PROMINENT
BLOCKCHAIN APPLICATIONS ARE:
Secure sharing of medical
data
NFT marketplaces
Music royalties tracking
Cross-border payments
Real-time IoT operating
systems
Personal identity security
Anti-money laundering
tracking system
Supply chain and logistics
monitoring
Voting mechanism
Advertising insights
Original content creation
Cryptocurrency exchange
Real estate processing platform
What is Identity Management?
· Also known as “identity
and access management”, or IAM, identity management includes all the
processes and technologies within an organisation that are used to identify,
authenticate and authorize someone to access
services or systems in that said organisation or other associated ones.
· Examples of this would range from customers and/or employees accessing software or hardware inside a
company/enterprise – and the level of access, privileges, and restrictions each
user has while doing so – or, in a governmental setting, the issuing
and verification of birth certificates, national id cards,
passports or driver’s licenses (that allow a user/citizen to not only
prove his identity but also access services from the government and other
organisations).
The problem with current Identity Management Systems
· Identity has a problem. If it is paper-based, such as birth certificates sitting idly in a
basement of a town hall, it’s subject to loss, theft of fraud.
· A digital identity reduces the level of paperwork and increases
the speed of processes within organisations by allowing for a greater
interoperability between departments and other institutions. But if this digital
identity is stored on a centralised server, it becomes a target for
hackers.
·
Since 2017 alone, more than 600 million
personal details – such as addresses or credit card numbers – have been hacked,
leaked or breached from organisations.
Most of the current identity management systems are weak and
outdated.
Identities
need to be portable and verifiable everywhere, any time, and digitization
can enable that. But being digital is not enough.
Identities also need to be private and secure.
Several industries suffer the problems
of current identity management systems:
Cryptography in Identity Management
· Whenever we need to prove something about our identity
– either our name, address or passport number – there
is a process of authentication.
· A verifying entity confirms that the data we are
claiming about ourselves is true or false. This is usually done through the
verification of our identifying documents.
· These identity verification and authentication processes
make privacy concerns arise.
· Should a verifying entity requesting me to prove my
name with my passport have access to the remaining information contained in my
document while they are looking at it to verify that information?
· Does an entity that request a proof of my age need to
know the day and month I was born?
A blockchain
identity management system that uses Zero-Knowledge Proofs
· A Zero-Knowledge Proof is a method of authentication
that, through the use of cryptography,
allows one entity to prove to another entity that they know a certain
information or meet a certain requirement without having to disclose any of
the actual information that supports that proof.
· The entity that verifies the proof has thus “zero knowledge” about the
information supporting the proof but is “convinced” of its validity.
This is especially useful when and where the prover entity does not trust
the verifying entity but still has to
prove to them that he knows a specific information.
· In an identity management with blockchain scenario, this allows a person
to prove that their personal details fulfil certain requirements without
disclosing the actual details.
· For example, one could prove that she is over 21, without showing her
exact date of birth.
A Blockchain based Identity Management Solution
In identity management, a distributed
ledger (a “blockchain”) enables everyone in the network to have the same
source of truth about which credentials are valid and who attested to
the validity of the data inside the credential, without revealing the
actual data.
The 3 actors
in Identity Management with Blockchain:
1.
Owners,
2.
issuers and
3.
verifiers
· When talking about leveraging blockchain technology for identity
management, it is important to note that there are three different actors
in play:
identity
owners,
identity
issuers and
identity
verifiers.
· The identity issuer, a trusted party such as local government,
can issue personal credentials for an identity owner (the
user).
· By issuing a credential, the identity issuer attests to
the validity of the personal data in that credential (e.g.
last name and date of birth).
· The identity owner can store those credentials in their
personal identity wallet and use them later to prove statements
about his or her identity to a third party (the verifier).
· A Credential is a set of multiple identity attributes
and an identity attribute is a piece of information about an identity (a name,
an age, a date of birth).
·
Credentials are issued by second
parties whom attest to the validity of the data inside
the credential. The usefulness and reliability of a credential fully depends on
the reputation / trustworthiness of the issuer.
How Blockchain brings privacy
and security to Identity Management
· Through the infrastructure of a blockchain, the verifying parties do
not need to check the validity of the actual data in the provided
proof but can rather use the blockchain to check the validity of the attestation and attesting
party (such as the government) from which they can determine whether
to validate the proof.
· For example, when an identity owner presents a proof of
their date-of-birth, rather than actually checking the
truth of the date of birth itself, the verifying party will
validate the government’s signature who issued and attested to this credential
to then decide whether he trusts the government’s assessment
about the accuracy of the data.
· Hence, the validation of a proof is based on the verifier’s judgement of
the reliability of the attestor.
· Leveraging blockchain technology, like Tykn’s digital identity management
system does, establishes trust between the parties and
guarantees the authenticity of the data and
attestations, without actually storing any personal data on the
blockchain.
· This is crucial as a distributed ledger is immutable, meaning anything
that is put on the ledger can never be altered nor deleted, and thus no
personal data should ever be put on the ledger.
Blockchain Identity Management Red Flag: Does personal data go on a
Blockchain?
1. Putting personal data on the ledger puts the privacy of the
users in danger (as it will constantly be subject to hacking and data
breaches). It could always be hacked (if not now, probably at some point in the
future)
2. It violates current privacy regulation (e.g. GDPR; right
to be forgotten);
3. it is also not efficient as an identity is dynamic (attributes
can change over time e.g. house address or number of
children).
When working in digital identity and
identity management with blockchain, it’s extremely
important to always keep in mind that:
No personal data should ever be put on a blockchain.
When using a Blockchain Identity Management system what exactly goes on
the Blockchain?
