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Blockchain Based Decentralized
Authentication and Licensing
Process of Medicine
Muhammad Azeem, Zain Abubaker, Muhammad Usman Gurmani,
Tanzeela Sultana, Abdul Ghaffar, Abdul Basit Majeed Khan,
and Nadeem Javaid(B
)
COMSATS University Islamabad, Islamabad 44000, Pakistan
nadeemjavaidqau@gmail.com
Abstract. Counterfeit medicines are increasing day by day and these
medicines are damaging the health of people. Drug Regulatory Author-
ities (DRAs) are trying to overcome this issue. Synchronized electronic
medicine record can mitigate this risk. We proposed a decentralized
Blockchain (BC) based medicine licensing and authentication system to
stop production of counterfeit medicines. Our proposed system provides
a convenient way to register medicines by manufacturers with DRA. Ven-
dors will also be registered with DRA, they are intermediate who buy
from manufacturer and sale to customers. Furthermore, every transaction
between manufacturer and vendor will be saved to BC. We used Proof
of Collaboration (PoC) as a consensus mechanism, the manufacturer
deals with more vendors will have more mining p ower. DRA has a dif-
ferent department, i.e., Licensing Department (LD), regulatory Depart-
ment (RD), and Quality Control Department (QAD). These departments
perform many actions, which will be saved in the BC database. LD reg-
isters manufacturers and vendors, RD imposes rules and QAD makes
random checks to test the quality of medicines. We also propose manu-
facturer profile scheme, QAD rates manufacturer according to its qual-
ity of medicines from the feedback of users. Moreover, we provide an
interface to the users, through which they can check the authenticity of
medicine. We compare results of traditional licensing system with BC
based licensing system.
Keywords: Blockchain ·Decentralized ·Authentication ·Licensing ·
Data security ·Medicines network ·Verification ·Consensus
1 Introduction
In the modern era, counterfeit medicines are still a serious issue. These coun-
terfeit medicines are not only damaging the patient’s health, rather, it is also
a dismal reflection of society. The manufacturers who formulate the counter-
feit medicines, put patient’s life on risk as well as they are responsible for tax
c
Springer Nature Switzerland AG 2020
L. Barolli et al. (Eds.): 3PGCIC 2019, LNNS 96, pp. 355–366, 2020.
https://doi.org/10.1007/978-3-030-33509-0_32
356 M. Azeem et al.
evasion, pollution, unemployment and child labor. To overcome these issues, lit-
erature is full of ideas, models, and processes by which medicine can be traceable,
authenticate and minimize the production of counterfeit medicines.
With to increasing number of medicines, the Drug Regulatory Authority
(DRA) made lot of rules and trying to fully implemented these rules to over-
come on counterfeit medicines. Departments under drug regulatory authority
are: (1) Licensing Department (LD) (2) Regulatory Department (RD) (3) Qual-
ity Assurance Department (QAD). These department are working in unsynchro-
nized environment, due to which efficiency and traceability are unsatisfied. How-
ever, strict and unimplemented regulation and inefficient bureaucratic job are
also a huge reason in the production of counterfeit medicines. All these depart-
ment have their own different database and asynchronous communications. This
asynchronous communication makes beneficial for counterfeit medicine’s manu-
facturer, in the formation of bogus and low quality medicines. Once, a manufac-
turer reaches to LD for register a medicine, LD does not have enough information
to see the history of a manufacturer, its previously registered medicine and the
quality of medicine it is producing. Also, QAD do not have enough information
of registered and currently producing medicine of manufacturer.
Vendor is an entity of this system, which buying medicines from manufacturer
and selling to user. Mischievously, vendor are not registered with the DRA. So,
some vendors are selling counterfeit medicines with the cooperation of bogus
manufacturers.
