Unlimited boards
Create as many canvas boards as you need — one per project, one per network site, one per protocol. Switch between boards from the sidebar.
Open Learning Workspace
Every feature, documented.
A professional workspace for deep technical mastery — SRE, Kubernetes, DevSecOps, Linux, networking, cryptography, distributed systems, and programming — built for practitioners who learn by doing.
Visual canvas
Draw, diagram, and map your understanding.
Every workspace has one or more Excalidraw canvas boards. Sketch network topologies, call flow diagrams, protocol stacks, or anything else freeform. Boards auto-save as you draw — no manual save needed.
Auto-save
Canvas changes are saved automatically 2 seconds after you stop drawing. No lost work, no manual saves.
Export to image or SVG
Use Excalidraw's built-in export to save any board as a PNG, SVG, or shareable file for documentation or incident reports.
Markdown notes
Structured knowledge, not scattered text.
Notes are written in Markdown and linked to canvas boards or kept standalone. The note editor has a live preview with embedded Mermaid diagram rendering, word count, and auto-save. All notes are searchable and taggable.
Live Markdown preview
Toggle between raw Markdown and a rendered preview at any time. Tables, code blocks, headings, and checklists all render correctly.
Topic color coding
Notes are color-coded by topic in the sidebar: networking (violet — TCP/IPv6/DNS/packets), security (orange — DevSecOps/crypto/detection/supply chain), programming (green — various languages, Web3), systems (rose — SRE/Kubernetes/Linux/distributed). Topics are auto-detected on import.
Auto-save + word count
Notes auto-save every 3 seconds while editing. Word count and estimated reading time appear in the footer.
Full-text search
Search all your notes by title, content, or topic. Results filter the sidebar instantly as you type (Ctrl+/ to focus search).
Tag filtering
Add comma-separated tags to any note. Tag chips appear below the search box — click a tag to filter the note list to matching notes.
Pin important notes
Pin critical reference notes to the top of the list via the right-click context menu. Pinned notes always appear first.
Sort notes
Sort the note list by most recent, alphabetically A–Z, or by mastery level. Sorting applies within the current board filter and respects pinned notes.
Copy note content
One-click copy of the full note Markdown to your clipboard — paste directly into a terminal, ticket, or document without opening preview mode.
Mermaid diagrams in notes
Write a ```mermaid code block in any note and it renders inline as a flowchart, sequence diagram, class diagram, or architecture map. No separate diagramming tool needed.
Templates
Start with structure, not a blank page.
Five built-in templates for networking, VoIP, and security work. Click the ⊞ button in the Notes section to browse templates.
VoIP Incident Investigation
Pre-structured table for environment details, SIP trace observations, RTP analysis, root cause, and resolution. Start filling in fields during the call.
SIP Call Flow
Message sequence table (INVITE → 200 OK → ACK → BYE), key headers to check, and common failure points as a checklist.
Network Topology Notes
Site overview, device inventory table, VLAN layout, routing notes, and firewall observations. Drop in IPs and move on.
TLS / PKI Certificate Audit
Certificate chain table, TLS configuration details, cipher suites, HSTS/OCSP status, findings, and post-quantum readiness assessment.
Troubleshooting Decision Log
Chronological timeline table, evidence collected checklist, hypotheses tested, root cause, fix applied, and follow-up actions.
Flashcards & spaced repetition
Study what you've written. Remember what matters.
Two study modes: Flash for open-ended shuffled practice, and Review for FSRS-scheduled spaced repetition. Review shows only what's due today, asks you to recall before revealing the answer, and adjusts future intervals based on how well you remembered.
FSRS spaced repetition
Review mode uses FSRS-4.5, the current state-of-the-art open-source scheduling algorithm. Cards due today appear with a badge on the toolbar. Rate each card Again / Hard / Good / Easy — the next review date adjusts automatically.
Cued recall
Before revealing the answer, a prompt asks what you recall. Writing it out — even briefly — strengthens memory more than passive reading. Then flip to check against the full note content.
Flashcard study mode
Flash mode lets you browse all notes as a shuffled deck, filtered by topic. Space to flip, arrow keys to navigate, Esc to exit. Markdown, tables, and code blocks render on the back of each card.
