🧩 SSDP+
SSDP+ is the patented Secure Share Distribution Protocol that powers Inheriti® Business: the business-grade evolution of the SSDP protocol behind Inheriti®.
How it protects data
- Encrypt: your data is encrypted in your browser with a unique AES-256 key, before anything leaves it.
- Split: both the encrypted data and its key are divided into shares using Shamir's Secret Sharing. Every share is useless on its own.
- Distribute: the shares are spread across separate storage layers, so no single location ever holds enough to reconstruct anything.
- Controlled recovery: only authorised members can recombine shares, and only after your governance rules approve the request.
What makes SSDP+ different from SSDP
SSDP+ extends SSDP with three additions:
- An authenticated AES-GCM-256 encryption layer beneath the secret sharing: every share is encrypted and integrity-protected before it is stored.
- Key shares, distributed independently of data shares: SSDP splits the data only. SSDP+ also splits the encryption key, and the two kinds of shares travel and live independently.
- Native binary payloads: not just text secrets. Documents, images and video are first-class data.
Together these change what the protocol can carry. Because the heavy data shares stay in storage and a member's device only ever holds a light key share, SSDP+ can protect media assets and files, not just short secrets.
The custodian position
Every plan includes a custodian share pair: one custodian data share and one custodian key share. The merge threshold always includes the custodian position, which changes what an attacker would need.
- The custodian data share stays in the custodian depot, built on the Inheriti® Vault.
- The custodian key share is claimed to a member's SafeKey Mobile or SafeKey Pro, and released by hand when an approved reveal needs it.
This is also where SSDP+ departs from SSDP in daily use: in SSDP the custodian claims the full data share to their device; in SSDP+ they claim only the key share, while storage does the heavy lifting.
Because that key share lives on a device in someone's pocket and is released by hand, no purely remote compromise can complete a reveal.
What creating a plan produces
Every plan creation run produces four kinds of artifacts, each with its own destination:
| Artifact | What it is | Where it lives |
|---|---|---|
| Data shares | Pieces of the encrypted data | Inheriti® Vault, and your custom layers where enabled |
| Validator key shares | Pieces of the encryption key | Your organisation's smart contract on InheritiChain |
| Custodian share pair | One extra data share and key share, pulled out of the regular distribution | Data share in the custodian depot; key share on a member's SafeKey Mobile or SafeKey Pro |
| Plan key | The per-plan key that encrypts every share above | Stored only as ciphertext, wrapped by your Organisation Key and sealed by the Inheriti® HSM |
Two keys, two layers
SSDP+ deliberately uses two distinct symmetric keys per plan:
- The SSDP+ key works at the protocol layer: it encrypts the data itself, and it is the key that gets split. Splitting the key alongside the data is what gives the shares their diversity.
- The plan key works one layer up: it encrypts every share before storage, acting as a per-plan stamp. It is the key the Organisation Key and the HSM protect.
So even a share retrieved from storage is double-locked: encrypted by the plan key, and meaningless without enough sibling shares to rebuild the SSDP+ key.
Intellectual property
The general workings of SSDP are public; the exact algorithms and distribution logic are proprietary. The protocol is patented in multiple jurisdictions, including the US, EU and China. See the patent overview on the consumer documentation.