The VoIP broadband phone technology uses the packet switching abilities of the Internet in providing phone services. Compared to circuit switching, VoIP has provided several advantages. In packet switching, several phone calls can occupy the same number of space which is only occupied by one phone call in circuit-switched networks.

Take for instance, if you are making a 10-minute call from PSTN, it would also consumed a full ten minutes transmission time with 128kbps rate. But with VoIP, a 10-minute call is equivalent only to a 3.5 minutes transmission time with a 64 kbps rate. Therefore it allows you to extend your call time to another 3.5 minutes to consume the entire 128 kbps or accept other calls at the same time. This estimate reveals that 3 or 4 calls can still fit in the remaining spaces utilized by one call in the traditional system. The data compression can reduce further the size of every call.

Packet switching incorporated to VoIP works in this manner:

1. ATA accepts the signals send by the receiver after the user picked it up to answer. ATA is the most common and simplest way of service using the Analog Telephone Adaptor device which converts analog signals to digital signals. It allows standard phone connection to your computer or internet connection for VoIP use. The converted analog signals are transmitted on the internet.

2. Dial tones will then be sent by ATA to let the person know that there is an internet connection.

3. The person can now dial the telephone number of another party he/she wants to talk with. The ATA will convert the tones to digital data and store it temporarily.

4. The telephone number is sent to the call processor of the VoIP Company as a request form to ensure that the format of the data is valid.

5. Call processor will determine the person whom the person is calling. This is a hardware piece capable of running a mapping or database program (soft switch). Soft switches know the network endpoints, phone numbers associated with the endpoints, and current assigned IP addresses on those endpoints.

Soft switches contain the user's database and phone numbers. If ever it does not have the needed information, the request is handed over to several soft switches until the answers to the request are found. Once the user is found, the soft switch also locates the device latest IP address similar to the requests. This relevant information will be sent back to the IP phone or softphone allowing data exchange among two endpoints.

The translation of phone numbers to IP addresses happens through a soft switch which connects two devices on either way. So, if one end is doing the call, the signal is sent to another end through ATA making the telephone ring. Soft switches should work in tandem with the network devices in making VoIP possible.

6. If the person picks up the receiver to answer, then the sessions between the two computers is established. Each system will know that data packets from other system are expected to arrive. The typical Internet infrastructure will handle the call like e-mails or web pages. However, the protocols used by both systems must be the same for them to communicate. Two channels is implemented, one for the direction and the other is for the session.

7. There is an allocated time for conversation wherein packet transmission occurs between the two computers. These packets are translated by ATA into digital signals after receiving it and then convert it again into audio analog signal to be heard. The ATA also keeps an open circuit between itself and the analog phone as it forwards the packets to IP hosts on another end.

8. The receiver will hang up when the conversation is finished. This will close the circuit between the ATA and the phone.

9. The soft switch will receive a signal from the ATA informing it to terminate the session. Packet switching let the data networks understands how technology works. The abilities of how computer communicates are immediately gained by telephone networks.

Compared to any other emerging technology, VoIP has provided essential advantages and most developers will still keep on refining it until it replaces the existing phone systems worldwide.

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