RFC-TENANT-SECURITY-0001                                         Section 2
Category: Standards Track                                     Requirements

Goal	Description
Defense in Depth	Multiple independent security layers such that compromise of one layer does not compromise the system
Zero Trust Posture	No implicit trust; all traffic must be explicitly authorized
OWASP Protection	Mitigate OWASP Top 10 and API Security Top 10 risks at the network layer
Tenant Isolation	Prevent cross-tenant communication unless explicitly permitted
Operational Simplicity	Centralized management with minimal operational burden

2.1.2 Secondary Goals

Goal	Description
GitOps Native	All security policies defined in version control
Observable	Security events integrated with monitoring and alerting
Auditable	Controls documented for compliance requirements
Extensible	Architecture accommodates future security capabilities

2.2 Non-Goals

Non-Goal	Rationale	Alternative
Application-level authorization	Business logic belongs in applications	RFC-IAM-0001 provides patterns
Service-to-service authentication	East-West traffic handled separately	RFC-WORKLOAD-IDENTITY
Secret management	Secrets have dedicated architecture	RFC-SECOPS-0001
DDoS mitigation at network layer	Requires infrastructure-level controls	Cloud provider or CDN
Content inspection beyond HTTP	Deep packet inspection out of scope	Specialized tools if required

2.3 Architectural Invariants

Invariants are rules that MUST always hold true. Violation of an invariant indicates a system failure or misconfiguration.

2.3.1 Traffic Protection Invariants

Invariant 1 — WAF Coverage

All external HTTP and HTTPS traffic MUST pass through the Web Application Firewall before reaching application workloads. Traffic that bypasses the WAF MUST NOT reach applications.

Aspect	Requirement
Scope	All ingress HTTP/HTTPS traffic
Enforcement	Ingress architecture
Violation Impact	Applications exposed to unfiltered attacks

Invariant 2 — TLS Minimum Version

All public endpoints MUST use TLS 1.2 or higher. TLS 1.0 and TLS 1.1 MUST NOT be accepted for any public-facing service.

Aspect	Requirement
Scope	All public endpoints
Enforcement	Ingress TLS configuration
Violation Impact	Cryptographic weakness exposure

Invariant 3 — Certificate Automation

Certificate provisioning for production endpoints MUST be automated. Manual certificate installation MUST NOT be used for production endpoints.

Aspect	Requirement
Scope	Production TLS certificates
Enforcement	cert-manager automation
Violation Impact	Certificate expiry incidents

Invariant 4 — WAF Detection Before Enforcement

New WAF rule sets MUST operate in detection mode before enforcement mode is enabled. Direct deployment to enforcement mode MUST NOT occur without a detection period.

Aspect	Requirement
Scope	WAF rule deployment
Enforcement	Operational procedure
Violation Impact	False positive outages

2.3.2 Network Policy Invariants

Invariant 5 — Default Deny Ingress

All tenant namespaces MUST have a default-deny ingress network policy. Traffic to pods MUST be explicitly allowed; implicit allow MUST NOT exist.

Aspect	Requirement
Scope	All tenant namespaces
Enforcement	NetworkPolicy resources
Violation Impact	Unauthorized access possible

Invariant 6 — Explicit Cross-Namespace Authorization

Cross-namespace traffic MUST be explicitly authorized through network policies. Implicit cross-namespace access MUST NOT exist.

Aspect	Requirement
Scope	All namespace boundaries
Enforcement	NetworkPolicy resources
Violation Impact	Lateral movement possible

Invariant 7 — Controlled Egress

Egress to the public internet from tenant namespaces MUST be controlled. Unrestricted egress MUST NOT be permitted from tenant workloads.

Aspect	Requirement
Scope	Tenant namespace egress
Enforcement	NetworkPolicy resources
Violation Impact	Data exfiltration paths

Invariant 8 — Guardrail Policy Precedence

Platform guardrail policies MUST NOT be overridable by tenant-level policies. Guardrails MUST take precedence over tenant policies.

