Calls Per Second
Calls Per Second (CPS) is a common industry term which we use to refer to the number of outbound services which Aculab Cloud will start in every second.
For new accounts, Aculab Cloud will start a maximum of one outbound service every second. We impose this limit to play our part in the fight against call spam. We’re happy to increase it, but first we need to know what you’ll be using Aculab Cloud for. So, if you’d like to request an increase, please contact support and we’ll arrange a call to discuss it.
Values to control CPS
When you issue service_start requests, they are queued up and started at a rate consistent with the CPS values you set.
We have two values you can use to control CPS:
Minimum guaranteed CPS
We guarantee to start at least this many of your outbound services every second, measured over a two minute running average. We can only meet this guarantee while you’ve queued up sufficient service_start requests for us to start.
Maximum allowed CPS
We will start at most this many of your outbound services every second.
Where to set the CPS values
Each of those CPS values may be set on your account and, optionally, on your outbound services.
The minimum guaranteed and maximum allowed CPS values for your account are set by Aculab. If you’d like us to change them, please contact support. You can view them on your account’s Settings page.
We charge a monthly fee for minimum guaranteed CPS, because we need to reserve appropriate cloud and carrier capacity for you to use on demand whenever you need it. We do not charge for maximum allowed CPS, because we do not need to reserve capacity. Instead, we rely on the excess capacity we maintain in order to be able to start outbound services quickly enough for less time critical use cases.
Outbound service CPS
The minimum guaranteed and maximum allowed CPS values for each of your outbound services are set by you. You can set and view them on your outbound services page, and also on the General tab when editing an outbound service.
How can I use them?
Let’s take the example of a system which calls patients to remind them of medical appointments. It will call each patient a week, a few days before, and then on the day a few hours before their appointment. The calls are all placed from outbound services, and each type of call has different time constraints.
The timing of the calls placed in the days before the appointment is not that critical – any time between 9am and 5pm will do. So, they may be placed by an outbound service with high maximum allowed CPS and zero minimum guaranteed CPS. These services run within our excess capacity, generally achieving rates well in excess of the industry norm default 1 CPS. No capacity needs to be reserved so we do not charge a monthly fee.
However, the timing of the on-the-day calls is more critical – each must be placed around three hours before the appointment. To guarantee that the calls keep up with the appointments and to allow them to be placed at the right time, they must be placed by an outbound service with minimum guaranteed CPS set to the appointment rate (per second), summed across all the practices the user is serving. These services run within reserved capacity, for which we charge a monthly fee.
Why is this useful? The minimum guaranteed CPS, which attracts a monthly fee, is required only for the on-the-day calls – only one third of the total. You don’t need to pay a monthly fee for the earlier calls, because their more relaxed timing allows us to place them within our excess capacity. By keeping in contact with our customers to understand their usage patterns, we ensure we keep sufficient excess capacity available to place calls within these long time windows.