The core of this use-case is to link a couple of cloud datacenters. Instead of using directly the link to encrypt all the traffic, as has been done in other use cases, here the QKD systems will be integrated in the cloud infrastructure to provide secret keys as a service. In this way, client applications can request keys to encrypt only the data that needs it, thus optimizing the infrastructure and making QKD available to all users of the cloud. Since many business, including banks, are migrating all their IT services to cloud providers, this is a significant application. As a starting point an implementation using two OpenStack deployments in two nodes of the network will be used, extending it later to more places to study the scalability and performance of the network. The number of requests per time unit will be optimized while providing scalable solutions.