There is a need of synchronous distributed database, which provides data
efficiently and correctly with security. In the medicine domain, LD should have
access to view history of the manufacturer, its quality reports and overall
progress before issuing a new license of medicine. QAD should also have access
to know about all licensing products of a manufacturer and it should be able to
check currently manufacturing medicine. Blockchain is now emerging and one of
the disruptive technologies, providing the most beneficial and secure mechanism
to trade between entities without any centralized party. Besides, high security
and reliability make Blockchain (BC) more convenient to use in every field of
life. A decentralized BC based medicine licensing and authentication system per-
forms better than centralized asynchronous database. Moreover, asynchronous
data can be stolen or temper in any way, whereas, BC based decentralized data
is very hard to stolen and tempered. Although, every entity of BC has a copy
of the database if any hacker will try to tempered data, others have a copy of
original data to mitigate this issue.
For controlling counterfeit medicines, our contribution is summarized as fol-
low:
1. We proposed a decentralized BC based database for medicines, in which
license issues to the manufacturer which will be validated by the miner.
Other manufacturers act as miners and validate new license with Proof of
Collaboration (PoC) as a consensus mechanism. The manufacturer deals with
more vendors has more mining power. Also, decentralized database enables
all departments to check medicine license and authenticity at real time.
Blockchain Based Decentralized Authentication 357
2. We proposed profile scheme by which synchronous database allows to all
the entities like DRA departments, manufacturers, vendors, and users to see
manufacturer and vendor’s profile. QAD rates the profiles of manufacturer
and vendor from the feedback of user. Furthermore, the license would be
canceled if manufacturer and vendor do not maintain their profile rating
according to the threshold level set by DRA.
3. We use smart contract to impose rules, by which both parties will be agreed
on rules and regulations. The violation of rules and regulation would affect
the manufacturer’s profile as a negative rating.
4. We provided an interface for users to verify the medicine authenticity and
quality. On the interface, user input medicine license and transaction number
performed between user and vendor, in result user will get all detail about
medicine. User will rate manufacturer and vendor’s profile according to his
satisfaction.
2 Related Work
With a lot of research in the interoperability of health-care and medical data,
there is little research in medicine authentication and licensing [1]. In [2] author
discussed openEHR interoperability standard and explained the OmniPHR
model, due to a lack of interoperability standard medical and health-care data
very difficult to integrate. In [3] explained the medical information sharing with
BC, dealing with data security and controlled sharing. Also, precautions of inap-
propriate handling of medical and health-care data lead to personal identity
leakage, insurance fraud, and personnel data misused. The procedure of patients
from contact with a doctor to buy medicine is explained in [4] with the applica-
tion of BC. In [5] author proposed a model MedRec, a BC based model for saving
the medical record and health-care data. Further, it determine the security and
privacy of the system during the record access. Blockchain based networks are
based on Internet of Things (IoT), every entity in the network have IoT device
for different functionality.
With the increasing number of IoT devices, there are a lot of issues in con-
nectivity, security, privacy, scalability, and robustness of a network. Blockchain
in [6–8], are used to tackle different problems. Different types of BC are used
in different scenarios, like in [7,9] used consortium BC, in [6,8] public BC is
used. Furthermore, in [6,8] consensus mechanism, PoW is used while in [9]proof
of authority and in [7] PBFT are used. In [9] author proposed a model for
secure lightweight clients and validity states of source for prevention of mali-
cious attacks.
Networks are limit in resource sharing, every node in the network needs to
connect and should remain active for operations. With the increase in the data
set and increasing size of the application, networks are not more efficient and scal-
able. To achieve secure, reliable, scalable and robust networks [10] used BC. Con-
sensus mechanism Proof of Work (POW) is used in [11–14] and proof of collabo-
ration (PoC) is used in [12,15] which increase the security of network and reduce
358 M. Azeem et al.
the entry of malicious nodes. Ethereum environment for transactions are used
in [13–15] which provides an authentic way to transfer incentive from one node
to another. Data is indisputable, tamper-proof and decentralization with PDP
consensus mechanism [10]. Decentralized storage, spectral efficiency Q-learning
and exhaustive learning mechanism increase the connectivity of live users with
disconnecting the sleeping node [11]. In paper [10] POW, electronic signature,
point to point network, hashing algorithm and distributed ledger decrease pol-
lution attacks and bloating problems. Multi layer access in mobile devices and
transport networks are proposed for scalable and secure access data from data
centers [12].
