- [Instructor] The fog consists
of the OT, operational technology,
and IT, information technology networks.
Its main job is to move data from the sensors
to the backhaul that takes it up to the internet.
The OT network is operational specific.
It supports the product or the company's operations.
These networks have grown individually
to support the various industries in which they found.
Their job is to connect the sensors and the actuators.
However, they are usually proprietary.
These networks are generally in the product itself.
Now remember, the product can be a discrete product,
a system, or an environment.
Therefore, they can be a personal network,
a local network, or a wide area network.
From a hardware perspective, they consist of gateways.
This is negatively referred to as the internet of gateways.
There are hundreds of proprietary protocols
in the OT network.
Protocols for automation, industrial control,
building, power automation, automobiles, homes.
They're all different and all have been designed
specifically for their purpose.
The second half of the fog
is the information technology network or IT network.
Bridging the OT network and the IT network is the radio.
These radios can take the form of Bluetooth,
WiFi, cellular, LPWA, or others.
The connection between the IT and the OT networks
is generally wireless, but Ethernet can be used.
The IT network's job is to move the data
from the receiving radio to the backhaul up link
to the internet.
Let's consider our IoT drier.
Data from the sensors
are carried across the internal network.
This is the OT network.
They are then transmitted over the air using WiFi.
The IT network is a small network in your home
between your router and eventually the fiber up link
that leads it to the internet.
Hardware in the IT network using the internet of things
is the same as the hardware used in the internet of people.
Routers, switches, firewalls, the technology is the same
because the network is the same.
The IT network has been standardized on IP.
That is Internet Protocol.
This is a major benefit over the OT network.
It is a benefit in terms of cost, implementation,
but also this provides an attack vector.
The problem is the scene between the OT network
and the IT network needs to be translated by a gateway.
This gateway is a favorite source of attacks.
Overtime, we will unify the fog with one protocol.
That will be the IP protocol.
The IT network is getting closer to the data source
and will eventually replace the OT network protocols.
The trend in the internet of things
is to move computing closer to the data source.
This will lead to first, gateway computing in the OT network
and then mist computing on the embedded system.
The fog connects the proprietary protocols of the OT network
to the IT network that standardize on Internet Protocol, IP.
Overtime, IP will extend all the way to the end node,
thereby eliminating the proprietary OT protocols
of the past.