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Full E2E Interconnect Certification Plan

SIG-GW / IBCF — Carrier Interconnect Readiness

Author: Daniel
Scope: End-to-end NNI/Ic validation before peering activation


1. Certification Phases

Phase 1: Lab Functional Validation

Duration: 1-2 weeks
Environment: Isolated lab environment
Objective: Validate all functional requirements

Phase 2: Controlled Interconnect Testing

Duration: 1 week
Environment: Controlled interconnect with partner
Objective: Validate interconnect scenarios

Phase 3: Load & Soak Testing

Duration: 1 week
Environment: Production-like load
Objective: Validate performance and stability

Phase 4: Regulatory Scenario Validation

Duration: 1 week
Environment: Production-like with regulatory scenarios
Objective: Validate regulatory compliance

Phase 5: Operational Readiness

Duration: 1 week
Environment: Production
Objective: Validate operational procedures


2. Functional Validation

2.1 Basic SIP Call Flows

Test Cases: - INVITE → 100 Trying → 180 Ringing → 200 OK → ACK - BYE → 200 OK - CANCEL → 487 Request Terminated → 200 OK - Re-INVITE (mid-call update) - UPDATE (early media)

Acceptance Criteria: - All call flows complete successfully - Response codes correct - Headers properly formatted - Timers respected

2.2 Topology Hiding Verification

Test Cases: - Internal Via headers removed - Internal Record-Route headers removed - Contact headers rewritten - SDP connection addresses hidden

Acceptance Criteria: - No internal IPs exposed - No internal hostnames exposed - Topology completely hidden

2.3 Codec Negotiation Compliance

Test Cases: - AMR-WB negotiation - G.711 negotiation - H.264 negotiation (video) - Codec mismatch handling - Transcoding (if enabled)

Acceptance Criteria: - Codecs negotiated correctly - Fallback works - SDP properly formatted

2.4 STIR/SHAKEN Signing & Verification

Test Cases: - A-level attestation signing - B-level attestation signing - C-level attestation signing - Signature verification - Certificate chain validation - OCSP validation

Acceptance Criteria: - All calls signed correctly - Signatures verify correctly - Attestation levels correct - Certificates valid

2.5 Emergency Routing Validation

Test Cases: - 911 routing (US) - 112 routing (EU) - 999 routing (UK) - 000 routing (AU) - Location header preservation - Priority handling

Acceptance Criteria: - All emergency numbers routed correctly - Location preserved - Highest priority - No blocking

2.6 Lawful Intercept Continuity

Test Cases: - Signaling interception - Media interception - Intercept during re-INVITE - Intercept during transfer - Intercept during failover

Acceptance Criteria: - All intercepts complete - No loss during events - Audit logs complete


3. Interconnect Scenarios

Scenario Test ID Expected Result Validation
Inbound Call INT-001 Proper routing + verification Call completes, STIR verified
Outbound Call INT-002 Correct signing Identity header present, signed
Transit Call INT-003 Header preservation Identity header preserved
Emergency Call LIE-101 Priority route Routed to PSAP, no blocking
Intercepted Call LIE-001 Media duplication Signaling + media to MD
Cross-Border Call INT-004 C-level attestation Correct attestation level
Roaming Emergency LIE-110 Correct routing Routed to home PSAP
Multi-Hop Call INT-005 Header integrity Identity header preserved

4. Negative & Abuse Testing

4.1 SIP Fuzzing

Test Cases: - Malformed INVITE - Oversized headers - Invalid SIP version - Missing required headers - Invalid URI formats

Acceptance Criteria: - No crashes - Proper error responses (400/488) - Logging of attacks - Rate limiting active

4.2 TLS Mismatch

Test Cases: - Invalid certificate - Expired certificate - Wrong CA - Weak cipher suite - TLS version mismatch

Acceptance Criteria: - Connection rejected - Proper error logging - No fallback to insecure

4.3 Invalid Certificates

Test Cases: - Revoked certificate - Expired certificate - Self-signed certificate - Wrong domain certificate

Acceptance Criteria: - STIR verification fails - Calls rejected (hard-fail) or marked unverified (soft-fail) - Proper logging

4.4 Attestation Spoof Attempts

Test Cases: - Attempt to upgrade A→B - Attempt to upgrade B→A - Invalid attestation claim - Missing attestation

Acceptance Criteria: - Attestation downgrade only - Invalid claims rejected - Proper logging

4.5 Flood Attacks

Test Cases: - INVITE flood (20k CPS) - ACK flood - BYE flood - Mixed method flood

Acceptance Criteria: - Rate limiting active - Legitimate calls pass - Attack traffic blocked - No crash or degradation

