COMPLETE Secure Company Network System Design Using Packet Tracer - PART 1 & 2 | Network System

Introduction

This tutorial provides a comprehensive guide on designing and implementing a secure company network system using Cisco Packet Tracer. It covers various technologies and tools essential for creating a robust network infrastructure. This guide will help you understand the fundamental components such as firewalls, access points, routing, and network security, making it highly relevant for network engineers and IT professionals.

Step 1: Setting Up the Network Architecture

1. Define Network Zones

   • Identify the different zones: Inside, Outside, and DMZ.
   • Allocate IP address ranges for each zone.

2. Implement VLANs

   • Create VLANs for Corporate, Employees, External Auditors, and Guest Wi-Fi.
   • Use the following command to create VLANs on a Cisco switch:

     vlan [VLAN_ID]
     name [VLAN_NAME]
     

3. Configure Inter-VLAN Routing

   • Utilize Router-on-a-Stick configuration for routing between VLANs.
   • Ensure Virtual Interfaces (SVI) are configured properly on the router.

Step 2: Firewall Configuration

1. Deploy Cisco ASA Firewall

   • Integrate the Cisco ASA firewall in the network.
   • Set up inspection policies and Access Control Lists (ACLs) for traffic management.

2. Configure NAT

   • Implement Network Address Translation (NAT) for internal IPs to communicate with the external network.
   • Use the following NAT command:

     object network [OBJECT_NAME]
     nat (inside,outside) static [EXTERNAL_IP]
     

Step 3: Wireless Network Setup

1. Install Wireless LAN Controller

   • Add the Cisco Wireless LAN Controller to manage access points.
   • Configure lightweight access points to connect to the controller.

2. Security Settings for Wi-Fi

   • Set up WPA2 or WPA3 for secure wireless connections.
   • Define SSIDs for different user groups (Corporate, Guest, etc.).

Step 4: Implement High Availability

1. Configure HSRP for Redundancy

   • Set up Hot Standby Router Protocol (HSRP) for gateway redundancy.
   • Use commands like the following to configure HSRP on routers:

     standby [GROUP_NUM] ip [VIRTUAL_IP]
     standby [GROUP_NUM] priority [PRIORITY_VALUE]
     standby [GROUP_NUM] preempt
     

2. Utilize LACP for Link Aggregation

   • Implement Link Aggregation Control Protocol (LACP) to bundle multiple physical links.
   • Use the following command for configuration:

     interface Port-channel[NUMBER]
     switchport mode trunk
     

Step 5: Device and Service Configuration

1. Set Up Active Directory as DHCP Server

   • Configure Active Directory to handle DHCP requests for the network.
   • Ensure scopes are properly defined for each VLAN.

2. Configure Telephony Services

   • Integrate Cisco Voice Gateways for IP Telephony.
   • Set up IP Phones to connect to the telephony network.

Step 6: Security Measures

1. Implement SSH for Remote Access

   • Enable SSH on network devices for secure remote management.
   • Use the following command to configure SSH:

     ip domain-name [DOMAIN_NAME]
     crypto key generate rsa
     line vty 0 4
     transport input ssh
     

2. Apply Security Policies

   • Utilize Standard ACLs to restrict access to sensitive areas of the network.
   • Regularly review and update security policies to adapt to new threats.

Conclusion

Designing a secure company network involves multiple components and technologies, including firewalls, routing protocols, and wireless configurations. By following the steps outlined in this tutorial, you can create a robust and secure network environment. Next steps may include testing the network for vulnerabilities and implementing additional monitoring tools to ensure ongoing security.