With VoIP technology booming in the technical era of the digital world, the word which speaks loud about its development and services is VoIP Switch. Also known with a similar name Softswitch that is a software switch it provides a platform to deploy VoIP services across wide range. It can be thought of as a VoIP server that is affluent in IP PBX call features. It is a software that connects telephones calls from one line to another and dominates in handling IP phone calls.
Diving deeper into the technological aspect of Softswitches, it plays different and crucial roles. These includes traffic controlling functions supportability, supports SIP registration functionality, and provide network services that is responsible for accepting , storing and distributing presence information etc. Traffic controlling by softswitch can be done through back to back user agent. In this when a client sends a SIP message, softswitch receives it and regenerates the message which encompasses modified headers and body of the message. And then this message is transferred to the destination. It works like an isthmus between User Agent Server (UAS) and User Agent Client (UAC).
The VoIP Switch registrar supports SIP registration functionality in a way that it connects clients from dynamic IP addresses. When a client requests for registration VoIP registrar that is a SIP server stores information in its local database. Softswitch supports TCP, UDP, TLS protocols and provide presence framework that is responsible for managing the presence information of the current user.
VoIP Switches can be classified as two major types of Softswitches – Class 4 and Class 5. Plethora of calls needs to be routed and this is carried out majorly by the Class 4 softswitch which is used to transit VoIP traffic between the carriers. Rate of calls, average call routing time, number of concurrent calls transcoding, protocol support and conversion are some of the features and functions of Class softswitches. Characteristics of Class 5 softswitches may include calling card platform, authorization, call centre services, IP PBX features etc. Therefore the Class 5 softswitches serves the purpose of working with the end users. At the end user site a softswitch is connected to various devices via TCP/IP network protocols. Various devices may include ATA (Analog Telephone Adapters) or IAD (Integrated Access Device) or eMTA (embedded Multimedia Terminal Adapters).
As softswitches are being famous many telecommunication networks rely on several combinations of VoIP Switches engaging enormous number of people.