# Cryptography Concept and Key Management

| Document information | Value |
|-----------------------|------|
| Document type | Procedure instruction (VA-07) |
| Scope | {{ISMS_SCOPE}} |
| Organisation | {{ORG_NAME}} |
| Process owner | {{ROLE_IT_LEAD}} |
| Approved by | {{ROLE_ISB}} |
| Version | {{DOC_VERSION}} |
| Date | {{DOC_DATE}} |
| Status | {{DOC_STATUS}} |

<!-- FULFILLS 5.1.1-M1, 5.1.1-M2, 5.1.1-S1, 5.1.2-M1, 5.1.2-S1, A.8.24-1 | POLICY R09 -->

## 1. Purpose

This procedure governs the use of cryptographic procedures and the management of keys throughout the lifecycle. It operationalises the associated policy ({{LINK:R09}}).

## 2. Scope

Applies within the ISMS scope ({{ISMS_SCOPE_DESCRIPTION}}).

## 3. Trigger

New need for encryption/certificates; key renewal/revocation; change in the state of the art.

## 4. Inputs

- Permissible algorithms (BL-CRY-02)
- Protection need of the data
- Certificate/key inventory

## 5. Process

1. Determine need & procedure: select permissible algorithms {{CRYPTO_ALGO}} (BL-CRY-02).
2. Generate keys/certificates and distribute them securely (BL-CRY-05).
3. Storage & access protection (separate storage, {{#if FLAG_CRYPTO_PKI}}PKI, {{/if}}authorisations).
4. Ensure transmission protection: at least {{TLS_MIN}} (BL-CRY-01).
5. Document renewal/revocation/destruction.

## 6. RACI

| # | Step | R (Execution) | A (Accountable) | C (Consulted) | I (Informed) |
|---|---------|------------------|------------------|-----------------|----------------|
| 1 | Determine need & procedure | {{ROLE_IT_LEAD}} | {{ROLE_ISB}} | - | - |
| 2 | Generate keys/certificates and distribute securely | {{ROLE_IT_LEAD}} | {{ROLE_IT_LEAD}} | - | - |
| 3 | Storage & access protection (separate storage) | {{ROLE_IT_LEAD}} | {{ROLE_ISB}} | - | - |
| 4 | Ensure transmission protection | {{ROLE_IT_LEAD}} | {{ROLE_IT_LEAD}} | - | - |
| 5 | Document renewal/revocation/destruction | {{ROLE_IT_LEAD}} | {{ROLE_ISB}} | - | - |

## 7. Result & evidence

Documented cryptography concept; traceable key/certificate lifecycle. Evidence is referenced in the central evidence register ({{LINK:NACHWEISREGISTER}}).

## 8. Key performance indicators (KPI)

- Share of compliant procedures/algorithms
- Expiring certificates without renewal
- Coverage of transport encryption

## 9. Related documents

- Associated policy: {{LINK:R09}}
- {{LINK:VA-04}}
- Technical security baseline: {{LINK:BASELINE}}
- ISA mapping matrix: {{LINK:ISA_MAPPING}}

<!-- Erfüllt die oben unter FULFILLS gelisteten Anforderungen; Kopplung in mapping.json. Im Lesemodus nicht sichtbar. -->