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One of the banes of the Internet is identity theft. Therefore, if you accessed 2 million websites, your identity is littered on those sites. Meanwhile, the Internet seems unavoidable, as the majority of people need it. Simply put, digital identities are scattered online and are subject to being compromised. Consequently, hackers and other cybercriminals use them for economic gains, as well as identity theft.

The safety, privacy, and transparency of data becomes difficult because many people rely on unverified data, instead of verifiable data. While the Internet is not transparent, secure or has a single point of failure, Blockchain comes to the rescue. When thinking about this, a novel identity model called Self-Sovereign Identity, comes to mind. This article explicitly discusses self-sovereign identity on Blockchain with a few considerations.

Before discussing Self-Sovereign Identity, let’s first define digital identity. According to Scott Fulton III, a moderator at the Computer Shopper Information Exchange (C*SIX), digital identity consists of the credentials necessary to access resources in a network or online, in your name. The credentials include passwords, titles, etc. Since digital identities are often compromised, verifiable identity became an alternative.

Self-Sovereign Identity is a self-regulated, decentralized identity. It is a new digital identity movement where individuals have a means of generating, controlling, storing, and sharing identity. Contrary to the traditional methods of digital identity, individuals assign permission to others who wish to access their identities.

It is often referred to as SSI: the decentralized identity movement. Unlike the centralized counterpart where users need a third party, the user is the center of the framework, as there is no external party controlling it. It is usually in the form of decentralized identity, data from a social media account, a history of transactions on an e-commerce site, or attestation from friends or colleagues. Consequently, the Centralized Identity Model depends on the Internet, while Self-Sovereign Identity is built on distributed technologies like Blockchain. However, it is not fallacious to say that Blockchain is the new Internet. According to Allen, Principal Architect at Blockstream and Co-author of TLS Security Standard, there are ten SSI principles, as highlighted in the Life with Alacrity blog.   

Self-Sovereign Identity on Blockchain

Now that you know the significant problems of digital identity are non-verifiable, single points of failures, let’s focus on how Blockchain can fill the gap. Blockchain is designed as a distributed ledger where nodes operate across the globe. Individuals can own identities remotely when they host or connect to a Blockchain network. Like the Internet issues URLs and other identities, you can create and control a decentralized identity.  

However, contrary to the public opinion that personal identifier information and verifiable identities can be stored in Blockchain, Blockchain is simply a trust-less distributed ledger with security and transparency functionalities. Therefore, Blockchain serves to remotely and securely own and share identities. Blockchain allows individuals, issuers, and credential verifiers to create, assign, and verify credentials. Consequently, the identities are cryptographically secured, immutable, and transparent on Blockchain. Three examples of identity enabled Blockchain are Hyperledger, Corda, and Ethereum. 

Considerations for Implementing Self-Sovereign Identity

There are several projects leveraging Blockchain for identity, including Uport, Civic, UN Building Blocks, among others. Nonetheless, there are questions about types of Blockchain and its requirements. Therefore, let’s look at the various Blockchain types and how they can enhance Self-Sovereign Identity on Blockchain. 

Public and Private 

Although Consortium Blockchain types exist, Blockchain is generally classified as private or public or open and closed networks. The varieties, as stated above, are a function of how accessible they are to the public. When a Blockchain is open to everyone it is public, whereas, a private Blockchain is limited to certain parties. You can find more details about the varieties of Blockchain here. 

For a Self-Sovereign Identity, there are considerations about what goes to the public and who can verify identity on the network. Consequently, the various categories are desirable based on the use case. 

Distributed Ledger Type

In a Self-Sovereign Identity on Blockchain, it is best to consider if a verifier and other identity users need permission to access the credentials. In this case, you chose either a permission or permission-less DLT to suit your design. Hence, the Blockchain identity system can be public permission, public permission-less, or other combinations that meet the requirements of the network. For instance, Hyperledger Indy operates a public permission Blockchain type, assuming there is no private data on the Internet. Hence, it limits access to steward. On the contrary, Ethereum Blockchain operates a private permission Self-Sovereign Identity. 

Consensus

These refer to decision and governance on the network, which helps to secure, incentivize, and enable democratic identity management on Blockchain. 

Sovrin Foundation provides the governing framework on Indy through stewards with a Redundant Byzantine Fault Tolerance. On the other hand, Ethereum chooses its governance using a Proof of Work Consensus and plans on moving to Casper Proof of Stake. 

Final Words

Leveraging on the ingenious functionalities of Blockchain can solve identity theft and other identity issues on the Internet. However, Self-Sovereign Identity on Blockchain considers the kind of DLT, Blockchain and Consensus requirement in the desired use case.