public switched telephone network, and on the other, with the IP network. Voice communication in this mode, in comparison with the computer - computer option, is more expensive, but its quality is much higher and it is more convenient to use it. The quality of communication is comparable to the quality of a regular telephone conversation, since the company uses dedicated communication channels. In order to use this service, you need to call the provider serving the gateway, enter the code and the number of the called subscriber from the telephone set and talk in the same way as with a regular telephone connection. All necessary routing operations will be performed by the gateway.

Computer - telephone ... The end user does not need any additional equipment. It is enough to have a phone with the possibility of tone dialing at hand. This is necessary so that, after calling the operator, enter your code in tone mode, and then the subscriber's actions are no different from the usual ones. Most modern telephones, including payphones and mobile phones, have this feature. If for some reason there is no such phone, then a beeper or, in extreme cases, a special program that can be downloaded from the Internet can handle the dialing function.

Web - phone ... Another new service is a call from a Web site, which allows you to make a call by selecting a link to the name of the called party from the Internet page or simply by dialing a subscriber phone number. This solution is aimed primarily at expanding the capabilities of e-commerce. A WEB-phone allows Internet users to talk directly, for example, with a sales representative or with a technical support specialist of the company of interest. Establishing a telephone connection occurs in the usual, familiar way of dialing a number or by simply clicking on a link, which is, for example, the name of the company, the name of the called subscriber, etc. on the Internet page. In this case, the user does not need a second phone line or an interruption to the Internet, only needs to download a small client software, which can usually be found on the same web page, and which is installed automatically. On the other hand, a Web phone allows company representatives to answer questions, display Web pages, and transmit necessary information, thereby improving the quality of services provided.

Advantages and disadvantages of IP telephony

The main advantage of IP-Telephony is the lower cost of long-distance and international calls in comparison with traditional telephony.
Convenience is another advantage. For some people, the number of which is constantly growing, it is simply more convenient to call from a computer than using a landline phone. The possibility is not excluded that in the future IP-telephony will completely replace wired telephony, just as CDs replaced magnetic cassettes, and were later replaced by MP3-players.

The main limiting factor on the path of large-scale implementation of IP-telephony is the lack of mechanisms in the IP protocol to ensure the guaranteed quality of services, which makes it not the most reliable transport for the transmission of voice traffic. IP itself does not guarantee the delivery of packets, as well as the time of their delivery, which causes problems such as "ragged voice" and simple dropouts in the conversation. Today these problems are being addressed: standards organizations are developing new protocols, manufacturers are releasing new equipment.
Another problem that manufacturers of Internet telephony systems have to solve is the lack of a single standard for programs that provide communication. Currently, communication via an IP network is only possible if the same systems are used on both sides of the connection being established. So, for example, the user of the VocalTec Internet Phone program cannot call the user of the FreeTel program and vice versa. This problem arose because the earliest Internet telephony programs used proprietary protocols to communicate with each other.

Video communication in computer networks

More recently, video communication was the domain of large corporations and science fiction films. Digital camcorders were too expensive and communication speeds left much to be desired. Now the situation has changed, but today video communication is a kind of luxury item, which does not detract from the convenience of this progressive type of interactive communication.
There are many programs for organizing video communication or video chat on the Internet, the most popular are the following:
* Skype
* ooVoo
* ICQ
* Мail.ru Agent
* Trillian
* Windows Live Messenger
* Yahoo! Messenger and others.

How to establish video communication?

The most important condition necessary for the implementation of video communication is the availability of an Internet access channel with sufficient bandwidth. The fact is that during a video session, not only voice data is transmitted, but also a video stream. Of course, before being sent to the Network, the transmitted information is compressed using special algorithms that provide multiple compression, however, despite this, the bandwidth requirements are still quite high. It is usually considered that in order to ensure high-quality voice communication via the Internet, the "width" of the access channel to the Network should be at least 64 Kbps; to ensure high-quality video communication, this figure will be at least twice as high.