Only references and the associated
attestation of a user’s verified credential are put on the ledger.
Privacy
can be ensured through non-correlation principles via pseudonymisation.
So, instead of storing actual private information, the only things stored on
the ledger (for the purpose of verification) are:
1. Public Decentralised Identifiers (Public DIDs) and associated DID Descriptor Objects (DDOs)
with verification keys and endpoints.
o
DIDs are a new type of unique
identifiers for verifying digital identities, and
are entirely controlled by the identity owner. DIDs are
independent of centralised registries, authorities or
identity providers.
2. Schemas.
o
The formal description for the
structure of a credential.
3. Credential definitions.
o
The different (often tangible) proofs
of identity or qualification issued by authorities; such as drivers licenses,
passports, identification cards, credit cards, etc. Hence, credential
definitions are — as the name suggests — merely the
definitions of these different credentials to be stored on the ledger.
4. Revocation registries.
o
An option for issuers to be able
to revoke the claim. The revocation registry is what tells the rest
of the world how the issuer will publish the revocation information.
5. Proofs of consent for data
sharing.
o
In order to prove consent or reception
of data (basically saying the data has been received and checks have been
executed on it), these consent receipts (i.e. proofs
of consent) let people do so.
Decentralized Identifiers:
The next big thing in Identity Management with Blockchain.
· DIDs are a new type of unique identifiers for verifying
digital identities, and
are entirely controlled by the identity owner. DIDs are independent
of centralised registries, authorities or identity
providers.
· According to Phil Windley,
Chairman at Sovrin, DIDs should
have the following properties:
· Decentralized identifiers should be non-reassignable. They should be permanent.
Other identifiers, such as IP address or email address, can be reassigned to
other entities by whomever is in control. This reduces privacy and security.
· Decentralized identifiers should be resolvable.
Each DID resolves to a DID Document that states the “public
keys, authentication protocols, and service endpoints necessary to initiate
trustworthy interactions with the identified entity” (source). Through
the DID Document, an entity should understand how to use that DID.
· Decentralized identifiers should be cryptographically
verifiable. Through the use of cryptographic
keys, a DID owner can prove their ownership of the DID. The public key
contained in the DID Document can also be used to attest to the
authenticity of the issuing authority’s signature associated with a credential.
· Decentralized identifiers should be decentralized.
Current identity management systems rely on centralized registries.
Each of these registries ensures trust. DIDs do not depend on a
central authority. Distributed ledger technology ensures trust as it allows
everyone to have the same source of truth about the data in
the credentials.
What if I need to change something?
Revocation
(Cancellation) in Blockchain Identity Management.
· Next to checking the attesting party, verification of a
credential also includes checking the validity of the attestation itself. The
validity of the attestation, meaning the accuracy and can be validated
through a so called revocation registry.
· The registry contains the status of each credential, whether it has been
revoked (deleted or updated) and hence whether this specific credential is
still valid.
· In other words, the ledger enables everyone in the network to have the
same source of truth about which credentials are still valid and who attested
to the validity of the data inside the credential, without revealing the actual
data.
The scenario
>“This is my drivers
licence”
>> “Says who?”
>“Says them”
>> “Who are they
and do I know I can trust them?”
+
>> “Do they
still agree/attest to this or have they changed their judgement?”
>“Yes they have not revoked their
attestation up to now”
· Revocation means deleting or updating a
credential. The possibility for an issuer to revoke a credential is crucial to
an identity infrastructure for the main reason that identities are dynamic.
· Attributes can change over time e.g. house
address or number of children, and some credentials should have a expiry date
for example a passport or drivers licence. The fact is, however, that in order to ensure trustworthiness of the
system and eliminate the possibility to defraud, credentials are immutable.
· After issuing, no one (not even the issuer) can change the information
inside the credential. Hence, when attributes change, a new credential needs to
be issued and the old one needs to be announced invalid. Thus, at each proof
the users needs to proof
that the credentials used in the proof are still valid. The revocation
registry allows him to prove this without contacting the issuing
party.
How to prevent identity fraud and identity theft if I am doing Identity
Management with Blockchain
· Through identity management with blockchain technology, each user stores
their digital identity credentials on a digital identity
wallet on his devices (like his mobile phone). Which begs the question: what if
his phone is lost or stolen?
· According to Sovrin, there are two steps to be
taken.
· The first one is to revoke the device’s authorization to use
credentials. Digital Identity credentials are only valid if
used from a device that was authorized to do so. If a user’s phone is lost or
stolen, that user could use another authorized device, like his laptop, to
write on the blockchain that his mobile phone’s authorization is now
revoked.
· This would take immediate effect and stop anyone from using the digital identity
credentials on the phone. The thief would not be able to impersonate
the user even if he has her passwords, biometrics or
phone because the blockchain, immutable and secure, would contain a revocation
registry for the phone.
· Revocation of the device’s authorization
impedes the thief to impersonate the user to create new relationships. The
second step impedes the thief to explore the existing relationships between the
device and other people or organisations. The second step thus is to revoke
the existing relationship keys (pairwise connections where each of
them has a unique key).
· These two steps stop an identity thief to use digital identity credentials
to access new services or explore relationships with existing ones. While
conveniently letting the user still use his credentials on another device.
· In many current cases, if users wished to cancel a stolen identity card,
they would have to physically go to the municipality or governmental
department, cancel that card and make a new one from scratch. Which would take
time and still would not impede an identity thief from using your data. In the
case of a stolen credit card, users will call the bank (which still takes
considerable time) and won’t be able to use the card
until a new one is issued and sent to him.
·
Sovrin have published a pdf with a thorough explanation on the
technical aspects of device loss of theft that we recommend.