# Sankofa Phoenix: System Architecture

## Technical Nexus

**Sankofa Ltd** serves as the technical nexus for all system operations and integrations, functioning as the central hub for infrastructure, data exchange, and platform orchestration. All computing resources, hosting environments, and cloud-based services that support Sankofa's technical operations are powered by **Phoenix**, which acts as the dedicated cloud service provider. ([Reference: https://sankofa.nexus](https://sankofa.nexus))

## Overview

Sankofa Phoenix is a multi-tier, globally distributed cloud infrastructure platform combining edge computing, regional datacenters, and core blockchain infrastructure. The architecture supports a 325-region global deployment with enterprise-grade blockchain capabilities for supply chain, identity, compliance, and resource management.

**Sankofa Phoenix** is the sovereign cloud platform of the **Sankofa** ecosystem, delivering compute, storage, networking, identity, security, AI, and marketplace services. All infrastructure, data exchange, and platform orchestration operations are coordinated through Sankofa Ltd as the technical nexus, with Phoenix providing the underlying cloud infrastructure and services.

## Architecture Tiers

### Tier 1: Core Datacenters (Hub Sites)
**Purpose**: Primary infrastructure hubs for blockchain consensus, core services, and global coordination.

**Components**:
- Blockchain validator nodes (3-5 per datacenter)
- Kubernetes control plane clusters
- Core database clusters (PostgreSQL)
- Message queue clusters (Kafka/Redpanda)
- Object storage (MinIO/Ceph)
- Identity and access management (Keycloak/OkraID)

**Deployment**: 10-15 strategic locations globally

**See**: [Datacenter Architecture](./datacenter_architecture.md) for detailed specifications

### Tier 2: Regional Datacenters (Spoke Sites)
**Purpose**: Regional aggregation points, blockchain read replicas, and regional service delivery.

**Components**:
- Blockchain read replica nodes (2-3 per datacenter)
- Regional Kubernetes clusters
- Regional database replicas
- CDN edge nodes
- Regional API gateways

**Deployment**: 50-75 locations globally

**See**: [Datacenter Architecture](./datacenter_architecture.md) for detailed specifications

### Tier 3: Edge Sites (Edge Computing)
**Purpose**: Low-latency compute at the network edge.

**Components**:
- Proxmox VE clusters
- Light blockchain client nodes
- Edge compute nodes
- Local storage
- Cloudflare Tunnel agents

**Deployment**: 250+ locations globally

**See**: Existing edge implementation documentation in `docs/architecture/`

## Blockchain Architecture

### Enterprise Ethereum Alliance (EEA) Implementation

**Network Type**: Private, permissioned blockchain
**Consensus**: Proof of Authority (PoA) or Proof of Stake (PoS)
**Purpose**: Enterprise use cases (NOT cryptocurrencies)

**Key Components**:
- Validator nodes in Tier 1 core datacenters
- Read replica nodes in Tier 2 regional datacenters
- Light client nodes in Tier 3 edge sites
- Smart contracts for:
  - Resource provisioning and tracking
  - Supply chain provenance
  - Identity and access management
  - Billing and settlement
  - Compliance and auditing
  - SLA enforcement

**See**: [Blockchain EEA Architecture](./blockchain_eea_architecture.md) for detailed specifications

## System Components

### Control Plane

**Location**: Tier 1 and Tier 2 datacenters

**Components**:
- **Kubernetes**: Container orchestration
- **Crossplane**: Infrastructure as Code
- **ArgoCD**: GitOps deployment
- **Keycloak**: Identity and access management
- **Vault**: Secrets management
- **Prometheus/Grafana**: Monitoring and observability
- **Loki**: Log aggregation

**Integration**:
- All control plane operations recorded on blockchain
- Resource provisioning tracked via smart contracts
- Identity management integrated with blockchain identity layer

### Networking

**Global Network**:
- **Cloudflare Zero Trust**: Secure access layer
- **Cloudflare Tunnels**: Outbound-only connections
- **Inter-Datacenter Links**: 100Gbps+ between core datacenters
- **Regional Links**: 10-40Gbps to regional datacenters
- **Edge Connectivity**: High-speed internet with redundancy

