04 Aug 2023


If you want to upgrade your business phone system, you may have come across the terms VoIP and SIP Trunking in the telecom industry. Instead of using traditional phone lines, these are two technologies that allow you to make and receive voice calls over the internet. But what are VoIP and SIP Trunking, how do they work, and how do they differ from each other? In this article, we will answer these questions and help you decide which one is best for your business in the telecom industry.

What is a VoIP (Voice Over Internet Protocol)

VoIP stands for Voice over Internet Protocol. It is a technology that converts your voice into digital data packets, which are then sent over the internet to the person you are calling, where they are converted back into sound.

Benefits of VoIP

VoIP has many benefits over traditional phone systems, such as:

1. Cost savings

VoIP calls are usually cheaper than regular ones, especially for long-distance and international calls. You also don’t need to pay for separate phone lines or equipment for VoIP, as you can use your existing internet connection and devices.

2. Quality improvement

VoIP calls can have better sound quality than regular phone calls, as long as you have a good internet connection and enough bandwidth. You can also enjoy features like HD voice, noise cancellation, and echo suppression.

3. Feature enhancement

VoIP offers many features that traditional phone systems don’t, such as voicemail transcription, call recording, call forwarding, caller ID, conferencing, video calling, and more. You can also integrate VoIP with other applications and devices, such as email, CRM, mobile phones, etc.

SIP Trunking: Connecting your phone system to the internet or the PSTN

SIP Trunking stands for Session Initiation Protocol Trunking. It is a protocol that connects your IP PBX (a device that manages your phone system) to the internet or the public switched telephone network (PSTN) via a SIP provider (a company that offers SIP services). SIP Trunking allows you to use your existing IP PBX system to make and receive VoIP calls without needing a separate phone line or equipment. SIP Trunking also allows you to transfer not only voice data but also multimedia data, such as video, text messages, fax, etc.

Benefits of SIP Trunking

There are many benefits of SIP Trunking than traditional phone systems, such as:

1. Scalability

SIP Trunking allows you to add or remove phone lines or numbers as needed without having to install new hardware or wiring. You can also adjust your bandwidth usage according to your demand.

2. Flexibility

SIP Trunking allows you to use any device that supports SIP (such as desk phones, mobile phones, and laptops) to make and receive calls from anywhere with an internet connection. You can also use multiple devices with the same number or extension.

3. Reliability

SIP Trunking offers redundancy and failover options in case of network outages or disasters. You can route your calls to backup servers or locations automatically or manually.

4. Cost-effectiveness

SIP Trunking can reduce your phone bills by eliminating the need for separate phone lines or equipment. You can also save money on long-distance and international calls by using the internet instead of the PSTN.

Understanding the differences between VoIP and SIP Trunking

VoIP (Voice over Internet Protocol) and SIP Trunking are both essential components of modern communication, but they serve distinct purposes in the realm of digital connectivity. Understanding their differences is very necessary for businesses seeking the most effective communication solutions.

1. Technology and functionality


VoIP enables voice calls over the internet, converting analogue voice signals into digital data packets that are transmitted over IP networks.

SIP Trunking

SIP (Session Initiation Protocol) trunking is a method used to connect SIP-enabled devices (such as IP-PBX systems) to the internet, allowing them to make and receive VoIP calls.

2. Data Transfer


It is primarily limited to transferring voice data over the internet, allowing users to make phone calls using IP networks.

SIP Trunking

In addition to voice, SIP trunking has the ability to transfer packets of multimedia data, which can include voice, video, text messages, and even fax transmissions.

3. Service support


It mainly supports voice communication, allowing users to make calls between IP-enabled devices, often referred to as VoIP calls.

SIP Trunking

It supports a broader range of services, including voice, video, instant messaging, and fax. This versatility allows businesses to have more comprehensive unified communication solutions.

How VoIP differs from SIP Trunking?

