BGP AS-Path Sunburst

A zero-dependency bookmarklet that visualises BGP AS-path data from bgp.tools/super-lg as an interactive zoomable sunburst chart, rendered on an HTML5 Canvas.

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Installation

1. Open install.html
2. Drag the button into your browser bookmark bar, or right-click it and save to bookmarks.

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Usage

1. Go to bgp.tools/super-lg and search for any prefix (e.g. 8.8.8.0/24)
2. Click the BGP Sunburst bookmark
3. A full-screen overlay appears immediately — no network requests, no loading

Interaction	Action
Click arc	Zoom into that subtree
Click centre	Zoom out one level
Hover	Tooltip: org name · path count · BGP communities
✕ button	Close overlay

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How it works

Collector peer → … → transit AS → … → origin AS (centre)

The chart is rooted at the origin AS (the AS that announces the searched prefix). Each concentric ring represents one more transit hop outward toward the collecting peers. Arc width is proportional to the number of observed paths flowing through that segment.

Data pipeline

DOM walk (TreeWalker)
  │
  ├─ BGP.as_path: <abbr title="Org">ASN</abbr> …   → path array + org names
  ├─ BGP.community: (x,y) <abbr>[decoded]</abbr>   → community strings per ASN
  └─ BGP.large_community: <abbr>[decoded]</abbr>   → large community strings
        │
        ▼
  Deduplicate consecutive ASNs (collapse prepend padding)
        │
        ▼
  Build trie (origin → transit → collector)
        │
        ▼
  Assign arc angles proportional to path count
        │
        ▼
  Render on HiDPI-aware Canvas 2D

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Files

File	Description
bgp_sunburst.js	Full source with comments — the canonical version
install.html	Open in Firefox to get the drag-and-drop bookmarklet button
screenshot.png	Preview image

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License

MIT