Aspect	Requirement
Scope	Platform security policies
Enforcement	Policy hierarchy
Violation Impact	Security bypass

2.3.3 Observability Invariants

Invariant 9 — Blocked Request Logging

All blocked requests MUST be logged with sufficient context for incident response. Context MUST include source IP, target, rule triggered, and timestamp.

Aspect	Requirement
Scope	WAF and network policy blocks
Enforcement	Logging configuration
Violation Impact	Incident response hindered

Invariant 10 — Network Flow Observability

Network flow data MUST be observable for troubleshooting and audit purposes. Flow logs MUST be available for security analysis.

Aspect	Requirement
Scope	All cluster network traffic
Enforcement	CNI observability features
Violation Impact	Troubleshooting blind spots

Invariant 11 — Monitoring Integration

WAF security events MUST be integrated with the platform monitoring and alerting system. Critical security events MUST trigger alerts.

Aspect	Requirement
Scope	WAF security events
Enforcement	Monitoring integration
Violation Impact	Delayed incident detection

2.3.4 GitOps Invariants

Invariant 12 — Policy Version Control

Network policy definitions MUST be stored in Git and applied via GitOps. Manual policy creation outside Git MUST NOT be used for production.

Aspect	Requirement
Scope	All network policies
Enforcement	GitOps workflow
Violation Impact	Configuration drift, audit gaps

Invariant 13 — WAF Rule Version Control

WAF rule customizations MUST be version controlled. Ad-hoc rule changes MUST NOT be made outside version control.

Aspect	Requirement
Scope	WAF rule customizations
Enforcement	GitOps workflow
Violation Impact	Untracked security changes

Invariant 14 — Automated Secret Management

TLS secrets MUST be managed via automated systems (cert-manager or ESO). Manual secret creation MUST NOT be used for TLS certificates.

Aspect	Requirement
Scope	TLS certificate secrets
Enforcement	Automation tooling
Violation Impact	Secret sprawl, expiry incidents

2.4 Invariant Summary

ID	Category	Statement
INV-1	Traffic	All external HTTP/HTTPS traffic MUST pass through WAF
INV-2	Traffic	All public endpoints MUST use TLS 1.2+
INV-3	Traffic	Certificate provisioning MUST be automated
INV-4	Traffic	WAF rules MUST operate in detection before enforcement
INV-5	Network	All tenant namespaces MUST have default-deny ingress
INV-6	Network	Cross-namespace traffic MUST be explicitly authorized
INV-7	Network	Egress to internet MUST be controlled
INV-8	Network	Platform guardrails MUST NOT be overridable
INV-9	Observability	All blocked requests MUST be logged
INV-10	Observability	Network flows MUST be observable
INV-11	Observability	WAF events MUST integrate with monitoring
INV-12	GitOps	Network policies MUST be in Git
INV-13	GitOps	WAF customizations MUST be version controlled
INV-14	GitOps	TLS secrets MUST be automated

2.5 Success Criteria

2.5.1 Security Criteria

Criterion	Measurement
OWASP Top 10 coverage	WAF blocks all standard OWASP test payloads
Zero trust enforcement	No implicit allow policies exist
Tenant isolation	Cross-namespace probes fail by default
Bot mitigation	Challenge mechanisms activate for suspicious traffic

2.5.2 Operational Criteria

Criterion	Measurement
Certificate automation	Zero manual certificate operations
Policy drift	Git state matches cluster state
Alert coverage	Critical events trigger notifications
Recovery time	WAF mode can be toggled within defined threshold

2.5.3 Compliance Criteria

Criterion	Measurement
SOC 2 CC6.6	WAF controls documented
PCI DSS 6.6	WAF implementation evidence
ISO 27001 A.13.1	Network segmentation documentation

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End of Section 2

2. Requirements