Microsoft releasing a new set of IP address ranges for Teams Direct Routing

If you are using Direct Routing for your organization's PSTN calls to Microsoft Teams and you have a specific IP range allowed on your ACL rules in Firewall, you need to review your firewall rules and include the new IP ranges for signaling.

Microsoft Teams Direct Routing Global connection points FQDNs:

Configure these SIP FQDNs in the right order/priority with the same weightage.

sip.pstnhub.microsoft.com –  This is the Global FQDN and you must be configured on your SBC proxy set first. When the SBC sends a request to resolve this name, the Microsoft Azure DNS servers return an IP address pointing to the primary Azure data center assigned to the SBC. The assignment is based on the performance metrics of the data centers and geographical proximity to the SBC. The IP address returned corresponds to the primary FQDN.

sip2.pstnhub.microsoft.com – If the Primary FQDN is unavailable then the SBC will send the SIP request to Secondary FQDN and this is geographically mapped to the second priority region.

sip3.pstnhub.microsoft.com – If Primary & Secondary is not available then the SBC will send the SIP request to Tertiary FQDN before the call got disconnected and this is geographically mapped to the third priority region.

If you have configured a specific IP range in your internet egress firewall then you need to update your rules to continue the service.

Existing IP ranges allowed on the firewall: -

52.114.16.74/32
52.114.20.29/32
52.114.14.70/32
52.114.7.24/32
52.114.76.76/32
52.114.75.24/32
52.114.132.46/32
52.114.148.0/32

SBC connections to Microsoft Teams: -

New IP ranges: -

To ensure that this change doesn’t affect your service availability make sure that your Session Border Controller and Firewall are configured to use the below-recommended IP ranges.

52.112.0.0/14
52.120.0.0/14