The VoIP and Unified Communication industry is booming. The VoIP industry generated total revenue of $14.1 billion in the US in 2020 alone (IBISWorld, 2020). Instead of relying on the traditional phone system, businesses can save up to 75% when opting for VoIP. (BullsEye Telecom, 2019). Equipped with a capable device, good internet connectivity, and a compatible headset, businesses can use VoIP to reduce calling costs while increasing productivity. You may wonder how a software-based calling mechanism can manage to replace traditional telephone exchange, especially call-switching. This is where Softswitch comes into the picture.

What is Softswitch, and How is it classified?
Softswitch is the acronym of Software Switch, and it is used in VoIP core network to control calls and process media streams. It can route VoIP calls & traffic across carriers and enable services such as switching elements, VoIP billing, directory services, network signaling, etc. It is safe to state that a Softswitch is the backbone of all VoIP communications. Based on the scale of application, there are five major classes of Softswitch:

Class 1 – used for international gateways
Class 2 – used for interstate communications
Class 3 – used for intercity communications
Class 4 – used in enterprise-level communications
Class 5 – used for end-user communications

Most VoIP service providers offer class 4 and 5 Softswitch to route calls over different networks. However, both classes are different in terms of features and their working areas, and the choice is vital when choosing a VoIP development service.

What is Class 4 Softswitch?
When routing IP-IP calls to long-distance international locations using an IP network, class 4 Softswitch is used. A call initiated from a class 5 Softswitch in one location is transferred to the class 4 Softswitch of retail VoIP provider and then connected to the class 5 Softswitch at the other location. Class 4 Softswitch offers fewer features than class 5 Softswitch.

Concurrent calls
Protocol support & conversion
Intelligent calls routing
Secured firewall
Easy to use and simple interface

What is Class 5 Softswitch?
Class 5 Softswitch is routing large volumes of calls within a city, town, state, or country. VoIP providers, cell phone carriers, and PSTN carriers used to connect VoIP-enabled devices to each other. When making a call from your device, the call is connected to your provider’s Softswitch, and then the call is routed to the correct IP address, SIP address, and DID number.

call forwarding
call rules (find me/follow me/DND)
call transfer
call waiting
caller ID
conference calling
enhanced voicemail
in-network calling music
ring/hunt groups
videoconferencing support
virtual numbers.

Key Differences Between Class 4 & 5 Softswitch
As you may have realized, class 4 Softswitch is for routing calls over a long distance, while class 5 Softswitch focuses more on local call routing. However, the difference doesn’t end there. Both Softswitches are different on the following key avenues:

Call Traffic Volume & Type
Functionality-wise, concurrent calls from multiple class 5 Softswitches are redirected to a single class 4 Softswitch. So, class 4 Softswitches are built to handle large volumes of calls at the same time. Class 5 Softswitch deals with smaller call traffic.

Targeted users
Class 5 Softswitches are designed to work with both VoIP service providers and end-users. Class 4 Softswitches are made to serve wholesale VoIP solution providers, carriers, and Telco operators.

Routing Area
Class 4 can route a large number of long-distance VoIP calls across different networks and hence has a larger routing area. Class 5, on the other hand, routes SIP or IP address or a Direct Inward Dialing (DID) number of target users across a smaller area.

Intended Usage
As far as services are concerned, the Class 5 Switch serves as a handy retail solution. Besides, it also serves as an exchange in the PSTN, which is responsible for catering to the end-users and is located at the local telephone center. On the contrary, the Class 4 switch serves as a wholesale solution. It is a central office telephone exchange, which interconnects various local exchange carrier offices to establish communication for a long distance in PSTN.
Benefits of using Softswitch
By using Softswitches, organizations have observed the following benefits:

Scalable Solution: Softswitches are generally easy to scale up or down, depending on the network’s size, compared to regular switches. A VoIP Softswitch can be scaled with the company’s growth and be upgraded with a simple download.

Versatile: Routing, reporting, invoicing, and monitoring are all services that a VoIP Softswitch may accomplish. Softswitches may be integrated with other software to help businesses run more efficiently.

Accurate billing: Providers may adjust call rates and produce exact invoices for each of their clients using VoIP Softswitches. As a result, Softswitches free up time and resources that organizations may put toward their main activities.

Highly Cost-effective: Softswitches are extremely cost-effective since they do not require any additional hardware. The program is installed and upgraded in a virtual environment.

Wrapping Up
As you may have realized, there is no case of superiority when it comes to class 4 and 5 Softswitch. Each is pivotal for providing seamless communication between different enterprises across the country. VSPL specializes in creating custom VoIP desktops as well as offers hybrid Softswitch solutions.

Author's Bio: 

Author works as BDE at Vindaloo Softtech (VSPL) since 2016. Sandip has 10+ years of work experience in VoIP Software Development Industry. VSPL is VoIP software development and solutions provider that offers FreeSWITCH, Kamailio, OpenSIP, WebRTC and Asterisk Development.