Different sensing devices spreading very fast to sense data, manipulate and
broadcast it, i.e. temperature devices are connected in a network with different
manners to sense temperature and send it to the network for further analysis.
Due to their very low power, storage, and computation resources, they cannot
defend themselves from attacks of malicious devices. Wireless sensor nodes are
connected through BC and used different consensus mechanism in [17–20]. Prov-
able data possession and hash rate are used in [17] along with the problem of the
selfish node. In [18] virtual credit, privacy protection, and confusion mechanism
made secure and reliable data sharing.
3 Traditional Approach
Traditionally, licensing and quality control of medicine are done by a centralizing
manner by DRA as shown in Fig.1. When DRA issues the license to manufac-
turer it will verify the information only one time. Manufacturers, at the start,
contact to the LD for registering a medicine in order to manufacture it [22].
LD will issue the license to that manufacturer who will have a proper place,
instruments, and expertise in manufacturing. LD ensures all these requirements
then allows manufacturer to produce medicine with a license number. The need
of license against a medicine is not only necessary for manufacture a medicine,
while it is also used for regulating medicine through out the process. License
ensures that specific medicine are manufacturing under properly, safe and good
condition [23]. So, RD is playing a role to impose different rules and regula-
tions on different medicine with different characteristics. Some manufacturers,
do not follow the rules, produce low quality medicine in a bad environment.
QAD has the right to check a manufacturer that the medicine it producing have
good quality and made under following the proper rules. Vendors does not know
about manufacturer while purchasing the medicine, so there is chance to buy
counterfeit medicine and then sell it to user. Users do not know about legality,
quality, and cost of medicine [24].
In traditional system, the process of imposing penalty due to low quality and
counterfeit medicine is very slow. There is no back tracking system for medicine
to maintain the quality of medicine. Further, there is no way to check a medicine
by user.
Blockchain Based Decentralized Authentication 359
Fig. 1. Centralized system of authentication and manufacturing medicine
4 Architecture
DRA issues the license to the manufacturer through smart contracts against a
medicine as shown in Fig. 2. In BC, medicine license broadcasts to the network,
miners check eligibility of specific manufacturer. Once, a manufacturer will be
able to purchase a license, some amount as Ethereum will be deducted from
his account to DRA’s account. Every action from DRA like quality checks and
rules applying, will be saved into manufacturer’s account. Like, the polluted
environment and poor quality penalty imposed through the smart contract and
will be written in manufacturer’s profile after miner validation.
DRA: To register a medicine, every specific area has its own DRA, which deals
with medicine related challenges, quality, rules and facilitates manufacturers
with new medicine manufacturing technology. The focus of DRA is discussed in
this paper, is to stop the manufacturing of counterfeit medicines and provide a
secure way to check medicine’s authenticity. Functionality of DRA departments:
•LD: Medicine licensing is the first step for a manufacturer in order to get
permission from DRA to manufacture medicine. Manufacturers provide all
evidence about the ability of production of medicine, packing and storing. LD
will analyze manufacturer pre-production steps and the history of previously
manufactured medicines. The manufacturers, with good pre-production steps
and having a good record of previously manufactured medicine, are able to
get the license of a particular medicine.
•RD: Every medicine has different production processes, packing constraints
and ways of storing. Some medicines will be stored in freezing temperature
and some will be stored at room temperature. Medicine packing processes and
packing material also have some constraints. So, every medicine production,
packing and storing related rules and regulations are imposed by the RD.
Furthermore, these rules are continuously changed with the new technology
evolves.
