Blockchain Security, the solution to IoT?

Hello everyone.
I was asked a question if crypto-currency or blockchain security is the best to IoT. Here is what i have to give...

First of all, i'd like to clear the air; the fundamental difference
between these concepts has to do with how distributed
ledger technology is used.

The Internet of Things (IoT) is experiencing exponential growth in research and industry, but it still suffers from privacy and security vulnerabilities. Conventional security and privacy approaches tend to be inapplicable for IoT, mainly due to its decentralized topology and the resource-constraints of the majority of its devices. BlockChain (BC) that underpin the crypto- currency Bitcoin have been recently used to provide security and privacy in peer-to-peer networks with similar topologies to IoT. However, BCs are computationally expensive and involve high bandwidth overhead and delays, which are not suitable for IoT devices. This position paper proposes a new secure, private, and lightweight architecture for IoT, based on BC technology that eliminates the overhead of BC while maintaining most of its security and privacy benefits. The described method is investigated on a smart home application as a representative case study for broader IoT applications. The world today uses different types of BC’s depending on where in the network hierarchy a transaction occurs, and uses distributed trust methods to ensure a decentralized topology

What is Blockchain?
Blockchain is a database that maintains a
continuously growing set of data records. It is
distributed in nature, meaning that there is no
master computer holding the entire chain. Rather,
the participating nodes have a copy of the chain.
It’s also ever-growing — data records are only
added to the chain.
A blockchain consists of two types of elements:
Transactions are the actions created by the
participants in the system.
Blocks record these transactions and make
sure they are in the correct sequence and
have not been tampered with. Blocks also
record a time stamp when the transactions
were added.

What are Some Advantages of
Blockchain?
The big advantage of blockchain is that it’s
public . Everyone participating can see the blocks
and the transactions stored in them. This doesn’t
mean everyone can see the actual content of your
transaction, however; that’s protected by your
private key.
A blockchain is decentralized, so there is no
single authority that can approve the transactions
or set specific rules to have transactions
accepted. That means there’s a huge amount of
trust involved since all the participants in the
network have to reach a consensus to accept
transactions.

Two Main Types of Blockchain
In a public blockchain, everyone can read or
write data. Some public blockchains limit the
access to just reading or writing. Bitcoin, for
example, uses an approach where anyone
can write.
In a private blockchain, all the participants
are known and trusted. This is useful when
the blockchain is used between companies
that belong to the same legal mother entity.

Blockchain holds the potential to securely unlock
the business and operational value of Internet of
Things (IoT) to support common tasks, such as
sensing, processing, storing information, and
communicating. The Blockchain enables
business partners to access and supply IoT data
without the need for central control and management.
All business partners can verify each transaction,
preventing disputes and ensuring each partner is held
accountable for their individual roles in the overall
transaction.