Discovering an embedded subscriber identification module root discovery service endpoint

A system comprising:

• data processing hardware;
• and
• memory hardware in communication with the data processing hardware, the memory hardware storing instructions that when executed on the data processing hardware cause the data processing hardware to perform operations comprising:
• receiving a request to provision an embedded subscriber identity module (eSIM) profile to an eSIM-enabled device, the request including a proxy eSIM identifier (EID) prefix and the eSIM profile associated with a service provider of a mobile communication service a user of the eSIM-enabled device subscribes to;
• determining whether the proxy EID prefix includes an address of a target discovery server the eSIM-enabled device is configured to connect to;
• when the proxy EID prefix includes an address of the target discovery server, extracting the address of the target discovery server from the proxy EID prefix;
• and
• using the address of the target discovery server extracted from the proxy EID prefix, registering a discovery event with the target discovery server, the discovery event indicating that the service provider has reserved the eSIM profile to the proxy EID or an actual EID assigned to the eSIM-enabled device.