# Startrail IPFS CDN gateway

Startrail runs a managed IPFS gateway on top of a CDN at:

```
https://cdn.startrail.io/ipfs/<cid>
```

This is the **recommended** gateway for resolving any IPFS CID surfaced by the Startrail platform — including:

* SRR metadata JSON (`metadataDigest` / `metadataCID` returned by the [subgraph](/subgraph/subgraph.md), the [Get SRR endpoints](/get-srr-api/description-of-srr-data.md), and the [Issue & Transfer endpoint](/issue-transfer-api/issue-and-transfer-srr-nft/issue-and-transfer.md))
* Image URLs inside SRR metadata (`thumbnailURL`, `image`, `external_url` when they reference an `ipfs://` or CID URL)
* Attachment files (`attachmentFiles[*]`) and digital components (`digitalComponents[*]`) referenced by their CID/hash

It returns the same content as any other public IPFS gateway, but with lower latency, better availability for Startrail-pinned content, and consistent CORS / cache behavior.

## Usage

Given a CID such as `bafkreiabepvyxyetkcb3xbjo3ocuyfo6psv3rc3yj34hequwcsilyvjima`, fetch it as:

```
https://cdn.startrail.io/ipfs/bafkreiabepvyxyetkcb3xbjo3ocuyfo6psv3rc3yj34hequwcsilyvjima
```

For metadata returned by the [Issue & Transfer endpoint](/issue-transfer-api/issue-and-transfer-srr-nft/issue-and-transfer.md), the response already includes a ready-to-use URL:

```json
{
  "results": [{
    "srr": {
      "tokenId": "227890056407",
      "metadataCID": "bafkrei...",
      "metadataURL": "https://cdn.startrail.io/ipfs/bafkrei..."
    }
  }]
}
```

## When the CID starts with `0x`

For SRRs issued before 2023, the `metadataDigest` may be a 32-byte hex string starting with `0x` rather than a CID. In that case the metadata is **not** available on IPFS; fetch it from the Startrail API instead via [Get Metadata by Token ID](/startrail-api/get-metadata-by-token-id.md).

## Other gateways

If for any reason you need an alternative, the same CID can be served by any public IPFS gateway (e.g. Cloudflare, Storacha, etc.). See [How to retrieve SRR metadata](/subgraph/how-to-retrieve-metadata.md) for examples. We still recommend the Startrail gateway for production traffic.


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