**Blockchain Network**:
- **Private P2P Network**: Encrypted peer-to-peer connections
- **Network Overlay**: VPN or dedicated network segment
- **Consensus Communication**: Secure channels for validators

### Storage

**Tier 1 Core Datacenters**:
- Blockchain state storage: 50-100TB per datacenter
- Application data: 500TB-1PB per datacenter
- Object storage: 5-10PB per datacenter
- Backup storage: 2x primary capacity

**Tier 2 Regional Datacenters**:
- Primary storage: 100-500TB per datacenter
- Object storage: 200TB-1PB per datacenter
- Blockchain state cache: 10-20TB per datacenter

**Tier 3 Edge Sites**:
- Local storage: 40-200TB per site (as per edge implementation)

**Storage Technologies**:
- Ceph for distributed block/object storage
- ZFS for high-performance local storage
- MinIO for S3-compatible object storage
- LevelDB/RocksDB for blockchain state

### Compute

**Tier 1 Core Datacenters**:
- Blockchain validators: High-performance CPUs, 64-128GB RAM
- Kubernetes clusters: 3 master + 5 worker nodes minimum
- Database clusters: PostgreSQL with replication
- Message queues: Kafka/Redpanda clusters

**Tier 2 Regional Datacenters**:
- Blockchain read replicas: 32-64GB RAM
- Kubernetes clusters: 3 master + 3 worker nodes
- Regional services: API gateways, CDN nodes

**Tier 3 Edge Sites**:
- Proxmox clusters: As per edge implementation
- Edge compute: Low-latency processing

## Data Flow

### Resource Provisioning Flow

1. **User Request**: User requests resource via portal
2. **Control Plane**: Kubernetes/Crossplane processes request
3. **Blockchain Recording**: Resource provisioning recorded on blockchain via smart contract
4. **Infrastructure**: Resource provisioned in appropriate tier (edge/regional/core)
5. **Verification**: Multi-party verification via blockchain
6. **Monitoring**: Resource usage tracked and recorded

### Identity and Access Flow

1. **Identity Registration**: User identity registered on blockchain
2. **Authentication**: User authenticates via Keycloak/OkraID
3. **Blockchain Verification**: Identity verified via blockchain
4. **Access Grant**: Access granted based on verified identity
5. **Cross-Region**: Identity federation across regions via blockchain

### Supply Chain Flow

1. **Component Registration**: Hardware component registered on blockchain
2. **Transfer Tracking**: Each transfer recorded immutably
3. **Deployment Recording**: Component deployment recorded
4. **Compliance Verification**: Compliance checks verified via blockchain
5. **Audit Trail**: Complete history available for audit

### Billing and Settlement Flow

1. **Usage Tracking**: Resource usage tracked and recorded
2. **Blockchain Recording**: Usage data stored on blockchain
3. **Invoice Generation**: Smart contract generates invoice
4. **Multi-Party Verification**: Billing verified by multiple parties
5. **Automated Settlement**: Settlement executed via smart contract

## Security Architecture

### Physical Security
- Biometric access control
- 24/7 surveillance
- Fire suppression systems
- Environmental monitoring
- SOC 2, ISO 27001 compliance

### Network Security
- Network segmentation by tier
- TLS/SSL encryption for all connections
- Next-generation firewalls
- Multi-layer DDoS protection
- Zero Trust networking

### Blockchain Security
- Hardware Security Modules (HSMs) for validators
- Secure key management and rotation
- Permissioned blockchain with RBAC
- Smart contract security audits
- Emergency pause mechanisms

### Application Security
- OAuth2/JWT authentication
- Role-based access control (RBAC)
- Secrets management (Vault)
- Regular security audits
- Vulnerability scanning

## Integration Points

### Edge to Regional Integration
- Edge sites report metrics to regional datacenters
- Regional datacenters aggregate and process data
- Blockchain read replicas serve edge queries

### Regional to Core Integration
- Regional datacenters sync with core datacenters
- Core datacenters maintain blockchain consensus
- Global coordination via core datacenters

### Blockchain Integration
- All critical operations recorded on blockchain
- Smart contracts enforce policies and agreements
- Immutable audit trail for compliance
- Multi-party verification for transparency

