
Twenty networking topics you can play
Watch a video, try a simulation, then check the exam answers.
Pick a unit




















Search the exam answers
264 questions with answers across the topics. Type a word such as “window” or “header”.
What stands behind the demos
| CRC | Matches Python’s zlib CRC-32, and the textbook example 1101011011 divided by 10011 leaves 1110. |
|---|---|
| ALOHA and CSMA | A Monte Carlo run lands on 0.184 and 0.367, the textbook peaks. |
| Switches | A real learning switch runs over UDP on one laptop, with no root access. |
| Sliding window | 3,588 simulated runs: every set of up to three lost frames, windows 1 to 6. |
| Tunneling | A separate Python version builds byte-identical packets, and a saved capture decodes in Scapy. |
| IPv6 | 412 address cases match Python’s ipaddress module. The test laptop had no public IPv6 address, and the page says so. |
| Sockets | Every error name and number matches real sockets on this machine, over 6,022 checks including 3,000 random programs. |
| Ciphers | All three ciphers match an independent Python version, with round trips for every shift. |
| Firewalls | 23 checks: first match wins, order matters, and the alarm thresholds that work are exactly 4 to 10. |
| UDP vs TCP | 6,006 checks over 1,000 random lines. The right protocol passes at least 93% of runs. |
Checked by running tests and by headless-browser screenshots. These pages have not been reviewed by hand yet.