# RPC Verification Memo – Chain 138 (Defi Oracle Meta Mainnet)

**Last Updated:** 2026-01-31  
**Document Version:** 1.0  
**Status:** Active Documentation

---

**Date**: 2026-01-29  
**Audience**: Partners, auditors, operators  
**Classification**: Technical verification summary (one page)

---

## 1. Stack overview

```
Internet / LAN
      │
      ▼
DNS (rpc-http-pub.d-bis.org, rpc.d-bis.org, rpc2.d-bis.org, rpc.defi-oracle.io, etc.) → 76.53.10.36
      │
      ▼
UDM Pro port forward 76.53.10.36:443 → 192.168.11.167:443
      │
      ▼
NPMplus (192.168.11.167:443) – TLS termination, Host-based routing
      │
      ▼
Besu RPC – VMID 2201 (192.168.11.221:8545 HTTP, :8546 WebSocket)
      │
      ▼
Response: eth_chainId → 0x8a (Chain ID 138)
```

---

## 2. Validation results

| Check | Result |
|-------|--------|
| **DNS** | Public hostnames resolve to 76.53.10.36 |
| **TLS** | Valid Let's Encrypt; CN matches hostname; TLS 1.3 |
| **Proxy** | NPMplus routes by Host to VMID 2201 |
| **Upstream** | Besu RPC (192.168.11.221:8545 / :8546) reachable and responsive |
| **RPC** | `eth_chainId` returns `0x8a` (138) |
| **Chain** | Defi Oracle Meta Mainnet – sovereign EVM, no mainnet/testnet collision |

**Validation command** (from a host that can reach NPMplus, e.g. LAN with Split DNS or `--resolve`):

```bash
curl -sk --resolve rpc-http-pub.d-bis.org:443:192.168.11.167 \
  https://rpc-http-pub.d-bis.org \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_chainId","params":[],"id":1}'
# Expected: {"jsonrpc":"2.0","id":1,"result":"0x8a"}
```

---

## 3. Public endpoints

| Endpoint | Type | Backend |
|----------|------|---------|
| https://rpc-http-pub.d-bis.org | HTTP RPC | 192.168.11.221:8545 |
| wss://rpc-ws-pub.d-bis.org | WebSocket RPC | 192.168.11.221:8546 |
| https://rpc.d-bis.org | HTTP RPC | 192.168.11.221:8545 |
| https://rpc2.d-bis.org | HTTP RPC | 192.168.11.221:8545 |
| wss://ws.rpc.d-bis.org | WebSocket RPC | 192.168.11.221:8546 |
| wss://ws.rpc2.d-bis.org | WebSocket RPC | 192.168.11.221:8546 |
| https://rpc.defi-oracle.io | HTTP RPC | 192.168.11.221:8545 |
| wss://wss.defi-oracle.io | WebSocket RPC | 192.168.11.221:8546 |

**Explorer**: https://explorer.d-bis.org  
**Chain ID**: 138 (`0x8a`)

---

## 4. Operational notes

- **LAN access**: From inside the same network, public hostnames may not resolve back (NAT hairpin). Use Split DNS (internal A records to 192.168.11.167) or the `--resolve` curl pattern for testing.
- **Port forwarding**: 76.53.10.36:80 and :443 → 192.168.11.167 (NPMplus). Confirmed on UDM Pro.
- **No auth**: Public RPC endpoints do not require API keys or auth.

---

## 5. References

- **Verification detail**: `RPC_CHAIN138_VERIFICATION.md`
- **Wallet/SDK configs**: `CHAIN138_WALLET_CONFIG_VALIDATION.md`
- **IDS/IPS and WebSockets**: `IDS_IPS_WEBSOCKET_GUIDANCE.md`