In this lesson,
we're going to discuss network components.
Now, when it comes to networks, the whole purpose
is to get data from one place to another
and from one machine to another.
Whether that's carrying voice, video, or data,
it's going to have to get across the network somehow.
So what does our networks actually consist of?
Well, that's what we're going to answer in this lesson
as we begin to explore the different types
of network components that we utilize.
Things like clients, servers, hubs, switches,
wireless access points, routers,
firewalls, load balancers, proxies,
intrusion detection and intrusion prevention systems,
controllers, network-attached storage devices,
storage area networks, media, and WAN links.
Now, some of those terms probably look familiar
and others may not.
So we're going to go through each of those
very briefly in this lesson.
Now, first we have clients.
Clients are devices
that users are going to access the network with.
These are things like workstations, laptops, tablets,
smartphones, smart TVs, and even Wi-Fi enabled thermostats.
These can be any device
that is simply going to connect to the network,
and we refer to all of them collectively as our clients.
Second, we have servers.
Now, servers provide resources to the rest of your network,
and some common examples include things like email servers,
file servers, web servers, and many others.
These servers can exist on dedicated hardware devices,
or they can rely on some specialized software
that allows a device to act as a server
for other clients on the network.
Third, we have hubs.
Now, hubs are older technologies.
They're not commonly going to be used in our modern networks,
but they're still relevant for the exam
because they often are going to be used
as one of your answer choices.
Now, hubs are devices that connect other network devices
like clients and servers together over a local area network.
However, they do have some limitations,
such as increased network errors
due to their broadcasting nature of these devices.
Now, hubs were first developed a long time ago,
but over time they evolved into bridges
and then eventually into what we use today,
which are known as switches.
Now, switches are just, effectively,
a much smarter version of a hub
because our switches can learn
which devices are on which ports
and only forward traffic to those intended recipients.
Fourth, we have switches.
Now switches are really just smarter hubs
that provide us with more security
and more efficient bandwidth utilization.
Switches are used to connect network devices
and only forward traffic from one port
to the intended destination port,
and this helps to avoid unnecessary broadcasting
of your data over the network.
Fifth, we have wireless access points.
Now, wireless access points, also known as access points,
will allow wireless devices
to connect to your wired network.
These wireless access points, also known as WAPs,
or simply as APs, are very prevalent in our homes,
businesses, and large networks.
Just like hubs, access points are used to broadcast data,
but they do this over a radio frequency wave
instead of going over a copper or fiber cable.
Sixth, we have routers.
Now, routers are a crucial component in our modern networks
because they're used to connect different networks together.
These routers can make intelligent forwarding decisions
based on the IP addresses of the different clients, servers,
or other devices that are communicating over the network.
Modern routers are predominantly going to rely
on the internet protocol
to route the traffic across the network
using many different types of routing protocols.
Seventh, we have firewalls.
Now, firewalls serve as a security barrier
between your internal network and the external world,
which is typically going to be the internet.
These firewalls can monitor and control
incoming and outgoing network traffic
based upon predetermined security rules
by using access control lists.
Now, this is going to help protect your network
from unauthorized access, cyber attacks,
and other online threats.
These firewalls can be either hardware based,
software based, or a combination of both of these.
Eighth, we have load balancers.
Now, load balancers are devices or software
that are going to distribute network
or application traffic across multiple servers.
This increases the efficiency, capacity,
and reliability of the services
by ensuring that no single server
is going to bear too much of that demand.
By balancing our requested loads,
this is going to prevent any one server
from becoming a bottleneck,
and this will improve our overall network performance.
Ninth, we have a proxy.
Now, a proxy server's going to act as an intermediary
between a user's device and the internet.
This device called a proxy can provide functionalities like
web filtering, shared network connections,
and data caching to improve your overall performance.
Proxies can also be used to enhance security and privacy
by hiding the user's real IP address
and limiting their exposure to the internet.
Tenth, we have intrusion detection systems known as IDSs
and intrusion prevention systems known as IPSs.
Now, IDSs or intrusion detection systems
are designed to detect unauthorized access or anomalies
on your network and then alert the system administrator
of those anomalies.
Now, on the other hand, an IPS
or intrusion prevention system
will not only detect those threats like an IDS would,
but it can also take actions to prevent the intrusion,
like blocking that traffic from entering your network
or dropping any kind of harmful packets
that may be attempting to get into your network.
Eleventh, we have controllers.
Now controllers are particularly going to be used
in the context of software-defined networking or SDN.
These controllers are really central units
that are going to be used to manage the flow control
to those networking devices.
This enables network administrators to dictate the behavior
of the network switches and routers through software,
and this gives us more flexibility and efficiency.
Twelfth, we have network-attached storage or NAS devices.
Now, an N-A-S or NAS device
is a dedicated file storage system
that provides data access
to a heterogeneous group of clients.
Now, these things are going to be connected to a network
and they allow for the data storage and retrieval
from a centralized location
for authorized network users and all of those clients.
Thirteenth, we have storage area networks,
also known as a SAN.
Now, a SAN or S-A-N
is a high speed network that provides access
to consolidated block-level data storage.
SANs are designed to handle large volumes of data,
and they're typically used to enhance storage devices
such as disc arrays and tape libraries
and make them accessible to your servers.
Fourteenth, we have media.
Now in the world of networking,
media refers to the physical materials
that are used to transmit the data.
This can be something like a copper cable,
a fiber optic cable, or even wireless signals.
Each of these different media types
does have its own unique properties,
including its own strengths and limitations,
and this will influence its use
in different network scenarios that you may be designing.
Fifteenth and finally, we have WAN links.
Now, a WAN link or a wide area network link
is going to be used to connect networks
over large geographical areas,
such as between cities or countries.
WAN links are essential for global connectivity
and they enable data exchange over long distances
using technologies like lease lines,
satellite communications, or cellular networks.
So remember, understanding network components
is going to be crucial in the field of information technology.
From clients and servers to more complex elements
like firewalls, load balancers, and WAN links
each component does play a vital role
in ensuring the efficient and secure data transmission
of our information.
Knowledge of these components is not only going to aid you
in the design of your networks and its management,
but it also enhances your ability to conduct problem solving
and to implement security measures
in an increasingly interconnected world.
Later on as we go through this course,
we're going to talk more about each
and every one of these different devices, how they operate,
and what they're going to be used for in your network designs.