Software issues
In addition to broadband Internet access, video communication requires special software. Such software can be an IM messenger like ICQ, Google Talk or any other program mentioned above that has a built-in video chat function. Unfortunately, the listed tools are incompatible with each other - the ICQ user will not be able to communicate with the Skype user. In principle, an ordinary Windows XP user can use the NetMeeting program included with this operating system.
It should also be noted that despite the large selection of programs for organizing video communication or video chat, however, not all of them are suitable for working in a local network, since they need a server and an Internet access channel to work. They were developed to organize communication with remote points, and not to work in a local area network. Firstly, not all networks have access to the Internet, and secondly, video communication through a remote server will create a fairly large stream of Internet traffic, which, as a rule, is paid. And in general, it is strange to contact a server located thousands of kilometers away in order to contact a neighbor behind the wall.
Of course, there are specialized packages and even hardware solutions for organizing video conferencing in a LAN, but their cost is too high for an ordinary user and they are primarily targeted at companies.

Hardware

To organize a video call you need:
*
* Sound card
* Microphone

The most popular means of "capturing" images transmitted over the Internet is a webcam. In addition to webcams, there are other tools for organizing video communication - videophones. The videophone is a completely independent device that does not require a connection to a computer. Such a gadget is connected to the TV via composite connectors; Internet communication is usually carried out using an Ethernet interface. You can make a "call" from a videophone both to the owner of a compatible videophone and to a computer with a webcam and Windows NetMeeting installed.
However, videophones are rather exotic devices aimed mainly at the corporate sector (this fact is reflected primarily in their price); therefore, traditional webcams are of the greatest interest to us.

When buying a webcam, you should pay attention to the version of the USB interface used. The USB 1.1 interface will provide video capture with parameters 640 x 480 pixels at 15 frames per second. USB 2.0 with higher bandwidth will allow you to get 30 or more frames per second.
It makes no sense to focus on the quantitative parameters of webcams - almost all of them have a resolution of 640 x 480 (recall that a resolution of 320 x 240 is quite enough for video conferencing), as well as a built-in microphone.

It is not expensive
The use of video communication is completely free, so those who wish to use video communication will not have to spend money to purchase this service; only broadband Internet access will be payable.
The one-time costs will come from the purchase of a webcam or videophone.
Owners of some laptop models do not have to spend money at all - many of them are equipped with built-in webcams.

Advantages and disadvantages of video calling

Among the advantages of computer video communication, one can mention the relatively low cost of operation in comparison with other existing communication systems, their multifunctionality, and comparative ease of use. In the process of work, the subscribers of video communication (video conference) generally see on the screens of their monitors the images of the interlocutor and their own, which is necessary for visual control of the established connection. The image is dynamically updated at a rate of up to 15-25 frames / s, depending on the speed (bandwidth) of the communication channel and the channel load. Participants for negotiations use miniature video cameras and microphones with fairly good characteristics.
The speech for transmission over the communication channel is digitized.
The main advantages of computer video communication are the ability to work together with documents and integrated information (text, graphics, images received from video cameras, as well as remote launch of software applications on the interlocutor's computer).
Thanks to video communication, the implementation of full-fledged remote offices is becoming more relevant than ever. Video communication with offices for meetings, operational meetings, conversations with individual employees will be in great demand. It often happens that an important fifteen-minute meeting requires many hours of standing in traffic jams. Video conferencing solves these problems, saving money and helping you get the most out of your work time. And what can we say about a situation when it is required to organize a meeting of people from different parts of our vast country - then only savings on transport costs can almost instantly recoup the costs of a video call session.
In addition to traditional business applications such as live meetings, telecom support (telecommuters and mobile users), distance learning and personnel certification, video can be effectively used in many other situations. For example, when recruiting (recruiting agencies, remote job interviews, etc.); remote medical and other consultation with experts; assessment of various types of damage and destruction (insurance companies); monitoring in case of emergencies and natural disasters; interaction of scientists during scientific research, etc.
By and large, video communication is necessary wherever efficiency is required in analyzing the situation and making a decision, as well as collaboration in remote access mode. This is an indispensable tool in the work of companies with an extensive network of branches. Modern video communication tools provide opportunities for collaboration with data and various applications, up to signing documents, and existing cryptographic protection tools allow you to preserve the confidentiality of the content of video communication sessions.

As such, video communication itself has no drawbacks. However, disadvantages appear as a result of the use of certain means for organizing video communication:
* high requirements for the bandwidth of communication channels;
* poor image quality;
* poor synchronization of picture and sound;
* long transmission delay, long reaction time when ordering viewing records;
* complexity of service and others.

