Each business phone system (aka PBX), installed on premise or in the cloud, needs to be configured with a number of user extensions (for the employees) and a number of outside lines (to make or receive calls from outside of your business phone system). See diagram below.
When a user extension needs to place a call to the outside world, the PBX seizes one of the available outside lines. For most businesses, the ratio of User Extensions to Outside Lines is about 3:1. This can vary depending on usage (for instance in call centers).
For the Cloud PBXact service, we accomplish the task of configuring your hosted system with Trunk+User licenses and User Only license definitions.
Some terminology:
Business phone system are often referred to as PBX (Private Branch Exchange)
User Extensions are often referred to as Seats
Outside lines are often referred to as external call paths, trunk lines or trunk channels
For the Cloud PBXact service, we use the terms Trunk+User and User Only. These are two different types of licenses. The Trunk+User license provides both a User Extension and an Outside Line (also called "trunk") for your system. Each User Only license provides a User Extension for your system. The diagram below shows a system with 2 Trunk+User licenses and 3 User Only licenses, for a total of 5 seats and 2 Trunk Channels.
When a user running on either a Trunk+User or a User Only license needs to place a call to the outside, the Cloud PBXact PBX will select an available outside line. There is no difference of end user features between a Trunk+User and User Only licenses, they all have access to the same functionality. A User Only can make calls to outside line - it is not limited to make internal calls.
Most businesses operate on a 3:1 ratio of User Extensions to Outside Lines. For more complex cases - such as call centers, please contact us.
Case 1: 20 users office
Number of User Extensions: 20
Number of Outside lines: 20 / 3 = 7 (rounded up)
Number of Trunk+User licenses: 7 (same as number of Outside lines)
Number of User Only licenses: 20 - 7 = 13
So in this case you would order 7 Trunk+User and 13 User Only licenses for your Cloud PBXact system.
Case 2: 10 users office
Number of Extensions: 10
Number of Outside lines: 10 / 3 = 4 (rounded up)
Number of Trunk+User licenses: 4 (same as number of Outside lines)
Number of User Only licenses: 10 - 4 = 6
So in this case you would order 4 Trunk+User and 6 User Only licenses for your Cloud PBXact system