IP-telephony

• by using IP-telephony you automatically reduce costs on communication because price on IP-telephony in all directions twice as small as usual telephony and communication inside IP Comtube network is free of payment!
• use IP-telephony if there is absence of local telephone lines;
• IP-telephony makes you responsive, now you are not confined to local operators of communications.

• you may start to use IP-telephony just now, you need to make quick registration and refill balance by any convenient way on page «Pay»;
• you may call on page «Main page - Phone» (you do not need to install programs, you need only microphone and earpieces or speakers);
• you also may choose and set up any other way of calls through IP-telephony from page «Settings – IP-telephony».

• free communication all over the world (inside SIP Comtube network);
• considerable saving on national and international calls;
• increase the quantity of telephone channels without any payment (get multichannel phone);
• free SIP number in Comtube network or direct virtual number in any city;
• usage of your ANI – automatic number identification (Caller ID) for outgoing traffic;
• convenient and understandable interface;
• absolute confidentiality.

• call planning;
• integration of service under your aims. All enquiries please send on: support@comtube.com.

IP-telephony, VoIP, SIP, Internet-telephony – all these appellations are referred to one way of communication. Let’s see it in more details:

• Internet— internetwork;
• IP (derives from «Internet Protocol») — Internet Protocol;
• VoIP (derives from «Voice over IP») — voice through IP;
• SIP (derives from «Session Initiation Protocol») — protocol of session’s establishment (or data transfer protocol).

So, IP-telephony is a type of communication which provides signal transmission (for example: voice) in world internet network or any other (local) IP-networks. Voice packets are preliminary digitized and transferred through communication channel as usual in tabloid form (depending on coder) in order to reduce the volume of passed information by increasing the quality of communication.

Every user who has access to internet may use IP-telephony but everybody will have different quality of communication. Internet network is a system of communication channels of different internet operators (joined each other) and quality of IP-telephony depends on internet you use and mostly depends on communication channels which your provider (operator) of VoIP-telephony uses. Circumstantially it depends on equipment («hardware») of provider and user but mostly depends on quality of internet channel from provider to user. Internet provider may say about high quality of communication up to 30 Мb/s, but in result «packets» of IP-telephony may be blocked or be in bottom priority of passing through operators’ networks.

In case of communication’s deterioration (reveal: echo, strays, voice distortion of talker or voice delay) you should do a simple command PING, which allows to see who has a problem.

PING (derives from «Packet InterNet Grouper») — is a duration of time when a signal sent from one widget comes to another one. It is measured by milliseconds (msec). The time of ping depends on speed and occupancy of communication channels over a distance of one widget to another one. Also PING is a support program on each computer. To run this program in Windows (Menu Start – Line of command): ping , where: , domain of operator’s website (for example, in order to verify the website of operator Comtube you need to write: ping comtube.com). The maximum allowable delay until 50 msec (the less delay, the better), in case the delay is more you can correct it only unfortunately by changing your provider as a supplier of your internet.

There are a lot of ways of calls through IP-telephony; everything depends on tasks and budget of customer. You may use IP-telephony without any equipment and downloaded IP soft phone; you just need only microphone and earphones (flash-telephone). If you need telephone for outgoing and incoming calls, for example, at home, you may buy a standard SIP adapter (VoIP gateway) from 2000 rubles (where internet channel is connected from one side and usual phone line from another side) and connect to Plain old telephone service. It is possible to match a standard IP telephone for office (from 3000 rubles), IP adapter (gateway service for 2-16 lines) or full IP АТS as automatic telephone station (which provides up to 100 simultaneous connections).

You may see all the ways of connection and match appropriate one for you in division «Settings - IP-telephony».