The list of IP addresses of ODME workers that may get assigned by Microsoft can be obtained here:
https://www.microsoft.com/en-us/download/details.aspx?id=56519
Look for "name": "AzureCloud.northeurope" in the downloaded json file for this region.
ODME workers are cloud virtual machines.
The number of active/running workers depend on the current workload of ODME.
The IP addresses are assigned dynamically to our workers by Microsoft.
List of heading for each Region
EU=AzureCloud.northeurope
Australia=AzureCloud.australiaeast
Canada=AzureCloud.canadacentral
UK=AzureCloud.uksouth
US=AzureCloud.westus2