About Me
Cisco Certified Network Associate (CCNA) - Security
1 Network Security and Secure Connectivity
1-1 Introduction to Network Security
1-1 1 Definition and Importance of Network Security
1-1 2 Threats and Vulnerabilities in Networks
1-1 3 Security Policies and Compliance
1-2 Secure Network Design
1-2 1 Network Segmentation and Zoning
1-2 2 Secure Network Topologies
1-2 3 Designing Secure Network Architectures
1-3 Secure Connectivity
1-3 1 VPN Technologies (IPsec, SSLTLS, GRE)
1-3 2 Remote Access Security
1-3 3 Site-to-Site and Remote Access VPNs
2 Secure Access
2-1 AAA (Authentication, Authorization, and Accounting)
2-1 1 AAA Protocols (RADIUS, TACACS+)
2-1 2 Implementing AAA in Network Devices
2-1 3 Role-Based Access Control (RBAC)
2-2 Identity Management
2-2 1 User Authentication Methods (Passwords, Tokens, Biometrics)
2-2 2 Single Sign-On (SSO) and Federated Identity
2-2 3 Identity Federation and Directory Services
2-3 Access Control Lists (ACLs)
2-3 1 Standard and Extended ACLs
2-3 2 Applying ACLs to Network Devices
2-3 3 ACL Best Practices and Troubleshooting
3 Secure Routing and Switching
3-1 Secure Routing Protocols
3-1 1 OSPF and EIGRP Security
3-1 2 BGP Security (MD5, TCP MD5 Signature Option)
3-1 3 Secure Routing Protocol Configuration
3-2 Secure Switching
3-2 1 Switch Security Features (Port Security, DHCP Snooping)
3-2 2 Implementing Secure VLANs
3-2 3 Switch Security Best Practices
3-3 Network Address Translation (NAT) Security
3-3 1 NAT Types and Security Considerations
3-3 2 Configuring Secure NAT on Routers
3-3 3 NAT and Firewall Integration
4 Secure Wireless Networks
4-1 Wireless Security Protocols
4-1 1 WPA2 and WPA3 Security
4-1 2 RADIUS Integration with Wireless Networks
4-1 3 Wireless Encryption (TKIP, CCMP)
4-2 Secure Wireless Deployment
4-2 1 Wireless Network Design Considerations
4-2 2 Implementing Secure Wireless Access Points
4-2 3 Wireless Intrusion Detection and Prevention Systems (WIDSWIPS)
4-3 Wireless Threats and Mitigation
4-3 1 Common Wireless Attacks (Rogue AP, Evil Twin)
4-3 2 Mitigating Wireless Threats
4-3 3 Wireless Security Best Practices
5 Network Threat Defense
5-1 Intrusion Detection and Prevention Systems (IDSIPS)
5-1 1 IDSIPS Technologies and Architectures
5-1 2 Signature-Based and Anomaly-Based Detection
5-1 3 Implementing and Managing IDSIPS
5-2 Firewalls and Network Security
5-2 1 Firewall Types (Stateful, Stateless, Next-Generation)
5-2 2 Firewall Policies and Rules
5-2 3 Configuring and Managing Firewalls
5-3 Network Access Control (NAC)
5-3 1 NAC Architectures and Protocols
5-3 2 Implementing NAC Solutions
5-3 3 NAC Best Practices and Troubleshooting
6 Secure Network Management and Monitoring
6-1 Network Management Protocols
6-1 1 SNMP Security (v1, v2c, v3)
6-1 2 Secure Network Management Practices
6-1 3 Implementing Secure SNMP
6-2 Network Monitoring and Logging
6-2 1 Network Monitoring Tools and Techniques
6-2 2 Log Management and Analysis
6-2 3 Monitoring and Logging Best Practices
6-3 Network Device Hardening
6-3 1 Device Hardening Techniques
6-3 2 Secure Device Configuration
6-3 3 Device Hardening Best Practices
7 Cryptography and VPNs
7-1 Cryptographic Concepts
7-1 1 Symmetric and Asymmetric Encryption
7-1 2 Hashing and Digital Signatures
7-1 3 Public Key Infrastructure (PKI)
7-2 VPN Technologies
7-2 1 IPsec VPN Architecture
7-2 2 SSLTLS VPNs
7-2 3 VPN Deployment and Management
7-3 Secure Communication Protocols
7-3 1 Secure Email (SMIME, PGP)
7-3 2 Secure Web Protocols (HTTPS, SSLTLS)
7-3 3 Secure Communication Best Practices
8 Security Incident Response and Management
8-1 Incident Response Planning
8-1 1 Incident Response Process (IRP)
8-1 2 Incident Handling and Containment
8-1 3 Incident Response Best Practices
8-2 Forensics and Evidence Collection
8-2 1 Network Forensics Techniques
8-2 2 Evidence Collection and Preservation
8-2 3 Forensics Best Practices
8-3 Disaster Recovery and Business Continuity
8-3 1 Disaster Recovery Planning (DRP)
8-3 2 Business Continuity Planning (BCP)
8-3 3 Disaster Recovery and BCP Best Practices
3.2 Secure Switching

