The answer to this question depends on the unique needs and what your business is seeking out of it. Businesses with traditional PBX phone lines are proactively switching to SIP trunking in their venture of improving communication networks by deploying the internet to process business calls. Businesses already using SIP trunk plans are looking for better versions to minimize the latency of calls and provide customers with better QoS; quality of service. Regardless of where your business stands in the above scenario, the increasing number of SIP trunk providers in the market has made choosing the perfect SIP trunk plan a painstaking business process. 

This blog will walk you through what a SIP trunk is and how to optimize the process of narrowing down the options of SIP trunk providers according to your unique business needs. 

What is Session Initiation Protocol (SIP) 

SIP Trunking is a method of transmitting phone calls over the internet using a VoIP (Voice over Internet Protocol) system. It allows businesses to make and receive phone calls using their existing internet connection, rather than a traditional phone line. 

With SIP Trunking, businesses can use their VoIP phone system to make and receive calls, send and receive faxes, and access other communication tools such as voicemail and call forwarding. SIP Trunking can be used with both on-premises and cloud-based VoIP systems. 

One of the main benefits of SIP Trunking is that it can be more cost-effective than traditional phone lines, especially for businesses that make a large number of calls. It also allows businesses to scale up or down their phone capacity as needed, without the need to purchase additional hardware or phone lines. 

In addition to cost savings, SIP Trunking also offers flexibility and scalability, as it can be easily configured to meet the specific needs of a business. It can also be used with a wide range of communication tools and applications, making it a versatile and powerful solution for businesses of all sizes. 

Choosing the perfect SIP Trunk plan 

The following sections of the blog will cover the factors to consider when choosing the SIP Trunk plan that fits perfectly with your business needs. 

Quality of Service | Latency 

This factor should especially be considered by companies that are not satisfied with their current SIP service and are looking for a better SIP trunk Plan. The unsatisfactory response of businesses to SIP trunk plans is normally associated with poor QoS (quality of service) as they face intermittent drops or choppy audio in business calls. This noise occurs when there is a greater packet loss, high jitter, insufficient bandwidth, or an overloaded server. 

The quality of Internet connection is a key element to deal with these troubles since communication across SIP trunks uses organizational internet connectivity. Different providers offer SIP trunk plans with varying latency. For example, RingOffice SIP trunk plans deliver 0% packet loss, jitter of less than 10ms, and latency below 100ms.  

Sequential DID numbers provision 

DID is short for Direct Inward Dialing and it can be extremely useful for businesses to deliver enhanced customer experience across calls. Before choosing the perfect SIP trunk plan, make sure that your service provider facilitates the provision of DID in your SIP trunk plan. Let us understand deeper what DID is and its significance in business communications.  

What is Direct Inward Dialing (DID) 

DID, or Direct Inward Dialing is a feature of SIP Trunking that allows your business to have its own dedicated phone numbers for incoming calls. With DID, you can assign specific phone numbers to individual employees or departments within your organization, rather than using a shared number for all incoming calls. 

For example, if you have a sales department and a customer service department, you could assign a DID number to each department. This allows customers to directly dial the department they need to reach, rather than going through an automated menu or being transferred to the concerned department. 

DID numbers are usually assigned to your business by the SIP Trunk provider. These can be local, national, or international numbers depending on your business needs. Some SIP trunk providers may also offer virtual numbers, which allow you to have a local presence in a specific location even if your business is physically located elsewhere. Overall, DID is a useful feature for businesses that want to have a professional, organized phone system and make it easy for customers to reach the right department or person. 

Failover Provisions 

In order to increase the quality of SIP trunks offered by third-party service providers, they normally connect the SIP trunks to multiple geographically distributed servers and ensure maximized uptime for your business communication systems. Simply put, when a server malfunctions or is down, your communication signals take a different route in real time, and the end users experience no disruption in communications.  

On the offside, if the server hosting your SIP trunks is down, your business communication lines are down. Therefore, businesses need to check with their SIP trunk providers as to what options they have in dealing with failovers. Ideally, there should be at least one point of presence (PoP) in every region where you would prefer the least latency and high quality of communication. 

For example, RingOffice SIP trunks are maintained on geo-redundant data centers and are backed by 24/7 business class monitoring, built-in security safeguards and emergency failover features (such as Failover Auto Attendants and Voicemail-to-Email options) to ensure enhanced reliability. 


Interoperability is directly associated with the cost-effectiveness of a certain SIP trunk plan. Switching your existing PBX phone system to SIP trunks does not necessarily mean upgrading the entire hardware (e.g., headsets) associated with it. Instead, a good service provider should offer SIP trunks that are compatible with your existing PBX systems. In this way, businesses can save up the costs of procuring new phone systems to enable SIP trunks.  

For example, RingOffice SIP Trunks are compatible with all standard SIP-based VoIP phone systems and gateways. Our supported vendors include well-known names such as 3CX, Asterisk, FreePBX, Grandstream, Patton, Switchvox, Cisco, Sangoma, Panasonic, Mitel, Yeastar, Poly, Yealink, Snom and many more. 

The parameters mentioned above are the fundamental elements every business should look for when choosing the perfect SIP trunk plan. There are other factors that vary from business to business and should be taken into consideration as well. These include: 

  • Coverage for long-distance and international calls 
  • Data security provisions TLS/ SRTP 
  • Scalability options 
  • Flexibility and reliability 
  • Cost-effectiveness 
  • Intuitive statistical dashboard for advanced Call records 

Switching is easy! 

RingOffice offers business-grade SIP trunking services with a range of features that can be tailored to meet the specific needs of your business. We also offer a variety of calling plans to choose from, allowing you to find the perfect fit for your business. Contact us now and our solution consultants will tailor a solution that best fits your business SIP trunking needs.