Digital Lending Modernization

1. Layered Text Architecture Diagram

(Persona → API → Microservices → Data → Hybrid → SEBI)

[ Personas ]

Investor (Loan Applicant)

Distributor (Bulk Loan Initiator)

Operations (Compliance & Monitoring)

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v

[ Presentation & API Layer ]

- Angular Loan Portal (Public Subnet, Azure CDN + Front Door)

- API Management (APIM) – OAuth2/JWT, throttling, versioning

- Azure AD B2C (Investor) / Azure AD MFA (Ops & Distributor)

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v

[ Microservices Layer (AKS + Istio) ]

- Loan Origination MS (Create Loan, Capture Details)

- KYC MS (Real-time KYC via RTA API, fallback batch via ADF)

- Credit Scoring MS (Credit bureau integration via APIM)

- Loan Evaluation MS (Eligibility rules, risk scoring)

- Agreement MS (DocuSign, PDF generation, archival)

- Disbursement MS (Payment gateway integration)

- Notification MS (Email/SMS updates via Event Grid/SendGrid)

- Compliance MS (SEBI/RBI reporting, data export to ADF)

- Reconciliation MS (Cloud vs Legacy sync checks)

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v

[ Data Layer ]

- Azure SQL Managed Instance (System of Record)

- Cosmos DB (Real-time loan portfolio, multi-region writes)

- Redis Cache (Session + hot data caching)

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v

[ Hybrid Integration Layer ]

- ExpressRoute / VPN Gateway (Private connectivity to legacy loan system)

- Linked Servers / CDC (SQL MI ↔ On-prem SQL)

- Azure Data Factory (Nightly batch sync + RTA/credit fallback)

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v

[ Compliance & SEBI Layer ]

- Compliance MS → ADF pipelines → SEBI SFTP/REST endpoints

- Blob Storage WORM (Immutable storage for 7+ years)

- Log Analytics (Audit trail for compliance events)

2. Microservices Mapping with DDD Responsibilities & Azure Components

Domain-Driven Design (DDD) Bounded Contexts:

Loan Origination Microservice

• Responsibilities:

  • Create loan application

  • Capture borrower details & documents

  • Validate basic eligibility

• Azure Components:

  • AKS (Java Spring Boot service)

  • APIM (expose REST APIs)

  • Azure SQL MI (persist applications)

  • Service Bus Topic (loan_created event)

KYC Microservice

• Responsibilities:

  • Integrate with RTA APIs for KYC validation

  • Fallback batch KYC via ADF (SFTP files)

• Azure Components:

  • AKS (service) + APIM (API security)

  • ADF (batch pipeline)

  • Key Vault (store API keys for RTA)

  • Service Bus Topic (kyc_completed event)

Credit Scoring Microservice

• Responsibilities:

  • Fetch credit score from bureaus (CIBIL/Experian)

  • Apply credit models for risk assessment

• Azure Components:

  • AKS + APIM

  • Service Bus eventing

  • SQL MI (store credit score)

Loan Evaluation Microservice

• Responsibilities:

  • Aggregate KYC + credit score + legacy exposure

  • Compute final loan eligibility & approval

• Azure Components:

  • AKS (Java microservice)

  • Linked Server (read legacy exposure)

  • SQL MI (store decision)

Agreement Microservice

• Responsibilities:

  • Generate loan agreement (PDF)

  • Integrate with DocuSign for e-signature

  • Archive signed agreements

• Azure Components:

  • Blob Storage (PDF archival, WORM mode)

  • APIM (DocuSign API)

Disbursement Microservice

• Responsibilities:

  • Call payment gateway / core banking API

  • Update disbursement status in SQL MI & legacy

• Azure Components:

  • AKS + APIM

  • SQL MI (transaction log)

  • Service Bus (loan_disbursed event)

Notification Microservice

• Responsibilities:

  • Send SMS/email notifications for status updates

• Azure Components:

  • Event Grid (trigger notifications)

  • SendGrid (email) / Twilio (SMS)

Compliance Microservice

• Responsibilities:

  • Generate SEBI/RBI compliance reports (loan portfolios, NPAs)

