Identity Management in Internet of Things with Blockchain

213

transactions in the network, each cryptographically chained with the next. The peers

are responsible for running the necessary code and coming to a consensus regarding

actions changing the ledger only through additions and never by deleting something

that is already there.

Cryptographic techniques are vital for building trust between the unknown partic-

ipants of the system [10]. Except for their use in binding the ledger blocks to form

a chain, cryptographic tools and protocols are used in order to provide anonymity

through private keys, which are held by every entity participating in the network.

These keys provide anonymity as they are usually never combined with personal

attributes, as well as the validity and authorization of any entity to interact with the

network and change the ledger’s state of data.

Lastly,governanceisaconceptrathernewfortheblockchainworldbut,ultimately,

of extreme importance when it comes to building a hierarchy of trust and managing

permissions and actions within an environment. Governance is used for applying

rules and policies in decision-making within a closed environment where different

actor roles exist.

1.4

The Benefits of Blockchain-Enhanced IAM

The current identity and access management mechanisms do succeed in providing

the functionality needed for IoT identification of users and devices, however, the

scalability of devices, services and applications are being cut off by the limitations

of those mechanisms. A single IdP can only offer so much, while at the same time the

centralization of IAM systems, working as centralized authorities, makes the whole

IoT system vulnerable as they constitute a single point of failure (SPF). A more

decentralized approach is less demanding in terms of performance for completing

the tasks of IAM, while at the same time an identity can be validated and authenticated

by any node from the blockchain network [11].

A blockchain-enhanced solution has the ability to natively remove any intermedi-

aries (such as an IdP) or any service provider for that matter, whether it relates to IAM

or not. Consequently, the interaction of users and devices, at least for authentication

purposes can become more immediate and independent of a single service. It is worth

noting that the removal of these services and their replacement with a blockchain

network does not compromise security or privacy; on the contrary, it increases them

by adding more cryptography algorithms and anonymity [12] (Fig. 2).

The immutability of the ledger can benefit the integrity of the logging process

for the devices’ interactions. Moreover, by giving the ownership of their identity to

the users, they gain full control and management over their identity as well as the

visibility of the data related to them. An example of such an implementation is the

uPort short demonstration via the uPortlandia Demo [13]. In this demo, the user is

called to download and use the uPort wallet application and go through the process

of issuing a driver’s license or a university diploma. Afterward, the user can choose

to use one of the services offered in uPortlandia, but in order to do that they must