SA260324R-0243_r1

SA260324R-0243

① SA Source

• Source: 開啟完整 SA 文章
• Section: Oberon and Kyber Updates, Larger World Sizes Introduced, More Networking Updates
• Line hint: 304

Context Before

Each 28.8T NVLink Switch has 144 lanes of 200G (simultaneous bi-directional) which means each Switch has 24 lanes of 200G going to each connector. Copper flyover cables are used to connect each switch to the midplane, as the distances involved are too long for PCB traces.

Evidence

This is also why the switches are further away from the midplane, to provide space for the routing of the flyover cables.

Context After

Each NVLink Switch Chip connects via flyover cables to the connector (144 DPs used x 200 Gbit/s bi-di channel = 28.8Tbit/s) connectors at the edge of the switch blade, and these connectors plug into the midplane board. Nvidia is looking into using co-packaged Copper to reduce loss further, in case NPC doesn’t work. As far as we know Nvidia is telling supply chain to go for fully co-packaged copper.

② Atomic Claim

這也是 switch 與 midplane 距離較遠的原因，以便留下空間配置 flyover cable。

• Epistemic Mode: ASSERTED
• Mapping Status: PARTIAL

③ Semantic Frame

{
  "frame_type": "NARY_RELATION",
  "participants": [
    {
      "node": {
        "id": "04_knowledge_base/Midplane",
        "label": "midplane"
      },
      "role": "midplane"
    },
    {
      "node": {
        "id": "04_knowledge_base/Flyover cable",
        "label": "flyover cable"
      },
      "role": "cable"
    }
  ],
  "qualifiers": {
    "condition_text": "switch 沒有 canonical entity",
    "numeric_mentions": [],
    "temporal_mentions": []
  },
  "relation_type": "SPACES_SWITCH_FOR_FLYOVER_ROUTING"
}

④ Canonical Entity Mapping

Role	Surface Label	Canonical Target
midplane	midplane	Midplane
cable	flyover cable	04_knowledge_base/Flyover cable

⑤ Human Review

請在 Properties 逐項確認：

• 原文 → Atomic Claim 是否忠實
• Atomic Claim → Semantic Frame 是否忠實
• Canonical Entity mapping 是否正確
• Epistemic mode 是否保留原文語氣
• 最後選擇 review_action

Review state

Markdown 內文不是正式 approval。只有 Apply bridge 寫入的 Decision Ledger event 才是正式決策。