Understanding Voice Over Internet Protocol (VOIP)

VoIP stands for Voice over internet Protocol. It is a technology for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. The VoIP works better than the traditional digital phone.

For VoIP to work you need a VoIP capable device which can be:

· An iPhone with a soft phone configured to register to a SIP server.

· An IP handset which can be registered to an IPBX ( Internet Protocol Private Branch Exchange), as an extension, or to a public sip server.

· IPBX and router and VoIP phones and a reliable internet. You have to configure all things mentioned above.

An IPBX is a private branch exchange telephone switching system within an enterprise that switches calls between VoIP users on local lines i.e extensions while allowing all users to share a common number allocated to that enterprise by the SIP server providers. The sip line can be configured with multiple concurrent calls. The typical IP PBX can also switch calls between a VoIP user and a traditional telephone user, or between two traditional telephone users in the same way that a conventional analog PBX does.

For VoIP to work, this is facilitated by network convergence, allowing both data and voice traffic. One of the main advantages of an IP PBX is that it employs converged data and voice networks. This means that it allows Internet access, as well as VoIP communications. Some IP PBXs depending on the physical hardware added on them can integrate traditional analog telephone lines. This provides flexibility as an enterprise grows and can also reduce long-term operation and maintenance costs.

A router is a networking device that forwards data packets between computer networks. Routers perform the traffic directing functions on the Internet. An additional advantage of VOIP is that it allows multiple concurrent calls depending on the customer’s requirements.

A VoIP phone or an IP handset combines both hardware and software to enable the IP phone to use voice over IP (VoIP) technology to send and receive phone calls over an IP network. The phone converts analog telephony audio into a digital format that can be transmitted over the internet and converts incoming digital phone signals from the internet to standard telephone audio.

Advantages of VoIP phones:

· Mobile

· Scalable

· Organizations can reduce calling costs by switching to VoIP services

· International calls, as VoIP phone calls are charged at the local rate of the call’s destination.

· Softphones also provide increased mobility, as the clients are not tied to physical locations like they would be with hard-wired phones.

Disadvantages:

· Needs reliable internet

· If an organization has a power or internet outage, users cannot make calls from their VoIP phones.

How does a VoIP phone work?

Some VoIP phones require A/C adapters for power, while others use Power over Ethernet (PoE). PoE uses an Ethernet cable instead of an A/C adapter and removes the need for separate power and data cables.

Several networking components are required to make VoIP phones work. Phones are assigned IP addresses through the Dynamic Host Configuration Protocol (DHCP), which automatically configures the network and the VoIP parameters. A domain name system (DNS) tracks the IP addresses to enable devices, such as IP phones, to connect to each other. VoIP phones require a number of protocols to facilitate the delivery of voice communications over the internet. H.323 is the most commonly used VoIP protocol that supports audio, videos and data communications across IP networks. It provides several VoIP functions, including bandwidth management and call control.

Traditional analog phones may also be converted into IP phones by connecting to an analog telephone adapter (ATA). Analog phones can be converted by plugging the Ethernet network jack into the ATA, which then connects to the phone. The analog phone will connect to the internet rather than the PSTN, and it will appear to the phone system as a VoIP phone. Session initiation protocol (SIP) is a signaling protocol that sets up VoIP connections.

Now you have an overall understanding of Voice Over Internet Protocol.