Call Assure FAQ


Christy Belcher


What is Call Assure?

Call Assure is Bandwidth’s disaster recovery solution designed to safeguard your U.S. toll-free traffic from extraordinary disruptions. When the Bandwidth core network is unavailable, this highly reliable cloud platform insulates and safely routes your traffic around it to protect your toll-free calls. 

How does Bandwidth determine if its core network is unavailable and Call Assure needs to be activated?

Bandwidth monitors the network 24/7 using standard methodologies to alert our teams when a problem is detected. These alarms, in conjunction with a carefully designed standard operating procedure, allow our team to determine if toll-free origination services are unavailable.

The Bandwidth core network is considered unavailable when the inbound toll-free service experiences a P1 or P2 outage, meaning that a service-impacting event affects all customers’ inbound toll-free service.

Outage types:

  • Priority 1 (P1) – Inbound toll-free service is unavailable.
  • Priority 2 (P2) – Inbound toll-free service is impaired.

Do I need to do anything if Bandwidth determines that Call Assure needs to be activated?

No action is required on your part. Once we determine that the Bandwidth core network is unavailable, we’ll notify our Network Operations Center (NOC) who will then switch your inbound toll-free traffic to the Call Assure network. Once we’re confident that our core network is once again available, the NOC team will switch your inbound toll-free traffic back.

How will I know if Call Assure has been activated or deactivated?

Bandwidth will send out a notification to all Call Assure customers when Call Assure is activated and again when inbound toll-free traffic is switched back to the Bandwidth's core network. You can subscribe to these notifications on the Bandwidth Status Page by following these instructions.

What do I do if I have an issue with my traffic or a toll-free number?

If you’re experiencing issues, please open a ticket with our Technical Assistance Center (TAC). Most issues are not related to Bandwidth's core network and can be solved without the need to invoke Call Assure.

I used the OPTIONS request to ping the Call Assure SBCs. Why am I getting a 500 response code?

This is an expected behavior. When Call Assure isn’t active, the Session Border Controllers (SBCs) remain in an idle state. Normally, an SBC in an idle state would return a 200 OK when pinged, however, the Call Assure SBCs are set up a bit differently. Since we don't do termination on the Call Assure trunk groups, we also don't load customer IPs into the customer trunk groups. Any SIP OPTIONs sent to a Call Assure SBC will get a 500 response. This shows the SBC has processed the OPTION, but didn’t find a trunk group with your source IP.

Is there a way to test the Call Assure SBCs after completing onboarding?

Yes, we can provision 1-2 of your low-volume toll-free numbers (TFNs) so that traffic is delivered over the Call Assure network 100% of the time. To set up a test TFN during onboarding or at any other time, please open a ticket. 

Since Bandwidth has two Call Assure SBCs, do I need to indicate a preference?

No, you’ll be provisioned to both SBCs. This provides both redundancy and the ability to load balance between the two SBCs.

How do I set up my trunks to receive traffic from the Call Assure SBCs?

Call Assure uses OTT unencrypted traffic. You must configure your firewall to accept inbound SIP and media ports. Signaling will be sent from the Call Assure SBCs using a unique IP address for each SBC (East & West). These confidential IPs will be shared via an encrypted email during onboarding.  

  • Protocol: UDP Port 5060  
  • Signaling: SIP Port 5060 

Media is anchored to our gateway provider. Unless you’re using session-aware SBCs, or your session-aware SBCs have any use cases or call flows that by default tear down the ports, you need to allow media ports from any IP.  

Do I need to configure my settings in the Call Assure SBCs?

No. If you don’t have Advanced Call Routing (ACR) enabled, relevant Bandwidth Dashboard settings will be automatically copied to the Call Assure SBCs when your account is enabled for the service. Any changes or updates made in the Bandwidth Dashboard will be automatically synced to the Call Assure SBCs. 

I have ACR enabled. How does this work with Call Assure?

Advanced Call Routing (ACR) is a suite of enhanced routing tools offered by Bandwidth that began rolling out in Q3 2023. Since the ACR design uses a different set of proxies than Call Assure, we have to configure Call Assure SBCs a bit differently.

Our current solution involves running an API script to push your trunk settings to the Call Assure SBCs. This API script needs to be run during the Call Assure onboarding and again if you update or add IPs to your trunk. 

Bandwidth will make sure your AWS SBC trunks are set up during onboarding. We can also run the API script for you, but you’re welcome to run it yourself if you’re comfortable doing so. 

Once you’ve made the appropriate updates in the Bandwidth Dashboard, simply open a ticket requesting these new IPs to be pushed to the Call Assure SBCs. If you wish to run the API script in the future, please request a copy of it.

Do all of my TFNs have to be built into Call Assure?

All toll-free numbers (TFNs) on an account configured with Call Assure will be provisioned for Call Assure. Every Call Assure account is audited weekly. Any new TFNs that have been added to the account during the previous week (and are not already on Call Assure) will be built into Call Assure.

Why can’t I use any advanced routing features on Call Assure?

Call Assure is designed to be an autonomous backup (not a replacement for our core network) in the case of a catastrophic event that impacts the Bandwidth core network. When Call Assure is active, all features implemented at the core will no longer work. Features that require a terminating carrier, such as Call Forwarding, will also fail during a Call Assure event.

What are my options if I need Call Forwarding active for a TFN?

Since Call Forwarding is not compatible with Call Assure, any TFNs that require Call Forwarding will need to be added to a non-Call Assure account. These TFNs will not be protected by Call Assure.

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