{
  "id": "bbg-p0423-grpc-and-service-communication-service",
  "title": "DNS Resolution Chain",
  "chapter": "web-request-lifecycle",
  "batch": "20",
  "rank": 200,
  "sourcePage": 423,
  "sourcePointer": "p. 423",
  "status": "accepted",
  "reviewerStatus": "reviewed",
  "fidelityScore": 0.9,
  "canvas": {
    "width": 960,
    "height": 640
  },
  "fireworksTechGraph": {
    "style": "style-1-flat-icon",
    "diagramType": "network-topology",
    "topologyNotes": [
      "source page render inspected",
      "extracted page text inspected",
      "source page render inspected",
      "preserve DNS lookup sequence: browser and resolver caches, recursive resolver, root, TLD, authoritative server, returned IP, HTTP request to web server",
      "retargeted from service-communication extraction to web-request-lifecycle chapter"
    ],
    "publicBoundary": [
      "original vector output",
      "no source pixels",
      "no source mark or long wording"
    ]
  },
  "callouts": [],
  "sourceReview": {
    "conceptAnchors": [
      "concept: browser cache",
      "concept: resolver cache",
      "concept: root server",
      "concept: TLD server",
      "concept: authoritative server",
      "concept: web server response"
    ],
    "labelSource": "curated",
    "semanticStatus": "reviewed"
  },
  "groups": [
    {
      "id": "client",
      "label": "Client side",
      "x": 48,
      "y": 124,
      "w": 214,
      "h": 352
    },
    {
      "id": "resolver",
      "label": "Recursive resolution",
      "x": 312,
      "y": 124,
      "w": 292,
      "h": 352
    },
    {
      "id": "authority",
      "label": "Name authority and origin",
      "x": 656,
      "y": 124,
      "w": 252,
      "h": 352
    }
  ],
  "shapes": [
    {
      "id": "user",
      "kind": "actor",
      "label": "User",
      "detail": "domain",
      "x": 90,
      "y": 154,
      "w": 82,
      "h": 86,
      "tone": "blue"
    },
    {
      "id": "browser",
      "kind": "rect",
      "label": "Browser",
      "detail": "cache check",
      "x": 86,
      "y": 274,
      "w": 112,
      "h": 58,
      "tone": "teal"
    },
    {
      "id": "oscache",
      "kind": "cylinder",
      "label": "OS cache",
      "detail": "local IP",
      "x": 86,
      "y": 388,
      "w": 112,
      "h": 74,
      "tone": "orange"
    },
    {
      "id": "resolver",
      "kind": "gateway",
      "label": "Resolver",
      "detail": "recursive",
      "x": 394,
      "y": 256,
      "w": 124,
      "h": 84,
      "tone": "green"
    },
    {
      "id": "resolverCache",
      "kind": "cylinder",
      "label": "Resolver cache",
      "detail": "hit miss",
      "x": 394,
      "y": 382,
      "w": 124,
      "h": 74,
      "tone": "orange"
    },
    {
      "id": "root",
      "kind": "rect",
      "label": "Root DNS",
      "detail": "NS referral",
      "x": 678,
      "y": 156,
      "w": 112,
      "h": 58,
      "tone": "purple"
    },
    {
      "id": "tld",
      "kind": "rect",
      "label": "TLD DNS",
      "detail": "domain zone",
      "x": 678,
      "y": 276,
      "w": 112,
      "h": 58,
      "tone": "purple"
    },
    {
      "id": "auth",
      "kind": "rect",
      "label": "Authoritative",
      "detail": "IP record",
      "x": 678,
      "y": 394,
      "w": 112,
      "h": 58,
      "tone": "purple"
    },
    {
      "id": "web",
      "kind": "rect",
      "label": "Web server",
      "detail": "HTTP OK",
      "x": 808,
      "y": 276,
      "w": 88,
      "h": 58,
      "tone": "green"
    }
  ],
  "connectors": [
    {
      "from": "user",
      "to": "browser",
      "label": "enter",
      "flow": "main"
    },
    {
      "from": "browser",
      "to": "oscache",
      "label": "local",
      "flow": "data"
    },
    {
      "from": "browser",
      "to": "resolver",
      "label": "query",
      "flow": "main"
    },
    {
      "from": "resolver",
      "to": "resolverCache",
      "label": "lookup",
      "flow": "data"
    },
    {
      "from": "resolver",
      "to": "root",
      "label": "ask",
      "flow": "main"
    },
    {
      "from": "root",
      "to": "tld",
      "label": "refer",
      "flow": "main"
    },
    {
      "from": "tld",
      "to": "auth",
      "label": "refer",
      "flow": "main"
    },
    {
      "from": "auth",
      "to": "resolver",
      "label": "IP",
      "flow": "data",
      "dashed": true
    },
    {
      "from": "resolver",
      "to": "browser",
      "label": "return IP",
      "flow": "data"
    },
    {
      "from": "browser",
      "to": "web",
      "label": "HTTP",
      "flow": "main"
    }
  ]
}