360 M. Azeem et al.
•QAD: This department ensures that the rules and regulations are followed by
the manufacturers. With the use of IoT devices QAD can check quality mea-
sures of manufacturing processes. It is easy way to identify a manufacturer
which will not following the rules. Once, a manufacturer with bad activities
identifies, QAD will impose a penalty on him. Some amount as Ethereum will
be detected from the manufacturer’s account. Also, profile rating of manu-
facturer will be decrease. QAD have right to cancel the license of any culprit
manufacturer.
Vendor: The vendor is the intermediate entity between end-user and manufac-
turers. Manufacturer after manufacturing medicines sales to the different ven-
dors through the smart contract. Vendor ensures first about the authenticity of
medicine by looking manufacturer profile and check license number that belong
to related manufacturer. Then, vendor purchases medicines through smart con-
tract and responsible for further storing these medicines in good quality environ-
ments. Vendors are registered with DRA, now every transaction between vendor
and manufacturer, will be saved in the database of BC. Now, DRA can easily
verify about the manufacturer and vendor, which are making transaction.
Once, a vendor enters the network, it is hard to sell counterfeit medicines,
due to maintaining profile rating. If any vendor will involve in selling counterfeit
medicines, Once a user will purchase that medicine and check it by interface.
Then, user will report about culprit vendor and DRA will cancel vendor’s license.
End User: Patients are the ones who will use the medicines, they are not
well known about manufacturers. They mostly doubtful about medicines, while,
these medicines are formulated by authorized manufacturers, well packed and
came from a good environment. To mitigate this issue, our proposed system
provides an interface to end user. On which users input medicine license and
transaction number, all details about medicine like manufacturer name, formula,
batch number, will display on his interface.
Smart Contract: The smart contract, basically, is a code written in a program-
ing language. It has a set of rules, which will be broadcast to network, when two
parties agreed upon a situation. A smart contract does not change once it will
be broadcasted to the network. The penalty will be imposed on nodes, which
agreed on a smart contract and later break rules written in the smart contract.
5 Methodology
5.1 Blockchain
BC is a technique which used in the decentralized network, for maintaining a
consistent database among distributed members. Firstly, Satoshi Nakamoto used
this technique in well-known currency, i.e., Bitcoin [25]. The BC based decentral-
ized network has no single fixed database, while in the centralized network, data
has to be stored in a single fixed database. In the public BC, all members are
Blockchain Based Decentralized Authentication 361
miner and perform mining while adding a block in the BC. In the consortium
BC, the network is classified into different layers and a specific layer has the
right of mining. A private BC has a limited number of nodes, and only selected
nodes will behave as miners. Miners are that nodes in the network, which solve a
mathematical task to validate a transaction. Due to every node has a copy of the
BC, no one can change data stored in the BC unless it has strong computation
power. If anyone have such computation power it can be able to hack 51% nodes
then it can control mining which is not possible. Because of this ability, BC is
widely studied in research nowadays.
Blockchain is consists of blocks that are arranged in a specific order, each
block has a number of transactions. These transactions are generated by traders
and after successful validation, transactions broadcasted to the entire network.
Blocks are chained in a way that every block address has some value of the
previous block, i.e., the hash value. The change in any block address would
change the entire BC address. Furthermore, a nonce is added in the block, which
is the mathematical problem. A miner which will efficiently solve the nonce, will
considered as centered node and broadcast his block. Miner election schemes,
e.g., POW, proof of capacity, proof of stake use computation power, storage
capacity and capital respectively to elect a node as a miner. Consequently, BC
is more successful in providing data security in decentralized manners.
5.2 BC Based Design Overview
In our proposed model, the BC based database used for saving medicine records.
Manufacturers apply for a license through smart contract, they write pre-
production preparation, and agreements that they will never misuse this license.
