15-441/641 — Computer Networks

Course website for Fall 2026. The site is intentionally plain HTML/CSS: GitHub Pages can publish it without a package manager or a generated directory.

Preview locally

Create the ignored local calendar configuration once:

cp assets/js/calendar-config.example.js assets/js/calendar-config.js

Open assets/js/calendar-config.js and insert the browser API key. This file is ignored by Git and must not be committed. Then run:

make serve

Open http://localhost:4000. Stop the server with Ctrl-C.

Check before publishing

make check

This validates internal links, image references, HTML structure, and the files required by GitHub Pages. It uses only Python's standard library.

Publish with GitHub Pages

1. Push main to GitHub.
2. Add the restricted key as an Actions repository secret named GOOGLE_CALENDAR_API_KEY:
   • Open Repository Settings → Secrets and variables → Actions.
   • Select New repository secret.
   • Enter GOOGLE_CALENDAR_API_KEY as the name and paste the key as its value.
3. In Settings → Pages, set Source to GitHub Actions.
4. The Deploy course site workflow publishes every push to main.

API key safety: Never commit assets/js/calendar-config.js, paste the key into index.html, or include it directly in a commit. Before publishing, confirm the key is restricted to the Google Calendar API and to the production GitHub Pages/custom domain plus the approved localhost referrers.

The deployment workflow generates calendar-config.js from the secret. The browser caches the current week's public events for ten minutes. The key is still visible to browsers at runtime—as all static-site browser keys are—so its HTTP-referrer and Google Calendar API restrictions are required.

Relative asset URLs are used throughout, so the same files work at both / locally and /15-441-fa26/ on GitHub Pages.

Updating the course

• Edit announcements, deadlines, and links in index.html.
• Put public downloads in assets/ and link to them with relative paths.
• Keep generated output such as _site/ out of version control.

Links that are not ready are rendered as non-clickable “coming soon” labels. Replace a label with an anchor only when its Fall 2026 destination is ready.