Network+ (N10-009) Objective 3.0: Network Operations
SNMP
Simple Network Management Protocol
A protocol for collecting and organizing information about managed devices on IP networks and for modifying that information to change device behavior.
Key Features: Polling, Traps, MIBs, Get/Set operations
NetFlow
Network Flow Analysis
A network protocol for collecting IP traffic information and monitoring network flow, providing data about who, what, when, and where network traffic is flowing.
Key Features: Bandwidth monitoring, Application identification, Flow analysis
Syslog
System Logging Protocol
A standard for message logging that allows separation of the software that generates messages, the system that stores them, and the software that reports and analyzes them.
Key Features: Centralized logging, Severity levels, Message categorization
RMON
Remote Network Monitoring
A standard monitoring specification that enables various network monitors and console systems to exchange network-monitoring data.
Key Features: Traffic analysis, History collection, Alarm thresholds
IDS/IPS
Intrusion Detection/Prevention Systems
Systems that monitor network traffic for suspicious activity and issue alerts (IDS) or take action to prevent the activity (IPS) when detected.
Key Features: Signature detection, Anomaly detection, Real-time monitoring
Performance Monitoring
Resource Utilization Tracking
Tools that monitor network device performance metrics such as CPU usage, memory utilization, and interface statistics.
Key Features: Resource tracking, Threshold alerts, Trend analysis
A network baseline documents the normal operation of a network, providing a reference point for identifying abnormal behavior. It should include:
Baseline Components
- Normal traffic patterns and volumes
- Typical bandwidth utilization
- Expected latency and jitter measurements
- Standard error rates on interfaces
- Regular CPU and memory usage
- Common application response times
Baseline Best Practices
- Collect data over an extended period (2-4 weeks minimum)
- Include peak usage periods and different business cycles
- Regularly update baselines as the network evolves
- Document both averages and maximum/minimum values
- Use automated tools for consistent measurements
Using Baselines for Troubleshooting
When troubleshooting network issues, compare current performance metrics against established baselines to identify deviations. This helps to:
- Quickly identify abnormal behavior
- Determine the severity of an issue
- Focus troubleshooting efforts on the most significant changes
- Validate that implemented solutions have restored normal operation