In pre-production preparations, manufacturer will describe location, produc-
tion material, and expertise of production. DRA checks its eligibility and pre-
production preparation, then send manufacturer record for validation. In the
consensus PoC, all miners will check manufacturer’s profile, if the previous rating
is good then miners validate the profile of manufacturer. After validation, DRA
allows the manufacturer to formulate the medicine and issues a license number
against the medicine. The rules and regulations are also applied through the
smart contract. Once, a manufacturer agrees on rules and regulations, data will
be saved in the BC. Now, QAD checks manufacturer’s production processes fre-
quently and randomly. The manufacturers violating the rules would be charged
with a penalty as a Ethereum. Continuously, violation of the rules would have to
cancel the license by the DRA and manufacturer would no longer to formulate
any medicine.
Vendor registers with DRA through the smart contract, on which medicine
storing preparations are written. DRA analyses first storing preparation and val-
idates vendor by miners. Vendors are also possessed profile on which their rating
is mentioned. Once, QAD identifies a vendor violates rules or sales counterfeit
medicines, the vendor’s registration would be canceled, and it would no longer
be the part of the network. Otherwise, penalty would be imposed on breaking
the rules.
362 M. Azeem et al.
Fig. 2. Decentralized system of authentication and manufacturing medicine
5.3 Advantage of BC Based Authentication
Dece ntralized: Traditionally, DRA using asynchronous centralized database
by which counterfeit medicine manufacturers can easily be advantageous. If any
department of DRA has lost its data or data compromised, no way to recover
it. Our decentralized BC based database, are synchronous, reliable, secure, and
transparent. Due to every node have a copy of the BC, attacker will be able
to hack only small portion of network. Practically, they would not succeed to
overcome the network, because data is distributed on every node.
Tamper-proofin g: The malicious user would try to add its block of transactions
or bogus license numbers via compromising a node. Due to distributed manners
of BC and use of consensus mechanism, its transaction will be rejected by miners
and it also do not be able to add a block in the BC.
Consistency: By maintaining the record in the BC based database, every time
it returns the same results. Whenever, a user would buy a medicine from the
vendor, and check its validity by interface. Medicine will be reflecting its own
manufacturer name and license number.
Timeliness: Based on POC, all manufacturers would be able to add their blocks
into the BC. Like, a manufacturer have more trust points, which based upon valid
transactions with multiple vendors, would more likely to win a nonce and add a
block in the BC.
Availability: Data stored in BC can be accessed by all entities in the network.
Whenever, a user purchases a medicine, he checks validity by the interface. On
every inquiry of medicine, BC will instantaneously respond.
Blockchain Based Decentralized Authentication 363
6 Workflow of Proposed System
Our proposed system in Fig. 2, describes the processes of BC based decentralized
licensing and authentication process. Following are the steps of our proposed
model, i.e., (1) Drug licensing and rules applying; (2) Rating of manufacturers
and vendors; (3) Manufacturer and vendor dealing; (4) Customer application
interface.
Step1 : Drug licensing and rules applying: Drug licensing procedure for the man-
ufacturer is very easy in BC. Due to introducing smart contract in our system,
all activities will perform through the execution of the smart contract. Manufac-
turer will write a code of smart contract, in which preproduction preparation,
material and relevant expertise of medicine will be written.
LD analyzes preproduction preparation, availability of material ans relevant
expertise of manufacturer. Then, manufacturer’s smart contract will be broad-
casted for consensus. With the POC, miner will validate the manufacturer’s
smart contract according to his profile rating. Other manufacturers as a miner
will authenticate new license manufacturer. After 51% of miner authentication
for a manufacturer, it is successfully eligible to get a license of medicine. With
consensus mechanism, no bogus manufacturer could be entered to network. Also,
manufacturers with negative ratings would not be part of the network. LD broad-
cast nonce for a miner with a threshold level, the manufacturer with more valid
transactions with vendors, has a large number of chance to meet threshold level.
