Network Segmentation VLANS and Subnets

Network Segmentation:
VLANS and Subnets

Network Security: Domain 3 Lesson 3 Part1

Let's start by reveiving Binary

Are you ready?

On the next few slides, you will be asked to convert a decimal (regular base-10 number into binary (Base-2) notation. You will only have 30 seconds to do your conversion so to a moment to write out your place-value chart if you need.

Fill in the Blanks

Fill in the Blanks

Fill in the Blanks

Multiple Choice

What is a network confined to a single location called?

• WAN

• MAN

• LAN

• PAN

• PAN

• Usually Hardware based but can be software based (i.e. Windows Server has routing capabilities)

• Usually OSI Layer 3 devices (Network Layer)

• Controls traffic between networks via routing tables of IP addresses

​Routers

• Connects traffic within a network via routing tables of MAC addresses

• Usually OSI Layer 2 devices

• There are some switches with Layer 3 capability

​Switches

Important Routing Devices

Routing is the process of path selection in any network.

​Switch

​Router

Multiple Choice

Routers can be hardware or software based.

• True

• False

Multiple Choice

Switches are able to effectively connect devices within a network and allow them to communicate by making ____________ tables.

• Encryption

• IP address
• MAC address
• Subnet mask

Multiple Choice

Switches usually operate on what OSI layer?

• Layer 2

  Data Link

• Layer 3

  Network

• Layer 5

  Session

• Layer 7

  Application

• Layer 1

  Physical

Multiple Choice

What is usually referred to as a Layer 3 device?

• Hubs

• Switches

• Routers

• Bridges

Multiple Choice

Routers create routing tables made up of MAC addresses.

• True

• False

Why Do We Segment Networks

5 Reasons to Segment

1. Efficient Network Management

2. Improved Network Performance

3. Enhanced Security

4. Optimized IP Address Usage

5. Logical Grouping

VLAN = Virtual Local Area Network

A logical network managed on physical switches ​

• Used to segregate different groups of users on the same physical network usually using switches.

• Ports on the same switch can be assigned to different VLANs.

• For example, the Marketing department and the Accounting department can be part of the same LAN but each department can be assigned their own ports on a physical switch

• Devices in different VLANs cannot communicate directly. However, they can communicate through a router.

• In this example, we create two VLANs: VLAN-10 and VLAN-20 on the same physical switch.

• We assign port-1 to 4 to VLAN-10 and port-5 to 8 to VLAN-20.

• After this, ports 1, 2, 3, and 4 will share broadcast in VLAN-10, and ports 5, 6, 7, and 8 will share broadcast in VLAN-20.

• So VLANS divides and network into separate Broadcast Domains.

​VLAN

Multiple Choice

What is a VLAN?

• A router that has layer 4 capabilities.

• A theoretical network based on a coding concept

• A physical network created within a logical network

• A logical network created within a physical network

Multiple Choice

Routers are not needed to route traffic between VLANs.

• True

• False

Multiple Choice

VLANs segregate traffic by ...

• creating separate broadcast domains
• encrypting data packets
• increasing network speed
• combining multiple networks

An IPv4 address consists of 32 bits that are grouped in four octets and is written in dotted decimal format, where a dot separates each octet.
The address has a network portion and a host portion.

​IPv4 Review

Can I Segregate Networks based on IP addresses?

Subnetting

​Creating networks inside a network using IP addresses

• Subnets break large networks into smaller, more manageable networks that run more efficiently

• Each subnet allows its connected devices to communicate with each other.

• Routers are needed to communicate between subnetss.

• While VLANs use ports on a physical switch to create different broadcast domains to segregate users, subnets groups IP addresses to create logical networks within a network.

• In this example, the network consists of 256 addresses (37.1.1.0 thru 37.1.1.255)

• ​The network administrator uses subnetting to create 4 subnets of 64 addresses (one subnet for each office)

• 256 / 4 = 64

• The subnet mask will identify which part of an IP address belongs to the network and which part identifies a specific device on that network

• Subnet masks can be used to identify IP addresses on the same network.

​

​Subnetting

Activity (25 minutes)

​Subnet Masks Unmasked- Challenge

• Write your name and period on the worksheet handed out by Mr. Carr

• Complete worksheet

• Review your answers with your Group

Challenge Debrief

​Did you notice a pattern?

Let's see how well you understood subnets and subnet masks.

​Exit Ticket (5 Minutes)

Answer a few questions to see how well you understood today's lesson.

Multiple Choice

How are VLANs and Subnets alike?

• VLANs are only used for wireless networks, subnets are only used for wireless networks as well.

• Both VLANs and subnets are used to segment networks for improved performance and security.
• VLANs and subnets are alike because they both involve using dynamic solutions to bandwidth issues.

• Subnets can only be used in IPv6 networks, just like VLANS

Multiple Choice

An IP address of 172.168.0.101 and a subnet mask of 255.255.0.0 belongs to which of the following IPv4 classes?

• Class A
• Class E
• Class C
• Class B
• Class D

Multiple Choice

Which of the following best identifies Device A?

• Hub

• Router

• Switch

• Access Point

Multiple Choice

How are VLANS and Subnets different?

• VLANs operate at Layer 2 for network segmentation, while subnets operate at Layer 3 for IP address management.
• Subnets operate at Layer 2, while VLANs operate at Layer 3.
• VLANs are used for routing, while subnets are for switching on networks.

• VLANs and subnets are the same thing, there is no difference between the two.

Multiple Choice

Which of these is a valid Subnet Mask?

• 255.255.68.255

• 192.168.1.1
• 255.255.255.0

• 255.192.0.0

Open Ended

Are these two IP addresses on the same network? Why or why not?

Host 1 IP address: 94.255.192.54

Host 2 IP address: 94.255.49.140

Subnet mask: 255.255.0.0

Congratulations!

​You have completed this lesson!

We have just touched the surface on network segmentation. But you should have a better understanding VLANs and Subnets.