### Control Plane Integration
- Kubernetes integrated with blockchain for resource tracking
- Crossplane provisions infrastructure with blockchain recording
- ArgoCD deployments tracked on blockchain
- Identity management integrated with blockchain identity layer

## Monitoring and Observability

### Infrastructure Monitoring
- **Prometheus**: Metrics collection
- **Grafana**: Visualization and dashboards
- **Loki**: Log aggregation
- **Alertmanager**: Alert routing and notification

### Blockchain Monitoring
- Validator node health and performance
- Network latency and throughput
- Smart contract execution metrics
- Security event monitoring

### Application Monitoring
- Application performance monitoring (APM)
- Error tracking and logging
- User experience monitoring
- Business metrics tracking

## Disaster Recovery

### Backup Strategy
- Blockchain state replicated across 3+ core datacenters
- Application data multi-region replication
- Continuous replication + daily snapshots
- 7-year retention for compliance

### Failover Procedures
- Automatic failover for regional datacenters
- Manual failover for core datacenters with governance approval
- RTO: < 4 hours for core, < 1 hour for regional
- RPO: < 15 minutes

### Geographic Redundancy
- Core datacenters: Minimum 3 active, 2 standby
- Regional datacenters: N+1 redundancy per region
- Edge sites: Automatic failover to adjacent sites

## Compliance and Governance

### Regulatory Compliance
- Data residency requirements
- GDPR, CCPA privacy compliance
- SOX financial compliance
- HIPAA, PCI-DSS where applicable
- Regional regulatory compliance

### Blockchain Governance
- Multi-party governance board
- Consensus-based decision making
- Formal upgrade process
- On-chain and off-chain dispute resolution

## Scalability

### Horizontal Scaling
- Add new datacenters as needed
- Scale blockchain network with new validators
- Expand edge sites for coverage
- Scale storage and compute independently

### Vertical Scaling
- Upgrade hardware in existing datacenters
- Increase capacity of existing infrastructure
- Optimize performance through tuning

### Auto-Scaling
- Kubernetes auto-scaling for workloads
- Storage auto-scaling based on demand
- Network bandwidth scaling
- Blockchain read replica scaling

## Performance Targets

### Latency
- Edge to user: < 10ms
- Regional to user: < 50ms
- Core to user: < 100ms
- Blockchain query: < 200ms (from read replica)

### Throughput
- Blockchain transactions: 1000+ TPS
- API requests: 100K+ RPS per region
- Storage IOPS: 100K+ per datacenter
- Network bandwidth: 100Gbps+ between core datacenters

### Availability
- Core datacenters: 99.99% uptime
- Regional datacenters: 99.9% uptime
- Edge sites: 99.5% uptime
- Blockchain network: 99.99% uptime

## Technology Stack Summary

### Blockchain
- **Platform**: Hyperledger Besu (recommended) or Quorum
- **Smart Contracts**: Solidity
- **Development**: Hardhat/Truffle
- **Integration**: Web3.js/Ethers.js

### Infrastructure
- **Orchestration**: Kubernetes
- **IaC**: Crossplane, Terraform
- **GitOps**: ArgoCD
- **Monitoring**: Prometheus, Grafana, Loki

### Storage
- **Distributed**: Ceph
- **Local**: ZFS
- **Object**: MinIO
- **Blockchain**: LevelDB/RocksDB

### Networking
- **Zero Trust**: Cloudflare
- **Tunnels**: Cloudflare Tunnels
- **Load Balancing**: Cloudflare + internal load balancers

### Identity
- **IAM**: Keycloak, OkraID
- **Blockchain Identity**: Smart contracts
- **SSI**: Self-sovereign identity support

## Related Documentation

- [Datacenter Architecture](./datacenter_architecture.md) - Detailed datacenter specifications
- [Blockchain EEA Architecture](./blockchain_eea_architecture.md) - Detailed blockchain architecture
- [Deployment Plan](./deployment_plan.md) - Deployment procedures
- [Hardware BOM](./hardware_bom.md) - Hardware specifications
- [Architecture Diagrams](../architecture/README.md) - Visual architecture diagrams