3.2 Secure Switching

Key Concepts

Port Security

Port Security is a feature that allows a switch to restrict the number of MAC addresses that can be learned on a specific port. This prevents unauthorized devices from connecting to the network and helps mitigate MAC address spoofing attacks.

Example: A switch port is configured to allow only two MAC addresses. If a third device attempts to connect, the port can be set to shut down, place the port in an error-disabled state, or take other specified actions.

Analogies: Think of port security as a bouncer at a club who only allows a limited number of people with specific IDs to enter. If someone without the correct ID tries to get in, the bouncer can take action to prevent entry.

Dynamic ARP Inspection (DAI)

Dynamic ARP Inspection (DAI) is a security feature that protects against ARP spoofing attacks by validating ARP packets in the network. DAI uses DHCP snooping bindings to check the validity of ARP requests and responses.

Example: A switch with DAI enabled will drop ARP packets that do not match the DHCP snooping bindings. This prevents attackers from sending fake ARP messages to redirect traffic to their devices.

Analogies: Consider DAI as a security guard who checks the IDs of people entering a building. If someone tries to enter with a fake ID, the guard will stop them from entering.

DHCP Snooping

DHCP Snooping is a security feature that protects against rogue DHCP servers by filtering and logging DHCP messages. It creates a trusted and untrusted port configuration, allowing only trusted DHCP servers to provide IP addresses.

Example: A switch with DHCP snooping enabled will only accept DHCP offers from trusted ports. If a rogue DHCP server tries to provide IP addresses on an untrusted port, the switch will ignore its offers.

Analogies: Think of DHCP snooping as a receptionist who only accepts business cards from verified companies. If an unknown company tries to hand out business cards, the receptionist will refuse them.

Storm Control

Storm Control is a feature that prevents network outages caused by excessive broadcast, multicast, or unknown unicast traffic. It monitors traffic levels and can take action, such as dropping or rate-limiting packets, when thresholds are exceeded.

Example: A switch with storm control enabled can be configured to drop broadcast traffic if it exceeds 10% of the total bandwidth. This prevents broadcast storms from overwhelming the network.

Analogies: Consider storm control as a traffic cop who regulates the flow of cars on a busy road. If too many cars try to enter the road, the cop can limit the number of cars to prevent congestion.

Private VLANs

Private VLANs (PVLANs) are a network segmentation technique that isolates traffic between different VLANs on the same physical switch. PVLANs can be used to enhance security by preventing communication between devices on different segments.

Example: A switch with PVLANs configured can isolate guest devices from corporate devices. This ensures that guest devices cannot communicate with corporate devices, enhancing security.

Analogies: Think of PVLANs as separate conference rooms within a building. Each room has its own set of attendees, and attendees from one room cannot communicate with attendees from another room unless explicitly allowed.

Conclusion

Understanding Secure Switching is crucial for maintaining a secure and efficient network. By implementing features such as Port Security, Dynamic ARP Inspection, DHCP Snooping, Storm Control, and Private VLANs, network administrators can protect their networks from unauthorized access and malicious activities.

© 2024 Ahmed Baheeg Khorshid. All rights reserved.