Skype

Let's consider one of the most popular programs for organizing audio and video communication in computer networks - Skype.

Skype was founded in 2003 by Niklas Zennström and Janus Friis.

Skype is a free proprietary software that provides free encrypted voice communication over the Internet between computers (VoIP), as well as paid services for communication with subscribers of a regular telephone network.

It is possible to organize conference calls (up to 25 subscribers, including the initiator), transfer text messages and files, as well as video communication (currently, when using a standard client - up to two subscribers, and when using third-party plug-ins, their number is limited only by bandwidth channel ability).

Services provided by Skype

Paid services
SkypeOut
SkypeOut allows you to make outgoing calls to landlines and mobile phones in most countries of the world. Payment by the minute.
Calls within Russia
Calls to toll free numbers (such as +1 800 in the US) are free and can be used even by non-SkypeOut users.

SkypeIn
Allows you to receive phone calls from users of traditional telephone networks. In this case, the participant receives a telephone number. All incoming calls to this number will be sent to your Skype account, while with a positive SkypeOut score, calls can be forwarded to any phone number. As a bonus to the phone number, Skype provides an answering machine free of charge for the entire duration of the use of the number.

Skype Voicemail
An autoresponder that allows you to record incoming messages when the user is offline.

Free services
SkypeCast
Voice chats - allow a large number of Skype users to communicate at the same time, create rooms for communication of interests. On September 1, 2008, SkypeCast was discontinued.

XXI century - the century of new technologies, high speeds, a huge amount of information. Today, both in business and in everyday life, innovative solutions are required to optimize activities. One of them - IP-telephony - is a modern method of communication, which is currently actively replacing analog telephony. What are the advantages of such a means of organizing telephone networks and who needs it? Let's figure this out.

IP telephony: what it is and how the technology works

The development of Internet technologies served as an impetus for the emergence of IP telephony. In 1991, American researcher John Walker created the NetFone program, which allowed the exchange of voice messages over the Internet. This development, in fact, was the first VoIP phone. VoIP (Voice over IP) is a technology that allows you to “transmit voice over the Internet”. To connect analog telephone networks with Internet networks, special gateways are used to turn ordinary telephones into VoIP devices. An alternative can be a computer, mobile phone or tablet connected to the Internet with special software installed on them. If desired, you can also purchase SIP phones.

IP telephony services are in demand both in the office and at home. This type of communication makes it possible to send messages by fax, organize online conferences, and forward calls. In addition, the use of IP-telephony services can significantly reduce the cost of long-distance and international calls.

Benefits of Internet telephony

The first question that worries potential IP telephony users is the quality of communication. An important advantage of the technology is that the sound quality does not depend on the distance at which the interlocutors are located, which cannot be said about analog telephony. When using Internet telephony, there is no noise, echo or other unpleasant effects.

The second important advantage of IP telephony is the low cost of communication compared to analog. In particular, the cost of international and long distance calls is much lower, and calls within the corporate network are free - regardless of the geographical location of the company's offices. As for the price of IP-phones, it is quite comparable to the cost of analog devices. However, as we have already noted, from those you can end up in favor of installing software on the appropriate gadgets connected to the Internet.

Among others advantages Internet telephony is noted by:

• the possibility of a quick start for a business - almost instant installation of telephones in the office at low costs;
• reduction in the number of employees who were indispensable when using an analog PBX;
• mobility of employees: there is no binding to a telephone set, there is always the possibility of quickly setting up call forwarding to a mobile phone;
• the ability to program and configure IP telephony at a distance, without calling a specialist.

Consider possibilities provided by Internet telephony:

• Integration... IP telephony can be integrated with other communication solutions, for example, with the 1C program, with the company's website, with various Internet services and software.
• Multichannel number, thanks to which the company's clients do not need to wait for a long time for a connection. This number will never be busy! In addition, IP telephony providers provide call center services at very attractive prices.
• Voice menu(auto attendant) and smart forwarding.
• Organization possibility video communication, conducting video presentations.
• Access to any statistics within the framework of the use of telephone communications, control and quotas for out-of-service calls and any calls from corporate numbers.
• Voicemail, Email Fax, Blacklist, Reporting and much more.

