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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Ensuring the Security of the Full Logistics Supply Chain Based on the Вlockсhain Technology</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>National Aerospace University “Kharkiv Aviation Institute”</institution>
          ,
          <addr-line>Chkalova Str. 17, 61070 Kharkiv</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>National University of Civil Defence of Ukraine</institution>
          ,
          <addr-line>Chernyshevska Str. 94, 61023 Kharkiv</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <fpage>0000</fpage>
      <lpage>0002</lpage>
      <abstract>
        <p>Issues related to ensuring the security of the functioning of the full logistic supply chain of dried fruit (SCDF) in Ukraine are considered. It is shown that the creation and function of the SCDF, compared to other supply chain management (SCM) class systems, raises a number of specific problems caused by the complexity of the interaction of raw material suppliers (fresh fruit), manufacturers of final products (drying, packaging), storage terminals, distributors, 3PL and 4PL providers (retailers). These problems are due to the fact that the interaction of participants in business processes in the SCDF generates a lot of material, financial and information flows, as well as flows of services from sources of raw materials to the final consumer. An important aspect of improving the performance of the SCDF is the development of methods and tools, and on their basis the applied information technology to ensure the reliability and security of the SCDF. To solve this problem, it was proposed to use the Blockchain technology to protect the telecommunication channels connecting the circuit elements from unauthorized access. The method of identification and authentication of digital objects of the SCDF, which guarantee the security of SCDF elements and provide them with the necessary level of confidentiality, is described.</p>
      </abstract>
      <kwd-group>
        <kwd>Full Logistics Supply Chain</kwd>
        <kwd>Security of the IoT-Objects</kwd>
        <kwd>Blockchain</kwd>
        <kwd>Authentication of IoT-Objects</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        reflected by the multitude of material, financial and information flows, as well as the
flows of services from sources of raw materials to the final consumer. These features
determine the specifics of this subject area, namely, a relatively large number of
participants in business processes and, accordingly, the complexity of the
telecommunication structure of SCDF. Due to this circumstance, there are increased risks of
unauthorized access to the SCDF communication channels by competitors. The variety of
world regions from which dried fruit is delivered to Ukraine, a wide range of products
supplied, yield, currency fluctuations, seasonality are the causes of a high level of
uncertainty in the processes of formation and decision-making by the SCDF
participants [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>
        These circumstances determine the lack of effectiveness of the existing SCDF and
dictate the need to modernize it by expanding the concept of supply chain
management (SCM) [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] by supplementing it with Internet of Things (IoT) objects, which will
make it possible to achieve a conjunctive consensus between all elements of the
SCDF in its functioning [
        <xref ref-type="bibr" rid="ref5 ref6">5, 6</xref>
        ].
      </p>
      <p>
        A prerequisite for effective management of SCDFs is coordination of joint
activities of SCDF participants and synchronization of their business processes, which
ultimately is achieved by increasing efficiency: formulating goals and objectives of
SCDFs, developing an action strategy based on in-depth and comprehensive analysis
of the supply market (including the requirements of a specific customer) and the
current state of the supply chain of dried fruit in Ukraine. The fulfillment of this
condition is possible only if the appropriate level of protection of digital objects, which are
part of the supply chain, is ensured from unauthorized access [
        <xref ref-type="bibr" rid="ref7 ref8 ref9">7 - 9</xref>
        ].
      </p>
      <p>The purpose of the article is to present an approach to ensuring the security of
digital objects in the SCDF, presented in the form of IoT, based on a special procedure
involving the integrated use of certain software platforms within Blockchain
technologies.
2</p>
      <p>
        Ensuring the Protection of IoT Objects that are Part of the
SCDF
Security and confidentiality is part of the measures that guarantee the reliable
operation of connected IoT objects and compliance with regulatory requirements for the
functioning of SCDF. The proper level of security for the operation of the SCDF is
determined, in particular, by the high level of protection from unauthorized access to
digital objects of chain represented in the form of IoT. The most important is the
protection of such objects in the modes of identification and authentication. Identification
of the Internet of Things Objects (IDoT) is a task area for assigning unique identifiers
and associated metadata to the Internet of Things objects, which allows them to
exchange information with other entities on the Internet [
        <xref ref-type="bibr" rid="ref10 ref11">10, 11</xref>
        ].
      </p>
      <p>
        All IoT objects in the SCDF must be registered under unique and, very
importantly, constant identifiers that are assigned at the level of the control center
(focal company), and each identifier must correspond to a set of metadata - detailed
information about the IoT object determined depending on context of the functioning
of the object in the composition of the SCDF. At the same time, the set of metadata
itself is essentially a digital object with a clear structure. Thus, the identification and
authentication of digital objects that exist in the SCDF, require the development of
special algorithms, since such objects must be identified and managed. When sending
confidential information, sureness in the protection of information from unauthorized
use or disclosure by competitors is required [
        <xref ref-type="bibr" rid="ref12 ref13">12, 13</xref>
        ].
