CompTIA Network+ Exam Guide

1. Networking Fundamentals

Networking Models:

- OSI Model: A seven-layer model that helps understand how network protocols interact (Physical, Data Link, Network, Transport, Session, Presentation, Application).
- TCP/IP Model: A four-layer model commonly used in practical networking (Network Interface, Internet, Transport, Application).

Networking Devices:

- Router: Directs traffic between networks.
- Switch: Connects devices within a network and forwards data based on MAC addresses.
- Access Point (AP): Provides wireless connectivity within a network.

IP Addressing:

- IPv4 and IPv6 addressing schemes.
- Subnetting: Breaking a network into smaller, manageable pieces.
- Public vs. Private IP addresses, NAT (Network Address Translation).

Common Protocols:

- TCP (Transmission Control Protocol): Ensures reliable communication.
- UDP (User Datagram Protocol): Fast but less reliable communication.
- DNS (Domain Name System): Translates domain names into IP addresses.
- DHCP (Dynamic Host Configuration Protocol): Automatically assigns IP addresses to devices.

2. Network Implementations

Networking Topologies:

- Bus, Star, Mesh, and Hybrid topologies.
- Wired (Ethernet) vs. Wireless topologies.

Network Types:

- LAN (Local Area Network): Small network, typically within a single location.
- WAN (Wide Area Network): Larger network that spans geographical locations.
- VLANs (Virtual LANs): Allow segmentation of a network into smaller, isolated parts.

Networking Devices:

- Routers, switches, firewalls, load balancers, and proxy servers.
- Wireless access points and their configuration (SSID, security protocols).

Wireless Networking:

- Wi-Fi standards (802.11a/b/g/n/ac/ax).
- Wireless security (WPA2, WPA3).
- Frequency bands (2.4 GHz vs. 5 GHz).

Cabling:

- Copper (e.g., Cat5e, Cat6) vs. Fiber (e.g., single-mode, multi-mode).
- Connectors (RJ45, SC, LC).
- Signal interference and cable management best practices.

3. Network Operations

Monitoring and Management:

- SNMP (Simple Network Management Protocol): Used for monitoring network devices.
- Syslog: Centralized logging of events from network devices.
- NMS (Network Management Systems): Tools used to monitor and manage large networks.

Network Documentation:

- Importance of keeping accurate network diagrams, configuration documentation, and performance logs.

Performance Metrics:

- Latency, bandwidth, throughput, and jitter.
- Understanding QoS (Quality of Service) to prioritize critical traffic.

Network Policies:

- Role of SLAs (Service Level Agreements) in setting uptime and performance expectations.
- Incident response and change management processes.

4. Network Security

Device Security:

- Firewalls: Filter incoming and outgoing traffic.
- Intrusion Detection Systems (IDS) and Intrusion Prevention Systems (IPS).
- VPNs (Virtual Private Networks): Secure connections over the internet.

Authentication and Access Control:

- AAA (Authentication, Authorization, Accounting) frameworks.
- Multifactor authentication (MFA) and RADIUS/TACACS+ protocols.
- Role-based access control (RBAC).

Encryption:

- Symmetric vs. asymmetric encryption.
- Encryption protocols such as SSL/TLS, IPSec.
- Wi-Fi security (WPA2, WPA3).

Common Threats:

- Malware, DDoS attacks, phishing, and man-in-the-middle attacks.
- Mitigation strategies: firewalls, antivirus, patch management.

5. Network Troubleshooting

Troubleshooting Methodologies:

- Identify the problem, establish a theory, test the theory, establish a plan, implement the solution, verify functionality, and document the process.

Common Networking Problems:

- IP addressing issues (e.g., duplicate IP addresses, subnetting errors).
- Hardware failures (e.g., faulty cables, NICs, switches).
- Wireless interference or weak signal strength.
- DNS resolution issues.

Troubleshooting Tools:

- Ping, traceroute, nslookup, and ipconfig/ifconfig.
- Packet sniffers like Wireshark.
- Network analyzers to check traffic flow and detect bottlenecks.

Dictionary of Common Networking Terms