Understanding the Basics of SIP Trunks
In previous discussions regarding SIP trunk setup and the associated monthly charges, we explored the various factors influencing the cost of SIP trunking and how these compare to traditional phone lines. Today, we will delve into the critical question: How many SIP trunks does your business actually need?
What is a SIP Trunk?
A SIP trunk, often referred to as a "call path," essentially allows for one phone call to be made to the outside world. Therefore, the number of SIP trunks required by your office directly correlates with the volume of calls made. The more calls you need to handle simultaneously, the more SIP trunks you will need.
Key Factors in Determining SIP Trunk Requirements
Assessing Current Call Path Sufficiency
One of the first steps in determining your SIP trunk requirements is to evaluate whether your current number of call paths is sufficient. Have you received complaints from customers or employees about busy signals or difficulties in obtaining an available line for outgoing calls? If so, it may be time to review the number of call paths you currently have. In traditional telephone setups, these are often referred to as PRI circuits.
Utilizing Usage Reports
While some traditional service providers may offer usage reports, these are not always reliable due to their non-digital origins. Such reports may only offer a snapshot of usage rather than comprehensive historical data. However, they can still provide valuable insights into your call patterns and help in planning your SIP trunk needs.
SIP Trunk Ratios for Different Company Sizes
The 3:1 Rule for Larger Companies
For businesses with 100 employees or more, a common rule of thumb is to maintain a 3:1 ratio of phones to call paths. Why does this ratio work?
- Companies of this size typically have a mix of heavy, medium, and light phone users.
- On average, even heavy users are on calls for no more than three hours per day.
- Not all employees are present in the office simultaneously.
As a result, it's rare for every employee to be on the phone at the same time, allowing for a higher phone-to-trunk line ratio. For those interested in more complex calculations, exploring Erlang Telecom Load Calculations can provide more detailed insights.
Adjusting Ratios for Smaller Companies
For smaller offices with fewer than 50 employees, the 3:1 rule becomes less applicable. The smaller the office, the greater the likelihood that everyone will need to use the phone concurrently. In some cases, very small offices may require more SIP trunks than they have phones.
#### Recommended SIP Trunks Based on Phone Count
| Number of Phones | SIP Trunks Needed |
|------------------|-------------------|
| 2 | 4 |
| 5 | 6 |
| 10 | 6 |
| 25 | 12 |
| 50 | 23 |
| 100 | 30 |
Tailoring SIP Trunk Needs to Your Business
This guide serves as a general framework to help you determine your SIP trunk requirements. However, every business has its unique needs and call patterns. If the thought of calculating your call capacity seems daunting, our team of experts is here to assist. Feel free to contact us via phone or email, and our technicians will be more than happy to provide tailored advice to meet your specific telecommunications needs.
