In this lesson,
we're going to cover the common documentation
that you are going to use in your enterprise networks.
This includes physical network diagrams,
logical network diagrams, wiring diagrams,
site survey reports, audit and assessment reports,
and baseline configurations.
First, we have physical network diagrams.
A physical network diagram
is used to show the actual physical arrangement
of the components that make up your network,
including the cabling and the hardware.
Typically, these diagrams give you a bird's-eye view
of a network in its physical space.
And it looks a lot like a floor plan,
but you may also see physical network diagrams
that show how things are going to be cabled
within an individual rack of a data center as well.
For example, if I have a physical network diagram
showing the floor plan of a small office,
I can notate on that floor plan
exactly where each IP-based CCTV is going to be installed.
Now, in this example,
you can see I have nine IP-based cameras
and how the cabling is going to run back to a central point,
such as this network video recorder
that contains nine power over ethernet ports
to run this camera system.
I could just as easily have another floor plan like this,
showing where all my network jacks
are going to be located in an office
and how the cables are being run back to a patch panel,
and from that patch panel back to an edge switch
that connects to all these devices.
Inside my data center, though,
I'm usually more concerned
with how things are physically located
within one single rack,
and so I can create a rack diagram.
For example, here's a diagram showing a rack
containing two storage area network controllers,
two firewalls, two switches,
three virtual machine host servers running ESXi,
a backup server, a module smart array,
and a tape backup library.
From this diagram,
you can clearly see where in this rack
each of those units is going to be located
and which network cables will connect to which ports
on which devices.
Another version of this type of diagram
may include a front view,
which also shows the location inside the cabinet,
and it can have the different device names
and the IP addresses for each of those devices,
but it won't show the actual network cables
and where they connect
because you're looking at the front of those devices.
Now, another type of physical network diagram we have
is used to provide documentation
for how our main distribution frame, or MDF,
and our intermediate distribution frame, or IDFs,
are connected and cabled.
In this example, you could see a very generic MDF
and IDF layout for a typical three-story office building.
Here, we have the MDF
on the bottom right corner of the first floor,
and then a smaller IDF on the right corner
of each of the remaining floors.
There's an interconnection between each IDF and the MDF,
and each floor has a single network cable
running to a jack into an office.
Now, this, of course, is a very oversimplified diagram,
or an overview diagram.
We can also have additionally detailed diagrams
depending on how much work we want.
That could show each rack inside the MDF or the IDF
and what they would look like, how they're cabled,
including their edge switches, patch panels,
and other networking equipment.
The second type of documentation we need to cover
is logical network diagrams.
Unlike the physical network diagrams
that show exactly which port a cable
is going to be connected to
and how it's ran on the physical floor plan
or the rack layout,
when we use a logical diagram,
we're going to use this to illustrate the flow of data
across a network,
and it's going to be used to show how devices
are communicating with each other.
These logical diagrams will include things like the subnets,
the network objects and devices,
the routing protocols and domains, voice gateways,
traffic flow, and network segments within a given network.
Traditionally, network diagrams were drawn by hand
and using symbols
to represent the different network devices,
like routers, switches, firewalls,
intrusion detection systems, and clients.
In this example, I'm using the standard Cisco notation
to demonstrate how the various switches and routers
are being connected to form this network.
On the logical diagram,
we also include the IP addresses
and the interface identifiers,
such as g0/1, or gigabitethernet 0/1,
or ATM1/0, which is for an ATM interface
for our routers and switches.
Notice the routers are being represented by a circle
with four arrows:
two pointing inward and two pointing outward.
Switches are going to be represented
by a square with four arrows all pointing outward.
Servers like a DHCP, DNS, or TFTP server
are represented by a large rectangle server icon,
and the computers are going to be shown using a computer icon.
Another symbol you may see included
is an intrusion detection system
or intrusion prevention system,
which is going to be a rectangle
that contains a circle inside of it
with two arrows crossing over the circle.
A firewall is usually represented by a brick wall,
and an access point is going to be represented by a rectangle
with a series of radio waves going out of it
from the left to the right.
Now, as you look at various network diagrams
on the internet,
you may come across some more modern network diagrams
that remove the symbols,
and instead use pictures of networking equipment
that's going to be used in the diagrams instead.
In this example,
you can see the router connected to the switches,
and those switches are connected to the client PCs.
Next, we have a wiring diagram,
and this is something we already looked at briefly
as part of our physical network diagrams.
Wiring diagrams can occur with both physical
and logical network diagrams,
as long as they're clearly labeled
which cable is connected to which port.
The more in-depth wiring diagrams
are going to include a floor plan or a rack diagram,
so you can see exactly where the cables are being run
in the physical environment.
Next, we have site survey reports.
These are often conducted
as part of a wireless survey or an assessment.
Now, a wireless site survey,
sometimes called an RF or radio frequency site survey,
or a wireless survey,
is the process of planning and designing a wireless network
to provide a wireless solution
that will deliver the required wireless coverage,
data rates, network capacity, roaming capability,
and quality of service, or QoS.
In this example, you can see a floor plan
that includes the locations
of each wireless access point being shown.
Then, rating out from each access point,
you see bands of color going from green,
to yellow, to orange, to red,
and this indicates the strength of the wireless signal.
Now, when you see green, that's a strong signal.
When you see red, that's a weaker signal.
Wired site surveys are also conducted sometimes,
but in these cases,
it's usually done as part of a preparation
for a major upgrade or installation.
With a wired site survey,
the installation team is going to come out
and look at your MDFs, your IDFs, and your data centers
to determine if you have the right power, space, and cooling
to support whatever new equipment you're going to be installing
as part of that upgrade.
For example,
if I was going to install three new racks of equipment
in your data center,
I need to go out there and look at it
and make sure you have the physical space required
to hold those three racks.
In addition to that,
I need to make sure you have a powerful enough HVAC system
to remove all the extra heat
that my new equipment in these three racks is going to produce.
I also want to make sure your site has the right power,
and backup generators, and battery backups
that you can handle all the extra power
that's going to be drawn by all this new equipment.
Next, we have audit and assessment reports.
Audit and assessment reports
are delivered to your organization
after a formal assessment has been conducted.
These reports will contain an executive summary,
an overview of the assessment scope and objectives,
the assumptions and limitations of the assessment,
the methods and tools used during the assessment,
a diagram showing the current environment and systems,
the security requirements,
a summary of findings and recommendations,
and the results of the audit.
Essentially, this report is going to contain
all the issues the audit team found with your organization,
as well as anything your organization is already doing right
and things they should continue to keep doing.
Finally, we have baseline configurations.
The documented baseline configurations
are the most stable versions of a device's configurations.
These baseline configurations
are a documented set of specifications
for an information system
or a configuration item within that system
that has been formally reviewed
and agreed on at a given point in time,
and which can now only be changed
through change control procedures.
So, if you want to change the baseline
due to an operational need,
you need to follow
the proper configuration management procedures
to request those changes.
Those changes will then be properly tested and approved,
and they become part of the new baseline
for those devices moving forward.
As you can see,
there is a bunch of documentation that you are going to use
in your enterprise networks,
including your physical network diagrams,
logical network diagrams, wiring diagrams,
site survey reports, audit and assessment reports,
and baseline configurations.