For vendor registration, vendor will broadcast a smart contract in which it
will code followed rules for storing medicine and agreement for selling authen-
tic medicines. LD analyses the smart contract and send for miner validation.
Vendor’s profile will checked by miner and according to profile rating miner will
validate. Negative rating vendors will not be successful in miner validation.
Step2 : Rating of manufacturers and vendors: For the new manufacturers and
vendors, LD adds default rating to their accounts, e.g., for manufacturers ten
is the highest rating by default and for vendor number three is highest rating.
Manufacturers have high rating than vendors because QAD imposes penalty on
manufacturers by many factors whereas vendor have only environmental or stor-
ing factors. Manufacturer’s factors are environmental, technological, expertise,
and cleanliness.
Step3 : Manufacturer and vendor dealing: Previously, manufacturer and vendor
dealings did not save in DRA’s record. Now, the vendor broadcasts a smart
contract when it needs to buy any medicine, whereas, manufacturer broadcasts a
smart contract about selling manufactured medicines. When both parties agreed
on a contract, they made the transaction, which broadcasted to network for
mining.
Miner will check the profile rating of manufacturer and vendor, transaction
will be successfully validated when both parties will have positive rating. In
our proposed system, we achieve more clarity that manufacturer with negative
profile can not sale its medicines and vendor with negative profile can not buy.
364 M. Azeem et al.
Highly rating vendors would prefer to deal with highly rated manufacturers.
In this way, manufacturers and vendors always maintain their high ratings for
selling and purchasing.
Step4 : Customer application interface: In traditionally, there was no way to
determine the authentication of medicine by the customer. The proposed model
provides an interface to the customer, on which customer input license and
transaction number that he performed with the vendor and get all details of
medicines. Moreover, counterfeit medicine would not have any record, and the
customer will receive an attention message. On the interface,customer would
complain to DRA if the medicine is bogus, by clicking on complaint button.
7 Results and Discussion
Before introducing BC in medicine licensing and authentication processes, these
processes were slow, time-consuming, insecure and unreliable. There was no data
synchronization within DRA, anyone could be temper record for his own purpose.
Bogus license, un-implementation of regulations and lack of quality checks on
manufacture were the issue faced in traditional system. Users did not know about
medicine while is it valid medicine or not, due to asynchronous data.
Our proposed system provides data security, integrity, scalability, and effi-
ciency. Hacker can not access data for long because data have to be saved on the
distributed BC based ledger, when data have to be tempered on one end, other
ledgers have the same data as the original. Due to every transaction validated by
consensus mechanism, miner check profile rating first and then validate a trans-
action. Every medicine validates three time in the whole process, first in issuance
of license, then in purchasing by vendor and finally, when user purchased from
vendor.
Figure 3shows the results of license issuance with respect to time. Results
show that BC based system is very efficient and less time consuming with respect
to the existing system. The existing system consumes more hours to complete a
task than our proposed system.
Figure 4shows the results of transactions per day, our proposed BC based
system can perform well and a huge number of transactions can perform. In
the existing system, transaction performed manually with out smart contract.
In proposed system, smart contract used for every transaction where all entities
can work efficiently.
Business established due to earn profit in less time. Figure 5shows the cost
of transactions. Through decentralized BC based database with smart contracts
reduced transparency cost, security cost processing cost, storage cost, and com-
munication cost. Existing system has different types of hidden cost as well.
Blockchain Based Decentralized Authentication 365
Fig. 3. License issuance in blockchain vs traditional system
Fig. 4. Number of transaction in blockchain vs traditional system
Fig. 5. Cost of transactions in smart contract vs third party
8 Conclusion
In this paper, we proposed BC based decentralized medicine licensing and
authentication system. The manufacturer will request by smart contract to
apply for licensing, Smart contract is used for applying licensing, imposing rules,
quality checks and receiving penalty. User also use smart contract to verify the
authenticity of medicine. Finally, the vendor is now registered with DRA and
part of the network for any transaction.
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