It's essential to note that VoIP is a technology used to enable voice calls over the internet, while SIP Trunking is a specific implementation or service that facilitates the connection of SIP-enabled devices to the public switched telephone network (PSTN) or IP-based networks for communication purposes. SIP is often used in VoIP systems to establish, modify, and terminate multimedia sessions, but SIP itself is not limited to voice only and can handle various types of media. Let's understand this difference through a comparison table:


Key difference VoIP SIP Trunking
Definition Technology for voice calls over the Internet Protocol/method to connect SIP-enabled devices to the internet or PSTN
Data Transfer Primarily voice data Voice, video, text messages, and fax data
Supported Services A technology for enabling VoIP calls Supports voice, video, instant messaging, and fax
Functionality Enables VoIP calls between IP-enabled devices Facilitates VoIP calls and multimedia data transfer
Scope Part of the SIP Trunking system Part of the VoIP system
Purpose Facilitates voice communication Provides connectivity for VoIP calls and multimedia
Usage Foundation for making VoIP calls Enables VoIP calls and multimedia data transmission
Examples Software-based VoIP apps, IP phones SIP Trunk connecting IP-PBX to the internet/PSTN


Choosing the right communication solution for small businesses and startups: VoIP vs. SIP Trunking

As a small business or startup, you're looking for cost-effective and flexible ways to connect with clients, customers, and team members. The decision between VoIP and SIP Trunking depends on your business's unique needs. For startups prioritising cost-effective, straightforward communication, VoIP might be the way to go. On the other hand, if you seek a unified platform that accommodates growth and multimedia transmission, SIP Trunking could provide the versatility your business requires. Evaluate your priorities, assess your budget, and envision your future needs to select the communication solution that propels your small business or startup toward success.

Making a decision between the two prominent options, VoIP and SIP Trunking can be easily achieved through understanding the following pros and cons of both:

VoIP for small businesses and startups



As a cost-efficient solution, VoIP allows you to make local and international calls at a fraction of the cost of traditional phone systems.


VoIP grows with your business. You can easily add or remove lines without the hassle of new hardware installations.


VoIP offers an array of features, from call forwarding and voicemail transcription to video conferencing, enhancing your communication capabilities.


With VoIP, you're not tethered to a physical location. Stay connected on the go through mobile devices, ensuring you never miss an important call.


Dependent on Internet: VoIP quality relies on a stable internet connection. Any disruption can affect call quality.

SIP Trunking for small businesses and startups



SIP Trunking eliminates the need for multiple physical lines, minimising expenses while maximising connectivity.


Use various devices – from laptops to smartphones – to make and receive calls under the same number or extension.

Disaster Recovery

SIP Trunking's failover options ensure that your communication remains intact even during network outages.

Multimedia Support

Transmit not only voice but also videos, texts, and even faxes, creating a comprehensive communication platform.


Initial Setup: Implementing SIP Trunking may involve a more complex setup compared to basic VoIP solutions.

Final Words

In conclusion, VoIP and SIP Trunking are two essential technologies that have revolutionised modern communication, enabling businesses to make voice calls and transfer multimedia data over the internet. While both technologies share the common goal of enhancing communication efficiency, they serve distinct purposes in the digital landscape.

VoIP, or Voice over Internet Protocol, is the underlying technology that allows voice calls to be transmitted as digital data packets over IP networks. It offers numerous advantages, including cost savings, improved call quality, and a wide range of advanced features that traditional phone systems lack.

On the other hand, SIP Trunking, or Session Initiation Protocol, is a specific implementation that connects SIP-enabled devices, such as IP-PBX systems, to the internet or the PSTN. It goes beyond voice and supports the transfer of multimedia data, making it a versatile solution for businesses seeking comprehensive unified communication services.

In making a decision between VoIP and SIP Trunking, businesses must consider their specific needs, budget constraints, and long-term communication objectives. By understanding the differences between these technologies, organisations can make informed choices to upgrade their phone systems and embrace the benefits of modern communication solutions.

For small businesses and startups, communication is highly important. VoIP offers cost-efficiency, scalability, and mobility, while SIP Trunking brings cost savings, flexibility, and multimedia support. Consider factors like internet reliance and setup complexity to find the best fit for your business growth and connectivity needs.

Wavetel Business is a leading telecom service provider offering cutting-edge solutions for businesses. With a focus on reliability and innovation, they empower organisations with seamless communication services to stay connected and thrive in the digital world.

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