Skip to main content
Access Control List

Enhance your security with Telnyx's Access Control List. Dive into IP whitelisting, dynamic IPs, and CIDR block management.

David avatar
Written by David
Updated over a week ago

Access Control List

The Access Control List section is a preemptive measure we have applied to help make sure your IP does not get blocked by our DDoS mitigation service. We are adding all IP addresses here to an allow list in order to prevent this.

We need all your IP addresses that interact with any of our services. This is not just for voice, this is also for messaging, call control and API in general.

What happens if I'm using a dynamic IP?

We have been adding IP addresses from credential registrations, IP authentication, and IP addresses from previously connected calls. If your dynamic IP has been able to register and make calls with us, we should have added it already.

If you are adding IPs from my connections, does that mean I do not have to add my IPs anymore?

We prefer to err on the side of caution. Please take the time to add your IP addresses to the Access Control List list on your portal account.

I have a CIDR block and the portal won't let me add the IP addresses, what can I do?

We currently allow /24 as the largest subnet that can be added for for CIDR Blocks. If you need a larger subnet, please contact our support team and they'll help you add that CIDR block.

How long after adding my IP to the Allowed lP list will it take for my traffic to be allowed through?

This process has been automated and all IP addresses are being actively synced between our Access Control List and our DDoS mitigation service. The sync should be running every minute.

The resource has been locked?

"The resource has been locked.". As a precaution, the adding of IP addresses is not available for new accounts. Please request level 2 verification and once approved you will be able to access this resource.

Why is my IP still in a pending state in the access control list?

The front-end may show the IP in a pending state, it can take up to one hour before turning active.


  • For security purposes, only the owner of an organisation will be able to add IP addresses to the portal.

  • The IPs we add from internal systems are meant to aid customers in the event of a DDoS attack so their traffic won't get blocked. The fact that an IP doesn't show up in the list does NOT mean that traffic from that IP will be blocked under normal circumstances.

  • If you still have issues after adding your IP addresses, please contact our support team.

  • In addition, if an IP was on the list and was subsequently removed this is because we no longer detected receiving any traffic from that IP within a 7 day period. Once you start sending traffic again from that IP address, the IP will show in the ACL list.

Did this answer your question?