  • Trigger exports via ADF pipelines

• Azure Components:

  • AKS service

  • ADF (report delivery to SEBI endpoint)

  • Blob WORM (immutable archive)

Reconciliation Microservice

• Responsibilities:

  • Compare cloud SQL MI vs legacy SQL

  • Flag mismatches for Ops review

• Azure Components:

  • AKS

  • Linked Server + ADF (data sync)

  • Log Analytics (discrepancy logging)

3. Combined Text Version Sequence Diagram

(Loan Application → Disbursement with Hybrid + SEBI touchpoints)

Investor → Angular App → APIM → Loan Origination MS

| (JWT Auth via Azure AD B2C)

| Save to SQL MI, Emit `loan_created` event → Service Bus

|

KYC MS (Subscribes) → Call RTA API via APIM

| (If fail → fallback ADF batch)

| Update SQL MI, Emit `kyc_completed`

Credit Scoring MS (Triggered) → Call Credit Bureau via APIM

| Update SQL MI, Emit `credit_score_ready`

Loan Evaluation MS (Triggered) → Fetch data:

| - SQL MI (Loan & credit data)

| - Linked Server (Legacy exposure)

| Compute eligibility → Update SQL MI, Emit `loan_decision_made`

Agreement MS → Generate agreement (Blob WORM) → DocuSign API (APIM)

| Emit `agreement_signed`

Disbursement MS → Call Payment Gateway via APIM

| Update SQL MI + Legacy via Linked Server

| Emit `loan_disbursed` event

Notification MS → Send SMS/Email (Event Grid → SendGrid/Twilio)

Compliance MS (Scheduled) → Generate SEBI report

| ADF pipeline → SEBI endpoint (SFTP/REST)

| Archive report to Blob WORM

| Log event to Log Analytics (audit trail)

Ops Dashboard → Real-time view (Cosmos DB) + Reconciliation (Legacy vs Cloud)

4. Risk Matrix (Top 20 Risks)

#	Risk Category	Risk Description	Impact	Mitigation
1	Business	Data inconsistency cloud vs legacy	Wrong loan decisions	Dual-write + CDC + reconciliation dashboards
2	Business	Delayed compliance reporting	Regulatory penalties	Automated ADF pipelines, Blob WORM archive
3	Technology	Latency in hybrid connectivity	Slower loan approvals	ExpressRoute, Redis cache legacy data
4	Technology	Event Bus overload	Message loss	Service Bus partitioning, DLQs, autoscaling
5	Technology	SQL MI performance degradation	Slower queries	Index tuning, elastic pools, query store
6	Technology	Cosmos DB RU throttling	API failures	Autoscale RUs, partitioning strategy
7	Technology	AKS node failure	Service downtime	Node pools + autoscaler, multi-region setup
8	Security	PII data leakage	Regulatory breach	TDE, Always Encrypted, Key Vault secrets
9	Security	API DDoS attack	Service outage	APIM rate limiting, Front Door WAF
10	Security	Unauthorized hybrid access	Data breach	Private Endpoints, NSGs, RBAC
11	Compliance	Failure to meet SEBI retention	Legal non-compliance	Blob WORM, Azure Policy enforcement
12	Compliance	Missing audit trails	Audit failures	Log Analytics central logging
13	Operational	Deployment misconfigurations	Production outages	Blue-green/canary deployments via Istio
14	Operational	Monitoring blind spots	Delayed incident response	Unified Azure Monitor dashboards
15	Operational	Skill gaps in cloud adoption	Delivery delays	Training, paired ops, runbooks
16	Operational	Cost overruns	Budget breaches	FinOps, autoscale policies, reserved instances
17	DR/HA	Region-wide failure	Platform outage	Traffic Manager failover, multi-region DB
18	DR/HA	Data loss in failover	Financial loss	Cosmos multi-write, SQL MI failover groups
19	Integration	Credit bureau/RTA API downtime	Loan approval delays	Circuit breaker + ADF batch fallback
20	Performance	High traffic spikes	SLA violations	AKS autoscale, Redis hot caching, Cosmos scale-out