What Are Channels and How Many Do I Need?
What Is a Channel?
The number of channels determines how many connections can be active simultaneously.
The number of channels required does not necessarily depend on the number of telephone devices.
A phone number can be used on several devices. Similarly, several phone numbers can be configured on one device.
Two channels are required for each phone number forwarding when an incoming call is received.
Users and Channels
A user is any person or independent location, such as a break room.
A user can use several devices.
For example, if a project manager uses the same phone number on a telephone, a smartphone and a tablet, this still counts as one user.
The number of channels must not be lower than the number of users.
Case Study 1: «Luftig» Company
Initial Situation
A company in the ventilation systems service sector employs 25 people.
20 employees work as service technicians and make calls via the mobile network.
Fixed telephone devices are used by one employee in the secretarial office, two project managers, the warehouse manager and the managing director.
In addition, there is one telephone device in the break room and one in the workshop.
Seven channels are required for this situation.
Additional Integration of Smartphones
With suitable apps, fixed-line numbers can also be used on smartphones.
The apps require an Internet connection via Wi-Fi or the mobile data network.
This allows a project manager, for example, to make calls using the same phone number, regardless of whether they are in the office or at a construction site.
The service technicians can also make calls using the app.
This adds another 20 channels.
Further information can be found in the following article:
https://www.green.ch/en/ipcall-on-iphone-ipad-or-android-devices
Channel Calculation Without a Simultaneity Factor
If all telephone devices and smartphones are taken into account, 27 channels are theoretically required.
To prevent bottlenecks with call forwarding, a factor of 1.5 to 2 is taken into account.
This allows the entire telephone system to be operated with 41 to 54 channels.
Channel Calculation With a Simultaneity Factor
The secretarial office, the managing director, the project managers and the warehouse manager frequently need the telephone. These users are taken into account with a factor of 1.
The telephone devices in the break room and workshop are rarely used. These users are taken into account with a factor of 0.5.
It is assumed that no more than 25 percent of the service technicians make calls at the same time. These users are taken into account with a factor of 0.25.
Call forwarding is also taken into account with a factor of 1.5 to 2.
Taking the simultaneity factor and call forwarding into account, the entire telephone system can be operated with 27 channels.
Case Study 2: «Schönreisen» Company
Initial Situation
A company offering holidays and travel services in Switzerland operates 26 branches and a head office with a total of 80 employees.
Each employee has their own telephone device.
Channel Calculation Without a Simultaneity Factor
If all telephone devices are taken into account, 80 channels are theoretically required.
To prevent bottlenecks with call forwarding, a factor of 1.5 to 2 is taken into account.
This allows the entire telephone system to be operated with 120 to 160 channels.
Channel Calculation With a Simultaneity Factor
It is assumed that up to 85 percent of employees make calls at the same time during the peak season.
Call forwarding is also taken into account with a factor of 1.5 to 2.
This allows the telephone system to be operated with 102 to 136 channels.
Related Articles
Information on setting up and configuring Green Talk can be found in the following article:
https://www.green.ch/en/talk-installation-and-configuration
Information on using Green Talk on smartphones can be found in the following article:
https://www.green.ch/en/ipcall-on-iphone-ipad-or-android-devices