To secure all communications, Named Data Networking (NDN) requires that each entity joining an NDN network go through a bootstrapping process first, to obtain its initial security credentials. Several solutions have been developed to bootstrap IoT devices in localized environments, where the devices being bootstrapped are within the physical reach of their bootstrapper. However, distributed applications need to bootstrap remote users and devices into an NDN-based system over insecure Internet connectivity. In this work, we take Hydra, a federated distributed file storage system made of servers contributed by multiple participating organizations, as a use case to drive the design and development of a remote bootstrapping solution, dubbed Cornerstone. We describe the design of Cornerstone, evaluate its effectiveness, and discuss the lessons learned from this process.