Module Review

In this final module, we focused on the metrics and tools that define a healthy network:

  1. Latency & Jitter: Understanding the different types of delay and how variation in arrival times impacts real-time traffic like Voice and Video.
  2. Throughput Optimization: Maximizing the “pipe” using Window Scaling, MTU optimization, and understanding the Bandwidth-Delay Product (BDP).
  3. QoS Mechanisms: Prioritizing traffic using Classification, Marking (DSCP), and Queuing strategies to ensure critical services remain reliable during congestion.
  4. Network Monitoring: Gaining visibility using SNMP (Polling/Traps), NetFlow (Traffic analysis), and Syslog.
  5. Troubleshooting: Practical diagnosis using CLI tools like ping, traceroute, dig, and tcpdump.

1. Flash Quiz

1. What is Jitter?

  • Jitter is the variation in the delay (latency) of received packets. High jitter makes real-time applications choppy.

2. Which TCP feature is necessary to “fill the pipe” on high-speed, long-distance links with high latency?

  • TCP Window Scaling.

3. What is the difference between Traffic Policing and Traffic Shaping?

  • Traffic Policing drops traffic that exceeds a certain rate, while Traffic Shaping buffers (delays) traffic to smooth out bursts.

4. What does the traceroute command show you?

  • Every hop (router) that a packet takes on its path to a destination, and the latency at each hop.

5. Why is establishing a “Baseline” important for network monitoring?

  • Because without knowing what “Normal” looks like, you cannot identify when current traffic patterns or resource usage are abnormal or indicative of a failure.

2. Course Completed!

Congratulations! You have successfully traversed the entire Computer Networks curriculum. You now understand how data travels from a single bit on a wire, across local segments, through global routers, and up to the applications that power the modern world.