Cisco Switch & Router Core configuration, VLAN Segmentation & DHCP Inter-VLAN Routing Lab

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Project

Switch & Router Security, VLAN Management and DHCP Inter-VLAN Routing (Packet Tracer)

Objective

Designed and simulated a secure enterprise network in Cisco Packet Tracer, implementing VLAN segmentation, router-on-a-stick inter-VLAN routing, and centralized DHCP. Strengthened security, port security, and access controls practicing realworld network administration in a virtual lab.

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Skills Learned

• Cisco IOS CLI configuration
• Device hardening techniques
• VLAN creation and interface assignment
• Inter-VLAN routing via subinterfaces
• DHCP setup and relay forwarding
• Security banners, password encryption, and Telnet/SSH access

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Tools Used

Tool	Purpose
Cisco Packet Tracer	Network simulation
Cisco Switch	VLAN creation, trunking, hardening
Cisco Router	Inter-VLAN routing, hardening
DHCP Server	Dynamic IP address management
End Devices (PCs)	Test DHCP and routing

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Topology Overview

Ref: Topology

Lab Sections

1. Switch Hardening
2. Router Hardening
3. VLAN Setup
4. Router-on-a-Stick Inter-VLAN Routing
5. DHCP Server Configuration
6. DHCP Relay Configuration
7. Testing & Verification

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1. Switch Hardening (SWITCH01)

Step 1: Enter Privileged Mode

Switch> enable

Step 2: Configure Hostname

Switch# configure terminal
Switch(config)# hostname SWITCH01

Step 3: Configure MOTD Banner

SWITCH01(config)# banner motd #**
==========================================
Warning!! Authorized Users Only!!
==========================================#

Step 4: Set Console Password

SWITCH01(config)# line con 0
SWITCH01(config-line)# password Paramaribo
SWITCH01(config-line)# login

Step 5: Set VTY Line Password (Telnet)

SWITCH01(config)# line vty 0 15
SWITCH01(config-line)# password Wanica
SWITCH01(config-line)# login

Step 6: encrypt passwords

SWITCH01(config)# service password-encryption

Step 7: Secure Enable Mode

SWITCH01(config)# enable secret Suriname

Step 8: Configure Management Interface

SWITCH01(config)# interface vlan 1
SWITCH01(config-if)# ip address 192.168.50.100 255.255.255.0
SWITCH01(config-if)# no shutdown

Ref: SWITCH01

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2. Router Hardening (ROUTER1)

Step1: Set host name

Router> enable
Router# configure terminal
Router(config)# hostname ROUTER1

Step 2: Set Enable Secret

ROUTER1(config)# enable secret Paramaribo

Step 3: Encrypt Passwords

ROUTER1(config)# service password-encryption

Step 4: Configure MOTD Banner

ROUTER1(config)# banner motd #
============================
Unauthorized Access is Prohibited!
Verboden Toegang!
============================#

Step 5: Secure Console Access

ROUTER1(config)# line con 0
ROUTER1(config-line)# password Paramaribo
ROUTER1(config-line)# login

Step 6: Secure VTY Access (Telnet)

ROUTER1(config)# line vty 0 4
ROUTER1(config-line)# password Wanica
ROUTER1(config-line)# login

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3. VLAN Configuration (SWITCH01)

VLAN Creation & Assignment

Create VLANs

SWITCH01(config)# vlan 10
SWITCH01(config-vlan)# name Sales
SWITCH01(config)# vlan 20
SWITCH01(config-vlan)# name IT
SWITCH01(config)# vlan 30
SWITCH01(config-vlan)# name HR

Assign Ports

SWITCH01(config)# interface range fa0/2 - 5
SWITCH01(config-if-range)# switchport mode access
SWITCH01(config-if-range)# switchport access vlan 10

SWITCH01(config)# interface range fa0/6 - 10
SWITCH01(config-if-range)# switchport mode access
SWITCH01(config-if-range)# switchport access vlan 20

SWITCH01(config)# interface range fa0/11 - 15
SWITCH01(config-if-range)# switchport mode access
SWITCH01(config-if-range)# switchport access vlan 30

Ref:

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Configure Trunk Port (To ROUTER1)

SWITCH01(config)# interface fa0/20
SWITCH01(config-if)# switchport mode trunk

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4. Router-on-a-Stick: Inter-VLAN Routing

Configuration Subinterfaces on ROUTER1

VLAN 10

ROUTER1(config)# interface g0/0.10
ROUTER1(config-subif)# encapsulation dot1Q 10
ROUTER1(config-subif)# ip address 192.168.10.1 255.255.255.0

VLAN 20

ROUTER1(config)# interface g0/0.20
ROUTER1(config-subif)# encapsulation dot1Q 20
ROUTER1(config-subif)# ip address 192.168.20.1 255.255.255.0

VLAN 30

ROUTER1(config)# interface g0/0.30
ROUTER1(config-subif)# encapsulation dot1Q 30
ROUTER1(config-subif)# ip address 192.168.30.1 255.255.255.0

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5. DHCP Server Configuration

Ref:

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6. DHCP Relay (IP Helper)

Forward DHCP Requests in ROUTER1

VLAN 20

ROUTER1(config)# interface g0/0.20
ROUTER1(config-subif)# ip helper-address 192.168.10.5

VLAN 30

ROUTER1(config)# interface g0/0.30
ROUTER1(config-subif)# ip helper-address 192.168.10.5
#
**DHCP server is in vlan 10, No DHCP-relay needed for vlan10**

Tests DHCP

Ref: HR Lola-PC VLAN 30

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Ref: IT Victor-PC VLAN 20

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