The Best SIP Calling Guide You’ll Receive: What, Why & How

We’re almost in 2025. Let’s talk about where your business investments are heading: probably the best product or service, hiring skilled employees, the best UI, and more. 

But how about your customer interaction?! Investing more in your brand’s infrastructure won’t grow as you want if your customer doesn’t have smooth access to interact with you.

Well, don’t think beyond good voice call communication whenever your customer tries to reach you. This is where SIP calling comes in. 

Session Initiation Protocol (SIP) acts as a virtual phone line that works with Voice Over Internet Protocol (VoIP) to deliver real-time voice and video call communication via the Internet. 

“A Study from AWS discovered that SIP calling is reliable in 99.9% of all business situations.”

In this article, we will discuss SIP calling, how it works with VoIP, who can choose SIP trunking, and how to set it up in detail.

What is SIP Calling?: Access to Global Communication

Session Initiation Protocol, known as SIP, is a technology that allows you to make and receive phone calls over the Internet instead of using traditional phone lines. These calls are interchanged with VoIP calls. 

Imagine you’re having a video call with your friend using your laptop. You’re using the Internet to connect and establish a connection. Now, imagine you’re using the same internet connection to make regular phone calls; that’s essentially what SIP calling is. 

 

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Traditional Phone Lines Vs. SIP Calls

Private Branch Exchange (PBX) systems or Primary Rate Interface (PRI) lines are connected to the Public Switched Telephone Network (PSTN). 

This is how traditional phone lines are connected. The PSTN is responsible for routing each call to get connected. So, what’s the problem? These traditional phone lines are time-consuming and expensive to establish. 

However, SIP calling, on the other hand, no longer needs a physical connection with multiple phone lines on the ground. It uses the SIP protocol with VoIP to transmit voice, video, and data. 

Feature	Traditional Phone Lines	SIP Calls
Infrastructure	Physical network	Internet
Technology	Analog	Digital
Flexibility	Limited	High
Features	Basic	Wide Range
Cost	Higher	Lower

How Does SIP Calling Work: End-to-End Session Explained

Session Initiation Protocol (SIP) is a sophisticated communication technology that supports simultaneous interactions in various communication sessions.

Here’s a more detailed breakdown of the SIP and VoIP calling process:

❇️ Conversion: The first step in the SIP calling process is conversion, where your phone or computer converts your voice into a digital data packet from analog to digital. 
❇️ Packet Formation & Transmission: These digital data are later encapsulated within SIP signaling, where all the information about the call will be stored, such as the caller’s and recipient’s phone numbers, the type of call (voice or video) and the quality of the service.
❇️ SIP Server Interaction: Another major component is the SIP server, which manages the call. The SIP agent on your mobile or computer sends the SIP signaling packets to the SIP server, which acts as a central hub and routes them to the desired destination.
❇️ Routing: The SIP server utilizes its routing algorithm to find the best path for the call based on network congestion, call quality and cost. Later, it sends the SIP signaling packets to the recipient’s SIP server.
❇️ Session Establishment: The recipient’s SIP server receives the SIP signaling packet from the sender and determines if the receiver is available to attend to the call. If the recipient is available, the SIP server establishes a session. 

Benefits of SIP Calling: Top 5 Pros for Business Communication

The benefits of SIP calling include cost-effective communication channels, high scalability, unified communication solutions, high-quality calls, and excellent customer experience. Let’s look into detail.

➡️ Cost-Effective Communication Channels

The first thing I would like to remind you is to “Think about your business phone bill.” Either way, expanding your business landline will involve a large installation fee. 

Now, imagine you’ll cut this down to almost half of the cost in a one-time investment. SIP calling saves your monthly bill from the landline providers. In SIP calling the internet connection will determine the overall call quality. 

You can also save your investment from expensive software, high-tech installation, maintenance costs, and no potential service disruptions.

➡️ Scalable as You & Your Business Want

You may think the cost is low compared to traditional phone lines. But if my company grows, will I end up paying much more? 