According to the International Telecommunication Union (ITU / ITU), Russia is among the leading countries in terms of the level of telephony - in 6th place. And according to the level of Internet penetration - in 71st place. 55 out of 100 people use the Internet.

What equipment is needed to organize IP telephony in the office and at home?

As we noted earlier, in order to organize IP-telephony in an office or at home, first of all, it is necessary to have an Internet connection. Moreover, the data transfer rate must be at least 512 Kbps in both directions. In this case, you can use analog telephone ... To do this, you need to connect a special adapter (IP gateway) to it, thanks to which an ordinary phone will turn into a device that works over the Internet. IP gateways are single-channel (for home and small offices) and multi-channel (for large companies).

You can organize IP telephony and by purchasing a telephone SIP devices (manufactured by AddPac, Cisco, D-Link, QTECH, RAD Data Communications).

And the third method is the so-called IP soft phone, which is special software (for example, YouMagic) installed on a computer, tablet, smartphone.

Thus, Internet telephony can be carried out as follows:

1. "Telephone-telephone"... Analog telephones connected to the IP gateway transmit voice signals, which are converted into compressed data packets during the transition to the Network. These packets are sent over the Internet to the addressee and at the output are again decoded into analog voice signals. In this case, a full-duplex conversation takes place (when both interlocutors can speak at the same time).
2. "Computer phone"... Those wishing to organize IP-telephony can purchase special software from the provider, with the help of which it will be possible to make calls. This software is installed on any device connected to the Internet - a smartphone, tablet, computer. It does not matter what device the interlocutor uses - analog, SIP or mobile phone.
3. "WEB-phone"... In this way, you can call directly from your browser. For example, a business owner can organize reception of calls on his website using a special click2Dial script. In order to call the operator, the client only needs to click on a special button on the website.

IP telephony providers: who is who

World telecommunications companies are now massively abandoning outdated classical telephony, trying to interest users in modern convenient Internet telephony technologies. Analog telephony is gradually being squeezed out of the market, however, the number of implemented and used analog telephony systems is still significant. Nevertheless, the number of fixed telephones in Russia is steadily decreasing: 40.1 million in 2008 against 36.6 million in 2013. At the end of 2015, the total volume of analogue telephone services amounted to 221.7 billion rubles, and mobile services - 644.9 billion rubles. For comparison: in 2014, the volume of the IP telephony market in Russia was in the region of 17.1 billion rubles. In general, at the moment in Russia there are about 30 million users of IP-telephony.

In Russia, the first companies providing voice communication services over IP-protocol appeared about 20 years ago. To date, the IP telephony market has more than 500 licensed members. The turnover of IP-services in Russia per year is more than $ 65,000,000. More than half of the market is made up of long-distance and international communication services. Among the leaders are the companies "Interregional TransitTelecom" ("MTT"), "Rostelecom", "TTK".

Analysts believe that the growth factors in the Internet telephony market in Russia are the increase in the number of users of fixed and mobile Internet access, the growth in the activity of IP-providers and the persistence of high tariffs for long-distance communications.

When choosing an IP telephony provider, experts recommend paying attention to the following factors:

• Security. The operator has a reliable mechanism to prevent telephone fraud.
• The operator has its own telecommunications network.
• Competitive price. Compare the rates of different operators and choose the most acceptable: it is not recommended for business to choose too low rates for calls, as large operators offer reduced quality VoIP resellers for a lower price.
• Check if this operator can arrange "porting" of existing analog numbers.

Tariffs: price matters

The cost of connecting to IP-telephony will depend on the selected type of communication organization. Thus, the purchase of an IP-gateway will cost 4,000-15,000 rubles. The purchase of a SIP-device will result in a similar amount: 4000-10,000 rubles. Plus, you need to take into account the cost of accessing the Network and equipment maintenance. The provider you contact for assistance in connecting equipment or setting up a service will charge you only for outgoing calls directly.

The advantages of IP-telephony are especially clearly visible on the example of long-distance and international tariffs. Consider the average prices. So, will a call from Moscow to St. Petersburg cost 60 kopecks per minute, to Yekaterinburg? 61 kopecks / min., To Irkutsk - 1 RUB / min., To Vladivostok - 1.5 RUB / min.

