Page 59 - ITUJournal Future and evolving technologies Volume 2 (2021), Issue 1

ITU Journal on Future and Evolving Technologies, Volume 2 (2021), Issue 1

in which the sender distributes a one‑time‑key to the in‑ Integration of IoTs with PCNs. Use of IoT devices for
termediary nodes. Although the HTLC mechanism is im‑ payments are inevitable. Aside from the fact that most
proved for the security of the users the sender’s privacy IoT devices are not powerful to run a full node, the secu‑
is not protected; each of the intermediaries learns the rity and privacy of the payments and the device identities
sender. However, relationship anonymity can still be sat‑ within the IoT ecosystem need to be studied. These de‑
is ied. vices are anticipated to be able to participate in the net‑
work through gateways. The revelation of device owner‑
5. FUTURE RESEARCH ISSUES IN PCNS ship will reveal the real identity of the users to the public
which is a big threat to privacy.
Privacy in PCNs is an understudied topic and many open
issuesneedtobeaddressedasfutureresearch. Inthissec‑ Privacy in Permissioned PCNs. While establishing a
tion, we summarize these issues: network of merchants in permissioned PCNs, the mer‑
chants should at least disclose their expected trade vol‑
Abuse of the PCN protocols. Most of the PCNs rely umeinordertoestablishadependablenetwork. Thiswill,
on public cryptocurrencies, whose protocol implementa‑ however, yield trade secrets of the merchants. To prevent
tions are public. This freedom can be abused such that by this, zero‑knowledge proof based multi‑party communi‑
changing some parameters and algorithms in the design, cation can be explored.
an attacker can behave differently than what is expected.
This will bring privacy leakages and censorship to the net‑ 6. CONCLUSION
work. A topological reordering of the network will help
solve this problem. If a sender gets suspicious about an PCN is a promising solution to make cryptocurrency‑
intermediary node, it can look for alternatives instead of based payments scalable. This idea aimed to ix two ma‑
using that node. jor shortcomings of cryptocurrencies: long con irmation
PCN topologies. The most widely accepted and readily times and high transaction fees. There are many studies
available solution, Lightning Network, has a user base of on the design of payment channels and PCNs to make the
more than 12 thousand nodes as of today. Furthermore, transfers secure and ef icient. However, these studies do
if the channels are observed it creates an impression that not mention the possible privacy leakages of these meth‑
most of the nodes are experimental to discover the capa‑ ods in case of a wide adaptation of proposed ideas. In this
bilities of LN. Even the trust in the protocol becomes per‑ paper, we irst made the categorization of PCNs based on
fect, assuming that ordinary users will put hundreds of the type of blockchain being used and the topological be‑
dollars in their channels as collateral does not make per‑ havior of the network. After clearly de ining possible pri‑
fect sense. This reality reminds us that PCNs are inclined vacy leakages in a PCN, we compared and contrasted the
to slide towards centrally managed networks. In that state‑of‑the‑art PCN approaches from the privacy point of
case, topology formation comes into the scene. Right now, view.
the autopilot feature of lnd (an LN client) highlights
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© International Telecommunication Union, 2021 43