In a web browser, enter the following URL while placing the public IP address of your Expressway or endpoint at the end of this URL. 
https://ds.ciscospark.com/v1/region/ 
For Example: https://ds.ciscospark.com/v1/region/72.163.4.161

You can see in the response that the country code for this address is “US”. This country will be considered the source country for media originating at the 72.163.4.161 address. So it is important to verify that your public addresses map correctly to ensure that we will route you to an expected Webex Media Node location. 
If the country returned is not what you expect, you will need to submit a request to have the location corrected for your IP addresses with our GeoIP location provider Maxmind. Here is the direct URL for submitting a Data Correction request: https://www.maxmind.com/en/geoip-location-correction