The transition to IP-telephony significantly reduces the costs of international communications. If we talk about the CIS countries, a call to Belarus will cost 45.43 rubles / min, to Kazakhstan - 1.2 rubles / min. The cost of a call to the United States ranges from one and a half rubles per minute on average. You can call Europe at similar rates: Germany - 0.7 rubles / min, France - 0.8 rubles / min, Italy - 0.4 rubles / min. A call to China will cost 1 ruble per minute of communication.

Thus, using the services of IP-telephony, you have the opportunity to make a phone call without turning to city telephone networks or to cellular communications, while using advanced functionality, as well as reducing communication costs.

Recently, an increasing number of subscribers, both private and corporate, are trying to use VoIP telephony services. This is due to a number of technological advantages that IP telephony offers over conventional wired communication. When IP telephony technology has already been implemented in the office or as a home solution, any user is faced with the question: what is better to choose: a softphone or a hardware IP phone? We will try to give a number of tips and recommendations for the choice of communication terminal devices, as well as identify the pros and cons of each of these solutions.

So, we will start our research of the market of devices for VoIP telephony directly from softphones. Softphone (software telephone) is actually a software product that allows the user to make calls over the Internet or through any IP network. A softphone does not need additional hardware solutions, except perhaps a computer headset or a webcam to make video calls. Softphone software is usually developed based on the open communication protocols SIP or H.323. But there are certain companies that have developed their softphones based on specialized closed communication protocols, for example, such as Skype, ICQ or Mail.ru Agent.

A softphone is essentially a program that replaces your hardware IP phone on your computer. As we already wrote above, for the softphone to work properly, you need a telephone headset (in extreme cases, headphones and an external microphone). The advantages of a softphone are as follows, firstly, it is an advanced interface that cannot be limited to a small phone screen. Secondly, it is a large phone book, which is physically impossible to implement on a hardware phone. Also, to the advantages of softphones, you can add the function of your online status, the ability to send text messages and faxes, and video calls. Softphones can be both paid and free. The most common programs for IP telephony are 3CX, iSoftphone, Bria, ZoiPer, ShoreTel Sky Softphone, Octophone and others. It would seem that software clients for IP telephony are an ideal solution for any subscriber, but as in all purely software solutions, there are pitfalls. What disadvantages can we find in softphones?

I would also like to note the fact that, like any software, a softphone can "hang", "not boot", "require updates via the Internet", "give an error", etc. Also, the quality of work of such programs directly depends on the power of your computer and the optimal setting of the operating system. For example, if you are currently processing video, working with graphics programs or performing other resource-intensive tasks, and you suddenly received a call on a softphone, then the connection quality may turn out to be simply terrible or unstable, the sound will periodically disappear. In the case of a home subscriber, you can “close your eyes” to these shortcomings, given the availability, simplicity and even sometimes free of charge of such software solutions. If you are an office subscriber, then it is still optimal for you to use a hardware VoIP solution.

An IP phone is a hardware device for communicating with remote subscribers that provides voice communication over the Internet or corporate local area networks. Externally, devices for VoIP communication look like quite ordinary telephone sets. They have a handset, dial pad, LCD display, and an interface for connecting to IP networks. The work of such a phone is implemented using the SIP or H.323 protocols.

In IP phones, as a rule, the following functionality is implemented: voice mail, speakerphone, auto redial, call transfer and call forwarding options, call hold. A convenient telephone headset can also be purchased for such a device. An advanced IP device can also support a number of additional options, such as various types of call transfer ("blind" transfer, transfer with notification), the inclusion of background music on hold (music on hold) and conferences with several subscribers on the phone.

The main advantage of an IP phone over a softphone is that it is still an independent hardware device that works autonomously, and is not loaded as software on a computer. This means that even if your computer is not turned on at the moment, boots up, does not work at all, or the operating system is being reinstalled on it, you can still fully use VoIP communication at 100%. Yes, to purchase an IP-phone, you need to allocate funds (and this is the main drawback of IP devices), it is also possible to buy a professional headset for operators, for example. But in the corporate sector, as well as in medium or even small businesses, these investments will pay off. In business, counting on the reliability of software such as a softphone, especially a free one, is extremely imprudent. Softphones were created primarily for the home user or for the very small business sector. Another factor to be noted is the security and confidentiality of your negotiations. After all, it is much easier for hackers to hack the program and intercept all your voice traffic when using softphones than when using hardware IP phones.

