Blockchain for IoMT: A Technical Review
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on a set of attributes including the credentials, role and the domain. It uses
IPFS for data storage. An interPlanetary File (IPFS) is used to store patient
health records and devices technical information. The consensus mechanism is
performed by a smart contract. The authors proposed a proof of medical stack
(PoMS) as an alternative to PoS consensus model to protect smart contracts
from malicious actions. PoMS allows stakeholders with huge amount of medical
data presented as tokens to validate and create blocks.
A private blockchain-based system for medical data management has been
proposed in [9]. It works on Ethereum smart contracts to manage data access
permission between entities including patients, hospitals, doctors, research organizations and other stakeholders. The smart contract contains smart representations of medical records including permissions, record ownership metadata and
data integrity. The medical record data are stored in external server (off-chain)
and a cryptographic hash of the record is kept on the blockchain ensuring data
integrity. The proposed system eliminates mining for simplification.
In [3], authors developed a cloud-based framework to monitor the progression
of a neurological disorder disease using IoMT devices. They used cloud computing to store and process IoMT data and deploy Ethereum-based Blockchain
network to securely exchange and share data between healthcare users. Smart
contracts are employed to control users access to data in the cloud. No technical
details about integrating blockchain in the system are presented.
In [6], authors proposed a permissioned blockchain-based architecture for
secure remote patient monitoring. They used Ethereum to implement smart
contracts in order to analyze data and send alerts to patient and healthcare
providers. They proposed the use of Practical Byzantine Fault Tolerance (PBFT)
as an alternative to PoW consensus model. The proposed architecture lacks
techniques to meet challenges related to IoMT-Blockchain integration. And in
SMEAD [13], an Ethereum-based architecture for remotely monitoring diabetes
patients, smart contracts are used to manage access to data.
3.2 Modified Consensus Protocol
In order to fit the IoMT specificities, some works like [12] have proposed to modify the consensus protocol. In [20], authors proposed a consortium blockchainbased architecture in order to record data generated from IoMT in a secure
way while ensuring the patient’s privacy. The proposed architecture implements
a patient agent software (PA) that defines the Blockchain functionalities. It is
deployed on the Edge computing network to perform lightweight tasks and on a
cloud server to provide tamper proof storage of the large volume of health data.
The authors also proposed a modified PoS consensus which consists in choosing
a leader for a group of nodes to validate and create the blocks. Smart contracts
are used to manage health data including filtering clinically useless health data,
generating alarm for some events, migrate data to the cloud if necessary, classify
data and others. Compared to PoS, authors affirm that the modified PoS is more
efficient in term of energy consumption and block generation time.
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on a set of attributes including the credentials, role and the domain. It uses
IPFS for data storage. An interPlanetary File (IPFS) is used to store patient
health records and devices technical information. The consensus mechanism is
performed by a smart contract. The authors proposed a proof of medical stack
(PoMS) as an alternative to PoS consensus model to protect smart contracts
from malicious actions. PoMS allows stakeholders with huge amount of medical
data presented as tokens to validate and create blocks.
A private blockchain-based system for medical data management has been
proposed in [9]. It works on Ethereum smart contracts to manage data access
permission between entities including patients, hospitals, doctors, research organizations and other stakeholders. The smart contract contains smart representations of medical records including permissions, record ownership metadata and
data integrity. The medical record data are stored in external server (off-chain)
and a cryptographic hash of the record is kept on the blockchain ensuring data
integrity. The proposed system eliminates mining for simplification.
In [3], authors developed a cloud-based framework to monitor the progression
of a neurological disorder disease using IoMT devices. They used cloud computing to store and process IoMT data and deploy Ethereum-based Blockchain
network to securely exchange and share data between healthcare users. Smart
contracts are employed to control users access to data in the cloud. No technical
details about integrating blockchain in the system are presented.
In [6], authors proposed a permissioned blockchain-based architecture for
secure remote patient monitoring. They used Ethereum to implement smart
contracts in order to analyze data and send alerts to patient and healthcare
providers. They proposed the use of Practical Byzantine Fault Tolerance (PBFT)
as an alternative to PoW consensus model. The proposed architecture lacks
techniques to meet challenges related to IoMT-Blockchain integration. And in
SMEAD [13], an Ethereum-based architecture for remotely monitoring diabetes
patients, smart contracts are used to manage access to data.
3.2 Modified Consensus Protocol
In order to fit the IoMT specificities, some works like [12] have proposed to modify the consensus protocol. In [20], authors proposed a consortium blockchainbased architecture in order to record data generated from IoMT in a secure
way while ensuring the patient’s privacy. The proposed architecture implements
a patient agent software (PA) that defines the Blockchain functionalities. It is
deployed on the Edge computing network to perform lightweight tasks and on a
cloud server to provide tamper proof storage of the large volume of health data.
The authors also proposed a modified PoS consensus which consists in choosing
a leader for a group of nodes to validate and create the blocks. Smart contracts
are used to manage health data including filtering clinically useless health data,
generating alarm for some events, migrate data to the cloud if necessary, classify
data and others. Compared to PoS, authors affirm that the modified PoS is more
efficient in term of energy consumption and block generation time.