A SIP Trunking connection creates a virtual connection between the traditional public switched telephone network (PSTN) and cloud-based VoIP communication.

SIP Trunking allows premise-based business phone systems to take advantage of the advanced features and benefits of VoIP.

The Plain Old Telephone Service (POTS) relies on copper wiring for making and receiving telephone calls. However, using SIP Trunking, data is digitally transmitted over IP networks and virtually connected to the PSTN. Essentially, a SIP Trunk is the virtual equivalent of one traditional phone line – but the service goes far beyond VoIP voice calls.

A SIP Trunking system replaces landlines with advanced cloud-based VoIP communications, allowing IP PBX systems to operate without landlines. IP PBXs are any PBX system that supports SIP.

A PBX system is an internal business phone network that allows businesses to run their own private, company-wide phone system. By doing this, a business will avoid paying a premium for additional phone lines.

By using SIP Trunking, businesses can connect their existing premise-based phone systems and compatible hardware to the Internet instead of copper wires to communicate over the Internet.

Both SIP and VoIP are Internet-based voice communication protocols, but they’re not the same. VoIP stands for “Voice Over Internet Protocol”, meaning that it relates only to voice calls over the Internet.

Although VoIP calls are a part of SIP, SIP is not limited to voice calls. SIP users have the option of communicating via voice, SMS texting, video communication, and instant messaging with file sharing, as discussed earlier in this post.

Cost savings are the most well-known benefit of SIP Trunking, especially when compared with standard phone systems. There are numerous ways to reduce business communication costs using SIP Trunks, ranging from 50 to 70 percent. A SIP trunk is also more than 25% cheaper than a PRI trunk (Primary Rate Interface). 

As a result, you won’t have to worry about costly hardware and equipment like servers, hard phones, and monthly maintenance fees. Moreover, SIP is capable of handling 20+ simultaneous calls per trunk, so you won’t have to pay for additional lines or setup fees.

Negative aspects:

There may be incompatibilities between existing phone systems and SIP Trunking, which may force you to upgrade your equipment for a higher upfront cost than you expect. Furthermore, some providers require long-term commitments for bundled plans or charge hefty service fees. Make sure you get a breakdown of pricing from providers.

SIP Trunking provides the mobility and flexibility needed by today’s increasingly remote and blended workforce. As VoIP communication is conducted over the Internet, agents aren’t restricted to specific locations (and hence aren’t tied to their desks).

The company’s phone system can be accessed from anywhere, and on any device, that has Internet access. Calls can be sent/received on desk phones, desktops, laptops, tablets, and smartphones. The ability to forward calls to multiple numbers without disconnecting the call adds even more mobility.

Negative aspects: 

Any time business communications or sensitive data leave a physical office, there’s a greater risk of security breaches.

In particular, unsecured or public Wi-Fi networks may make it difficult for users to access their communication tools. Be sure your SIP provider offers end-to-end encryption, has third-party security standards certifications and conducts regular vulnerability testing.

A traditional phone system offers only basic calling features, such as voicemail, call waiting, call blocking, and caller identification. For new businesses or solopreneurs, these features may suffice, but for today’s business communications, more is needed.

• ACD (Automatic Call Distribution) and IVR (Interactive Voice Response)
• Routing and Forwarding of Calls
• Call Monitoring, Call Recording, and Call Transcription
• Voicemail-to-Email and Visual Voicemail
• File Sharing and Instant Team Chat
• Reporting and Analytics for calls
• Third-Party Software Integrations 
• Call Park, Call Transfer, Call Flip, Hot Desking
• Queueing for Calls

Negative aspects:

It can be challenging to learn how to use advanced VoIP features and additional communication channels.

Team members used to traditional phone systems may have some difficulty adjusting to managing phone calls on desktop computers or mobile devices. Analyzing detailed analytics, learning new terminology, and planning call paths can be challenging. Because of this, it’s important to evaluate the customer support, onboarding, and training offered by a SIP Trunk provider.

Setup of a SIP Trunking System requires:

• Static port mappings and port address translations are supported by a router and firewall
• A Fully Qualified Domain Name (FQDN) that resolves to a static external IP address
• A sufficient bandwidth (27-120 kbps per call)

After setting up the basics, you can begin the installation.

 Step 1: Pick a provider

The first step in setting up a SIP trunk is to select a business VoIP service provider that is SIP-compatible.

Step 2: Test the firewall

Make sure the firewall is compatible with the SIP port and the audio port range. Troubleshoot the firewall if necessary.

Step 3: Connect your VoIP account

Next, configure your VoIP account. In your user interface, you should see an option for adding SIP trunk settings. Based on your geographic location and the numbers assigned to your new trunk, choose the appropriate options.

Step Four: Create SIP call routing rules for outbound calls

Provide a route for these outbound calls. You will find your SIP trunk and each new gateway in the route dialogue box. Alternative outbound rules may also be available if the first set of routes is unavailable. Transform the number matched with the outbound rule by stripping the digits and using the prepend option.