The problem of information security must be given special attention before choosing a communication device for IP-telephony. For example, in messages about hacks or leaks of confidential information or passwords, such well-known VoIP programs as Skype, as well as the ZoiPer softphone and other similar programs, have repeatedly appeared. The fact is that your information, for example passwords, in such software solutions can be stored in a common database either on the servers of the softphone developer company, or in the "cloud". The company that developed this software product is responsible for its security, and you, in the event of a data leak to cybercriminals, will not be able to influence this negative process in any way. After all, you do not know how reliably the password database is protected in this company. In the case of a hardware IP phone, detecting vulnerabilities, hacking and intercepting your communications will require more resources and skills from hackers than breaking a computer program. Therefore, in case of special confidentiality of your conversations, we recommend using only IP phones from trusted and reliable manufacturers, preferably with support for the SRTP protocol (protocol for encrypting voice traffic).

What is VoIP and IP Telephony?

IP telephony, VOIP telephony, or SIP telephony - telephone and video communication over the Internet and other computer networks (for example, the network in your office). What is the difference between IP, VOIP and SIP? IP telephony (pronounced IP telephony) is a generic name for the technology of telephony over IP (Internet Protocol - literally "Internet Protocol"). VoIP (pronounced as voip, Voice over IP - literally "voice over the Internet protocol") is a more private name for the technology, includes all options for voice and video transmission over the network (including watching movies online, video surveillance, webinars, etc.). Essentially, IP telephony and VoIP telephony are the same thing. When the technology was invented, various communication protocols began to be invented, the most popular and reliable of which was SIP (Session Initiation Protocol). To summarize: IP telephony, or VoIP telephony, is a technology for telephony through computer networks, and SIP is a protocol that ensures the reliable operation of this technology.

Benefits of IP telephony

IP telephony is convenient and easy to use, both in the office and at home. The advantages of IP telephony are obvious. With the modern development of technologies and data transfer rates, the quality of communication is comparable to traditional telephony, and at the same time there are beneficial advantages:

• You can connect both a direct city number and a free "8-800"

• Low cost compared to traditional telephony

• No georeferenced:

• You can move to another address, while your phone number is saved

• You can receive calls to a landline phone while you are anywhere, for example, on a business trip, at home or in the country

• Working from home is not a problem - they will receive calls from the office phone while at home.

• A large branch network is easy! All calls to the office are easily forwarded to any of your branch, office, or store.

• The number of employees has grown, or the number of branches has grown - the issue of providing communications is resolved in minutes.

• You can receive calls to the city number of one city, while in another, or even - to the local number of any other country, while in your city.

• Modern technologies for organizing business: VoIP telephony is primarily a software solution, which means it can be easily changed to suit your needs, in addition, there are many ready-made solutions. Here are just a few of them:

• Greeting and Voice Response (IVR)

• Waiting queues

• Blacklists

• Dialogue forms (behavior patterns) for agents during a call

• Assigning subscribers to certain operators

• Formation of a customer base

• Call scheduling

• Integration with CRM systems and any databases

• Telemarketing

What do you need to start using VoIP telephony?

So what we need:

1. Choose a SIP provider and get a phone number
2. Select an office PBX:

• Virtual (software) PBX on your office server. As a server, both your office server and any computer connected to the Internet can be suitable. PBX software can be paid and free. Free virtual PBXs, as a rule, require special knowledge, long setup and maintenance. We have developed our own free PBX -. What are the differences between the main free software PBX you can see in our.

• A virtual office PBX on a remote server with Internet access is a paid service, usually paid by subscription, the cost depends on the number of internal phone numbers.

Let's look at a simple scheme for organizing an office PBX on your own server with a virtual PBX Komunikator installed.

What additional equipment might I need?

It all depends on your tasks and the size of your budget. Various options are possible:

• Use an ordinary traditional telephone. But in this case, you need to buy an analog adapter separately, or as it is also called (a device that converts a SIP signal for talking on a traditional phone).
• SIP phone - a telephone set ready to work with IP telephony. There are such phones and.
• Smartphone, or tablet computer on the Android operating system, or IOS (IPhone and iPad) with the application installed.
• Computer - any office computer with installed software (