  Advances in emerging technologies have accelerated digital transformation
with the pervasive digitalization of the economy and society, driving
innovations such as smart cities, industry 4.0 and FinTech. Unlike
digitization, digitalization is a transformation to improve processes by
leveraging digital technologies and digitized data. The cyberspace has evolved
from a hardware internetworking infrastructure to the notion of a virtual
environment, transforming how people, business and government interact and
operate. Through this transformation, lots of personal data are captured which
individuals have no ownership or control over, threatening their privacy. It is
therefore necessary for the data owners to have control over the ownership,
custody and utilization of their data and to protect one's digital assets and
identity through proper data governance, cybersecurity control and privacy
protection. This results in the notions of data sovereignty and digital
sovereignty - two conceptually related terms, but different focuses. This paper
first explains these two concepts in terms of their guiding principles, laws
and regulations requirements, and analyse and discuss the technical challenges
of implementing these requirements. Next, to understand the emerging trend
shift in digital sovereignty towards individuals to take complete control of
the security and privacy of their own digital assets, this paper conducts a
systematic study and analysis of Self-Sovereign Identity, and discuss existing
solutions and point out that an efficient key management system, scalability
and interoperability of the solutions and well established standards are some
of its challenges and open problems to wide deployments.