      </p>
      <p>When building a SCDF with IoT elements, there are two key security components:
the integrity and authenticity of the software of IoT objects, that is, only the software
that was allowed to work on this device is loaded; authentication of IoT objects before
they can transmit or receive information on material, financial and information flows
within the SCDF.
3</p>
      <p>
        Ensuring the Security of IoT Objects as Part of the SCDF
Using Blockchain Technologies
In recent years, the Blockchain technology is at the zenith of the Gartner Hype Cycle,
and now there are a large number of projects in which this technology is used to
organize trusted calculations, identify and authenticate objects [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]. Using Blockchain
technology to store data that has been protected with cryptographic keys gives
confidence that data will not be to forged with [
        <xref ref-type="bibr" rid="ref15 ref16">15, 16</xref>
        ]. By nature, Blockchain is a
distributed database in which storage devices are not connected to a common server. This
database stores an ever-growing list of ordered records, so-called blocks. Each block
contains a timestamp and links to the previous block. Blockchain makes intervention
almost impossible, because it requires simultaneous access to database copies at all
information processing centers in the SCDF. IoT data, Blockchain distributed
architecture and the ability to verify ownership form the methodological basis for ensuring
the appropriate level of confidentiality of business processes that occur during the
functioning of SCDFs [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ].
      </p>
      <p>A distributed account, or the registry, which is used in Blockchain technologies,
enables the ownership, transparency and general decentralization of the functioning of
digital devices in the form of IoTs that are part of the SCDF.</p>
      <p>The decentralized registries underlying Blockchain technologies are based on a
circuit where the centers of trust and control are transferred to the virtual control
network of the SCDF, whose nodes constantly record transactions in a specific order,
into publicly available blocks, thereby creating a chain (Blockchain). Each block is a
container with data that can be accessed only by the owner of the container, but any
node of the SCDF can conduct the owner authentication procedure.</p>
      <p>
        To build a SCDF, it is advisable to apply the so-called smart contracts: small
programs that are recorded along with the data block. These programs contain rules by
which data will be used. The main idea of reasonable contracts is that the parties can
independently verify operations, agreeing on the conditions. Thus, metadata,
including information about the owner of the object, can be recorded inside blocks, and
Blockchain, among other things, is responsible for the resolution system [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ].
      </p>
      <p>
        The concept of using Blockchain to ensure the security of SCDF operation is based
on three software platforms - TeleHash, BitTorrent and Ethereum. TeleHash is a
decentralized and secure peering (P2P) protocol for exchanging data and transmitting
messages over the network [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ]. Under this security concept, data and messages
transmitted using the TeleHash protocol are verified and certified by a third party;
herewith the communication model is temporary, the client-server model is not used.
BitTorrent is a peering (P2P) network protocol for cooperative file sharing, it
implements the concept of file sharing through the interaction of source clients (seeders and
leeches) [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ]. The third component is Ethereum - based on the Blockchain virtual
machine and a set of Web 3.0 services, which gives users the opportunity to work
with the software environment of reasonable contracts, developing and filling it with
content at their discretion, by supporting contract programming [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ].
      </p>
      <p>Based on the described software platforms, an environment of protected digital
objects in the form of IoT is created, ensuring the stable functioning of the SCDF. At the
same time, IoT objects within the SCDF can exchange data with each other through a
hypermedia environment and form a single global continuous chain of transaction
records, similar to Blockchain for bitcoins. The principal difference of this concept
from the bitcoin technology is that the content and types of network entries will be
determined by the contracts that will be concluded between the SCDF nodes.</p>
      <p>A rational circuit for using Blockchain to increase the level of security for SCDF
functioning will be its incorporation into the existing IoT object identification circuit
as an alternative system for resolving objects or using it as an additional center of
trust. For example, with a resolution in the system, the returned metadata may contain
a link to the corresponding block in the decentralized registry.</p>
      <p>New standards for IPv6-based protocols, such as 6LoWPAN, show that it is
possible to create an efficient circuit for assigning unique identifiers for IoT objects in the
SCDF.
