End to end working of VoIP Call

VoIP Call

VoIP Call is the most useful thing in today’s world. Due to VoIP Technology, the present day telecommunication is much faster and user-friendly than the previous generations.

VoIP Call is undoubtedly the best and the cheapest means of telecommunication. It is the product of VoIP Technology. Starting its journey in the late 20th century, VoIP Technology is the latest advancement made in the field of telecommunication. VoIP is a form of internet telephony. It consists of a set of end-to-end elements, recommendations and protocols for managing the transmission of voice packets using IP. The 3 main elements that the VoIP system comprises of are: the sender, the IP network and the receiver. In today’s world VoIP is one of the most important services in the communication network. And it also demands strict QoS levels and real-time packet delivery.


Components of a VoIP System

The necessary components of a VoIP system that makes VoIP calling possible are a combination of various software and hardware.

Here is the list of the required items:


IP Devices

The most basic of all necessary item is a device with internet access to make the call. While the traditional IP Phone similar to regular landlines, may require an Ethernet Jack to connect to the network, devices like mobile phones do not need any such additional attachments. Internet connection from WIFI or cellular service is enough to make VoIP Phone calls. Computers, laptops and similar devices are also compatible with making VoIP Calls with an internet connection.


Media Gateways

The media gateway connects the IP network to the PSTN and allows those 2 networks to connect. For PSTN, gateways handle not only IP signalling functions but also support local exchange. Whereas for VoIP, gateways handle a wide variety of traffic. To know more about VoIP Gateway check here: Important Facts of VoIP Gateway you Need to Know



Softswitch controls the voice or data traffic. For this purpose, it signals the media gateways that transport the traffic. Softswitch uses established protocol and ensures that the information is communicated between the gateways. While Softswitch is of minimal concern for an end user, it is of prime importance for a VoIP Service Provider. To know more about Softswitch check here: Importance of Softswitch in VoIP Business



IP PBX includes a lot more functionalities than a traditional PBX. Its main purpose is switching calls between VoIP users and users on local lines while allowing all users to share a certain number of external phone lines.



Types of VoIP Call

There are 3 ways to make a VoIP Call.


Analog Telephone Adapter (ATA)

Using the device ATA is one of the common ways for making a VoIP Call. This device allows one to connect a standard phone to a computer or to an internet connection, for use with VoIP. The analogue digital converter or ATA converts the analogue signal from one’s traditional phone to digital data for transmission over the internet. An alternative to this is softphone. It is a client software that loads the VoIP Service onto the desktop or laptop.


IP Phones

IP Phones are similar to normal phones in their appearance. However, instead of the standard phone connector, they have an Ethernet connector. In addition to this, IP Phones have all the necessary hardware and software to handle IP Calls. And hence, they can connect to routes directly for accessing internet connection.


Computer to Computer

Software, microphone, speaker and internet connection is required to make a computer-to-computer VoIP Call. This is the easiest way to make a VoIP Call. And apart from the cost of the internet service, there are no extra charges for this type of call.




VoIP Call

The Packet-switched Network

The place where VoIP Calls differ from the traditional calls is its use of the network. While traditional calls use the circuit-based network, VoIP Calls use the packet switched network. In the packet switched network, the terminal splits up the information into blocks of moderate size called packets. These autonomous packets are capable of moving on the network as they have a header containing the source and the destination addresses. Thereafter leaving the source, the packet goes to the first node in this communication network.


VoIP Call Transmission

An alternate term for nodes is routers. The router examines the header on receiving the packet. It then forwards the packet to the next appropriate routes. This process of “store and forward” goes on through all the routers of the path until the packet reaches its destination, unless it is lost. Upon reaching the destination, the terminal at that point removes the header and obtains the actual data which originated at the source.

Therefore, the benefit of a packet switched network is that in this transmission, resources are allocated without sharing. On the downside multiplexing of different connection on the same resource may cause delays or packet loss. In conclusion, considering all the pros and cons, VoIP calls still stand as the better options for all calling purposes.

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