Note linking & knowledge graph
See how your knowledge connects.
Link any note to any other note, then click Graph in the toolbar to visualise the whole network. Node size reflects how much content a note has; node colour matches its topic. Click any node to open that note.
Visual knowledge graph
The Graph view uses a force-directed layout to arrange notes by their connections. Zoom, pan, and click any node to jump straight to the note editor. Helpful for spotting isolated notes and well-connected concepts.
Bidirectional links
Links work in both directions — linking note A to note B means B also shows A in its linked notes list. Delete either note and the link is cleaned up automatically.
Search to connect
Click + in the Linked Notes section and type any part of a note title to find and link it. Build a connected map of your technical knowledge over time.
Mastery tracking
Know what you know.
Set a mastery level on any note — Confused, Reviewing, or Comfortable. Colored dots in the sidebar show your progress at a glance. A live progress bar at the bottom of the note list shows the breakdown across all your notes.
😕 Confused
Topics you've encountered but haven't understood yet. Red dot in the sidebar — these need attention first.
🔄 Reviewing
Topics you understand partially and are actively reinforcing. Yellow dot — in progress.
✅ Comfortable
Topics you can explain and apply confidently. Green dot — part of your working knowledge.
Protocol reference
Always one click from the answer.
Click Ref in the canvas toolbar to open the protocol reference panel — five tabs covering everything you need during VoIP and network troubleshooting.
SIP Methods
All 12 SIP methods with RFC numbers, purpose, and key headers — Contact, Via, Record-Route, Session-Expires — with notes on when each matters.
SIP Response Codes
1xx through 6xx — the codes you actually encounter in the field: 401, 403, 480, 486, 488, 503, 603. What they mean and when they appear.
Codecs & Ports
G.711μ/a, G.722, G.729, Opus, iLBC — payload types, bitrates, sample rates, and use cases. Common ports for SIP, RTP, STUN, TURN, H.323.
RTP Quality thresholds
Acceptable/degraded/unacceptable ranges for one-way latency, jitter, packet loss, and MOS — the numbers to quote in escalation tickets.
Troubleshooting checklists
One-way audio, registration failure, dropped calls, and inbound-to-voicemail — the five most common failure modes with structured diagnostic steps.
Wireshark filters
Copy-paste Wireshark display filters for SIP, RTP, DNS, TLS, TCP retransmissions, and more. Plus tcpdump one-liners and Wireshark menu action shortcuts.
Import & export
Your notes, your data.
Import raw text
Paste unstructured work notes, troubleshooting logs, or incident summaries. The importer splits them by blank lines or Markdown headings and auto-detects the topic from keywords.
Export all notes
Download all your notes as a single Markdown file at any time — title, topic, tags, and full content, separated by horizontal rules. No lock-in.
Duplicate notes
Right-click any note and choose Duplicate to create a copy — useful for starting from a template note or creating variations of a standard investigation structure.
Keyboard shortcuts
Built for keyboard-first workflows.
Note shortcuts
Ctrl+N — New note. Ctrl+S — Save current note. Esc — Save and close editor. Ctrl+/ — Focus search box. All work without leaving the keyboard.
Flashcard shortcuts
Space — Flip card. → / ← — Next / previous card. Esc — Exit flashcard mode.
Workspace shortcuts
? — Open keyboard shortcut reference. Esc — Close any open modal. Canvas shortcuts (H, V, R, E, A, T, Ctrl+Z) follow Excalidraw defaults.
Security & privacy
Your notes stay yours.
Authenticated access
The workspace requires a NetHero platform account. Authentication uses Google OAuth 2.0 with session cookies — no passwords stored.
Per-user isolation
Every board, note, and link is scoped to your user ID. No user can read or modify another user's data — enforced at the database query level, not just the API.
Safe Markdown rendering
Note preview uses marked.js for Markdown parsing and DOMPurify for HTML sanitization — industry-standard libraries that prevent XSS from note content.
Get started
Open the workspace now.
Available to all NetHero platform users. Sign in with your Google account to get started.