How does bursting work on IVP SIP Trunks?

This article describes how SIP trunk bursting operates and is configured on the Intelligent Voice Platform

Does the Intelligent Voice Platform support SIP Trunk Bursting?

Yes - SIP Trunks delivered via the Intelligent Voice Platform support “Bursting”, which is the ability for Customers to temporarily exceed their limit on a “best effort” basis if capacity is available in the network.

How does it work?

Bursting allows SIP Trunks to temporarily exceed their provisioned channel limit by up to 50% of their purchased capacity where they have a spike in call traffic, but it is not guaranteed that this capacity is available at any given point in time.

IVP calculates the overall SIP Trunk capacity as follows where bursting is enabled:  Total Channels = Purchased Channels + (Burst = Purchased Channels * 0.5)

For Example, A customer who has a 100-channel SIP Trunk with bursting is enabled will be provisioned in the IVP with a limit of 100 channels (we do not overprovision the number of channels) and the bursting option enabled.

This configures the IVP so that their SIP Trunk will allow them to have up to 150 active calls comprising of:

  1. 100 “Purchased” Channels that are available for the customer
  2. 50 “Burst” Channels that can be consumed if the spare network capacity is available at the time of the call(s)

In practice, the customer could burst beyond 100 Calls up to a maximum of 150 calls provided there is network capacity available, meaning:

  1. The 1st to 100th call would be allowed
  2. The 101st – 150th call would be allowed based on spare network capacity at that point in time and flagged as billable burst consumption if we choose to do so or busied if no spare capacity is available
  3. The 151st call and beyond would be busied out / rejected.

Is there a way to see if a Trunk is Bursting and how much?

In the near future, Bursting utilisation will become visible as part of the IVP Live Metrics that shows SIP Trunk Utilization Statistics.

Is it enabled by Default?

Bursting is not enabled by Default on IVP-based SIP Trunks and must be specifically requested on the sales order if it is a requirement.

Does Bursting Cost Anything?

Bursting is charged on a per-channel basis based on the average burst capacity consumed over the course of the billing period.

How to configure it?

Bursting is enabled by toggling the "Bursting" slider on for a particular SIP trunk to on during the initial provisioning process or via a modification in the IVP Portal.