Digital identities play a vital role in an increasingly digital world. These identities often rely on central authorities to issue and manage them. Central authorities have the drawback of being a central trusted party, representing a bottleneck and single point of failure with exclusive control of identity-related data. Self-sovereign identity (SSI) tackles those problems by utilizing distributed ledger technology and making users the sovereign owners of their identity data. Nevertheless, SSI, as recent technology, still lacks qualified identity data. This is especially a problem since sensitive services like eGovernment or banking services require identity data issued by a qualified identity provider; thus, SSI - based identities cannot be used for these services. In this paper, we propose a concept for deriving identity data from an existing identity system into an SSI in a fully privacy-preserving way by additionally supporting offline verification. This way, we enable a chain of trust from the existing identity system to the SSI system by introducing a novel trust model. Our concept utilizes novel cryptographic primitives to support efficient and privacy-preserving identity showing as well as revo-cation. To underline the feasibility of our concept, we implement a proof system and benchmark the related use cases.

We present a framework that allows monitoring of the cloud-based applications and environments to verify fulfilment of Service Level Agreements (SLAs), to analyse and remediate detectable security breaches that compromise the validity of SLAs related to storage services. In particular, we describe a system to facilitate identification of the root cause of each violation of integrity, write-serializability and read-freshness properties. Such a system enables executing remediation actions specifically planned for detectable security incidents. The system is activated in an automated way on top of storage services, according to an SLA, which can be negotiated with customers.