On the 27th November 2018 Nexmo will be adding a new subnet 18.104.22.168/28 to the range we use to send callbacks via HTTP requests from our US data centre. These callbacks may include SMS delivery receipts, inbound SMS, Voice API callbacks, NCCO download requests, audio file download requests. If you are whitelisting traffic from Nexmo then you will need to make the necessary updates on your side to avoid any disruption to your traffic.
On December 17th, 2018 we will be deprecating the following subnets - 22.214.171.124/28, 126.96.36.199/28 and 188.8.131.52/29. Any time after this date you may wish to remove these subnets from your firewall configuration. We will no longer use these IPs to send traffic to our customers.
More information can always be found on this in our Knowledge base article What IP addresses should I whitelist (https://help.nexmo.com/hc/en-us/articles/204015053-What-IP-addresses-should-I-whitelist-in-order-to-receive-HTTP-requests-from-Nexmo
-) in order to receive HTTP requests from Nexmo - please subscribe to follow this article to ensure you receive updates for the latest information on our IP ranges.
We apologise in advance for any inconvenience this may cause. If you have any questions about this please don’t hesitate to contact your account manager or submit a support request at https://help.nexmo.com