4</p>
      <p>The Identification Algorithm for Iot-Objects in the SCDF
Based on the BLE/Blockchain Stack</p>
      <p>Encryption of blocks ensures that only those parts of the chain of blocks are
accessible to users for which they have private keys, without which reading or changing the
record is impossible. Encryption ensures synchronization of copies of a distributed
chain of blocks for all users.</p>
      <p>The decentralized peer-to-peer Blockchain network prevents individual
participants from controlling the core infrastructure of the SCDF or destabilizing its
operation. All SCDF participants are considered equal and are connected to the network
using the same protocols. The circuit of using the described technology for identifying
the user's rights to manage the IoT-object of the SCDF shows Fig. 1.</p>
      <p>The participant's public key (1, 2, 3) is the address itself, for managing the IoT
object.</p>
      <p>The transaction hash is a unique identifier (checksum of the entire transaction from
start to finish).</p>
      <p>The signature of the participant (1, 2, 3) - with the help of the secret key confirms
his authority as the owner of the object.</p>
      <p>The generated transaction enters the block, and, like all new transactions, is
launched into the network, where within a certain time, it will be attached to the
chain. The network, in turn, contains a large number of nodes that form the new unit
and verify the reliability of the transaction.</p>
      <p>Nodes, by computation, select a hash for the block through a direct search of
various values. When a value is found and it meets all requirements, the block is
considered formed.</p>
      <p>The application of the described algorithm ensures that all data in the SCDF is
protected. Through the information in any block you can see the entire number of
objects, but it is not possible to find out who owns them. In order to view the data, you
need to confirm ownership of this transaction.</p>
      <p>A special key is used to identify the user. In this case, the user has only one key,
which has two different properties: having the key in hand, it will not be possible to
find out the primary (source) information; it is impossible to select another data
packet that would give the opportunity to create the same key.</p>
      <p>IoT objects in the SCDF must be equipped with passive radio frequency
identifications (RFID) and bluetooth low engineering (BLE) modules to ensure object
identification and data transfer capabilities. BLE consists of two main parts: the controller
and the host. The controller includes a physical and data link layer. The functions of
the SCDF node include: the level of logical link control (LLC), the adaptation
protocol (L2CAP), the attribute protocol (ATT), the generic attribute profile protocol
(GATT), the security manager protocol (SMP); generic access profile (GAP).
Additional application layer functionality can be implemented above the host level.</p>
      <p>Using distributed registers to manage IoT objects is considered as the basic
component of the SCDF architecture to ensure confidentiality, that is, in the proposed
architecture, the Bluetooth-enabled gateway uses Blockchain technology to protect
the user from unauthorized access (Fig.2).</p>
      <p>Consider the algorithm of functioning of the gateway. This algorithm is illustrated
in Fig. 3. We divide network participants into three main types: owners or
administrators of IoT objects; gateway administrators; end users.</p>
      <p>Before the user can access the IoT device, the device administrator saves device
information and device privacy policy in the Blockchain network. In general, the device
information includes a list consisting of: a unique device name; processing relevant
information; device features, such as device type, device model name and number,
serial number, etc.; other attributes for management purposes, such as a list of device
images, a privacy policy, and services provided.</p>
      <p>Using the Ethereum platform, the IoT device administrator creates a smart contract
for the device and uses the contract to manage the information and privacy policy of
the device (step 0a).</p>
      <p>The gateway administrator creates a smart contract for the gateway (Step 0b). After
physically connecting the gateway to the IoT device, the gateway administrator will
associate the smart device contract with the smart gateway contract (step 0c). When a
user uses his smartphone to connect to the gateway (Step 1), he gets the address of the
smart gateway contract. Information on devices connected to the gateway becomes
available to the user (Step 2). Further, the user receives the address of the smart
contract of the IoT device, and controls the confidentiality through the smart contract of
the device (step 3).</p>
      <p>After receiving guarantees of confidentiality of the IoT object, the user connects to
the appropriate gateway and informs the gateway that it accepts or rejects its policy
(Step 4). After accepting the conditions, the parameters are saved in the gateway (Step
5), the gateway also synchronizes the storage of data in the network (Step 6). When a
user accesses an IoT device through a gateway (Step 7 and Step 8), the gateway will
process user requests based on the saved user settings.
5</p>
      <p>Conclusions
1. The possibilities of using IoT objects as part of the SCDF are considered, which
will ensure a reduction in overhead costs for supporting the functioning of such a
chain.
2. It is shown that one of the main problems of applying IoT objects in the SCDF is to
ensure their level of protection from unauthorized access.
3. It is proposed to use Blockchain technology in the form of a set of software
platforms (TeleHash, BitTorrent and Ethereum) for enhancing the identification and
authentication of IoT objects as part of the SCDF.
4. The central result of the research is the developed algorithm for identifying IoT
objects within the SCDF and their authentication procedures, followed by
authorization of the user to provide him with access rights to resources. The scientific
novelty of the result lies in the complex using radio frequency identification
technologies, BLE and Blockchain, as the basic processing and maintenance architecture
for data to resolve conflicts in the field of confidentiality, that may occur during
the operation of the SCDF.
5. In the future, the intellectualization of objects of the Internet of things is supposed
by presenting them in the form of intelligent agents as part of the SCDF.</p>
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