Well, the answer is no. Scaling SIP calling is a piece of cake. You don’t need to invest in any high-end infrastructure or additional phone lines. With SIP calling, scalability and growth are always welcome abroad. 

Using SIP trunking entirely relies on the internet. Everything from voice calls to real-time video conferencing can be handled on the cloud, so you don’t end up buying physical lines.

➡️ Unified Communication Solution

Once again, the comparison with traditional phone lines shows that even though the connection requires hardware and infrastructure, you won’t have a conversation apart from voice.

According to BlueWire, an average employee can save 115 minutes per day with streamlined, unified communication. 

SIP call online combines the virtual communication space that supports voice, video, and whole contact center solutions for enterprise infrastructure. 

This saves time and productivity by eliminating juggling between different communication platforms.

➡️ Easy Integration with External Apps & Tools

SIP calling is more flexible and scalable than traditional lines. This means you can integrate this with any app or website, and this can be used on any device like mobile or desktop. SIP cloud calling includes a lot of real-time collaboration tools including multimedia sharing at your fingertips. 

Apart from client-business communication, SIP and VoIP support internal collaboration, making it easy to work.

➡️ Easy to learn, use & integrate 

Whether it’s about building traditional phone lines or building a chat app, starting from scratch requires time, cost, and resources to complete. 

However, cloud based communication channels don’t give any leap about complex requisites. It can be easy to integrate via chat APIs with minimal developer support. Enterprises can get a dedicated API and SDK documentation as additional resources. 

With self-hosted SIP calling solutions, you can even customize the features and look of the app as you need.

SIP Vs. VoIP: Is Both the Same?

Generally, SIP and VoIP are different. These are not rival technologies for users to choose between. SIP is the umbrella term for making and receiving calls over the Internet, whereas VoIP establishes a connection between two or more parties by sending packets of data. 

In a nutshell, SIP is the board of hubs to achieve VoIP (voice over Internet protocol). 

SIP protocol works collaboratively with VoIP to maintain the connection between the connected devices. This established connection makes Internet calling easy, fast, and affordable. 

➡️ Is SIP Calling Right for You?: Who can Choose SIP

Simply, you can choose SIP calling if you want to enhance your communication capabilities. SIP for mobile and desktop is an excellent choice for businesses and individuals because of its flexible and affordable nature. 

To pick to the precise right choice, then you can choose:

Suppose you’re an enterprise using existing on-premise PBX systems. Switching to SIP trunking enables various opportunities for seamless communication. Moreover, based on your SIP provider you can choose flexible hosting of on-premise deployment on your own server. 

Apart from enterprises, users across call centers, remote workers, freelance workers, and international travelers can benefit from SIP calling integration.

➡️ Features of Online SIP Calling: Real-Time Collaboration

The features of SIP calls include audio and video calling, call transfer and forwarding, call recording and conferencing. Let’s look into each more elaborately.

❇️ One-on-One Audio & Video Calling: As the main purpose of the SIP trunking, it lets users connect in real-time via one-on-one audio and video calling. 
❇️ Call Transfer and Forwarding: Followed by generic calling, SIP calling allows you to transfer and forward the call to the desired person.
❇️ Call Recording: If you’re running a contact center and handle hundreds of calls in a day, you can record each call for your reference and improvement.
❇️ Conferencing: Whether it’s audio or video call, you can add unlimited numbers of members for an active conference call.

Make Your Company Speak Through SIP Calling

Get your company ready for SIP and VoIP calls! As SIP calling reduces 70% of communication costs compared to traditional phone systems, now it’s your time. 

If you use PBX connections, you can transform your whole phone call experience using SIP trunking. With minimal effort, you can implement a session initiation protocol with multiple features.

Moreover, if you want to establish SIP in a matter of hours, consider self-hosted SIP/VoIP API as the best choice. With MirrorFly, you can customize features and even change the logo, font color and custom font as you want. 

Contact MirrorFly for more information and pricing. Good luck on your SIP connections!

Related Articles:

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