On the 30th January 2019 Nexmo will be deprecating the range of IP addresses and hostnames currently used for Washington DC SIP endpoints:
Hostnames - sip-us1.nexmo.com, sip-us2.nexmo.com
IP Addresses - 220.127.116.11, 18.104.22.168
We recommend that you connect via hostname, sip.nexmo.com, which is already and will remain available. After 30th January 2019 the above hostnames and IP addresses will no longer be available.
Please note that our Dallas SIP endpoints are not impacted by this deprecation.If you are whitelisting traffic in your firewall based on IP then you will need to ensure you have the Dallas IP addresses (22.214.171.124, 126.96.36.199) included as soon as possible. You would therefore need to update these IP addresses by January 30th to avoid any disruption to your traffic.
We apologize in advance for any inconvenience this may cause. If you have any questions please don't hesitate to reply to this email or submit a support request at https://help.nexmo.com