4.6 Malformed SDP

Test Cases: - Invalid SDP format - Missing required fields - Invalid codec names - Oversized SDP

Acceptance Criteria: - Proper error responses (488) - No crashes - Logging of errors


5. Load & Soak Testing

5.1 Burst Load Test

Test Configuration: - Load: 2× rated CPS for 60 minutes - Duration: 60 minutes - Metrics: CPS, PDD, CPU, Memory

Acceptance Criteria: - No packet loss - PDD within target - CPU < 85% - No crashes

5.2 Sustained Load Test

Test Configuration: - Load: 100% rated CPS - Duration: 24 hours - Metrics: All KPIs

Acceptance Criteria: - All KPIs within target - No memory leaks - No degradation - Stable performance

5.3 Packet Loss Simulation

Test Configuration: - Load: 100% rated CPS - Packet Loss: 10% - Duration: 1 hour - Metrics: Retransmission rate, call success

Acceptance Criteria: - Retransmissions handled - Calls complete successfully - No crashes - Graceful degradation

5.4 Certificate Rotation During Load

Test Configuration: - Load: 100% rated CPS - Event: Certificate rotation - Duration: Rotation window - Metrics: Call success, latency

Acceptance Criteria: - Zero downtime - No call drops - Latency within target - Seamless transition


6. Failover Testing

6.1 Kill Active Node

Test Configuration: - Setup: Active/Active (2 nodes) - Event: Kill primary instance - Load: 100% rated CPS - Metrics: Failover time, call loss

Expected Result: - Failover ≤ 1 second - Zero call loss - No emergency drop - No LI drop - No system crash

6.2 Restart Signaling Pod

Test Configuration: - Setup: Kubernetes pod restart - Event: Restart signaling pod - Load: 100% rated CPS - Metrics: Restart time, call handling

Expected Result: - Restart ≤ 10 seconds - In-flight calls handled - New calls accepted - No degradation

6.3 DNS Failover Test

Test Configuration: - Setup: DNS-based failover - Event: Primary DNS failure - Load: 100% rated CPS - Metrics: Failover time, DNS resolution

Expected Result: - Failover ≤ 2 seconds - DNS resolution continues - No call loss - Seamless transition

6.4 State Store Outage

Test Configuration: - Setup: State store dependency - Event: State store unavailable - Load: 100% rated CPS - Metrics: Degradation, recovery

Expected Result: - Graceful degradation - Stateless paths continue - Fast recovery (≤ 5 seconds) - No crash


7. Documentation Required

7.1 SIP Traces

Required: - Sample INVITE flow - Sample emergency call flow - Sample intercepted call flow - Sample STIR signing/verification flow - Sample failover flow

Format: PCAP or SIP message logs

7.2 KPI Dashboard Snapshots

Required: - 24-hour KPI dashboard - Peak load snapshot - Failover event snapshot - Emergency call metrics - LI intercept metrics

Format: Grafana dashboard exports

7.3 Certificate Validation Logs

Required: - Certificate fetch logs - OCSP validation logs - Certificate rotation logs - STIR signing logs

Format: Structured logs (JSON)

7.4 Audit Log Extracts

Required: - LI warrant activation logs - LI intercept logs - Emergency call logs - Security event logs

Format: Tamper-evident logs

7.5 Chaos Injection Reports

Required: - Pod kill test results - Network partition results - CPU throttling results - DNS failure results

Format: Test execution reports


8. Certification Exit Criteria

8.1 Test Execution

  • ✅ All test cases pass
  • ✅ All test catalogs executed (IBCF, STIR/SHAKEN, LI/Emergency)
  • ✅ All PIXIT configurations validated
  • ✅ All negative tests pass

8.2 KPI Targets

  • ✅ All KPIs within target
  • ✅ 72-hour sustained load test passed
  • ✅ No severity-1 incidents
  • ✅ SLO compliance validated

8.3 Regulatory Audit

  • ✅ LI compliance validated
  • ✅ Emergency compliance validated
  • ✅ STIR/SHAKEN compliance validated
  • ✅ Security compliance validated
  • ✅ Documentation complete

8.4 Peering Partner Approval

  • ✅ Interconnect scenarios validated
  • ✅ Partner test cases pass
  • ✅ Peering agreement signed
  • ✅ Production activation approved

9. Certification Timeline

Phase Duration Dependencies Deliverables
Phase 1: Lab Functional 1-2 weeks Test environment ready Functional test report
Phase 2: Controlled Interconnect 1 week Partner coordination Interconnect test report
Phase 3: Load & Soak 1 week Load test environment Performance test report
Phase 4: Regulatory 1 week Regulatory scenarios Compliance report
Phase 5: Operational Readiness 1 week Production environment Operational readiness report

Total Duration: 5-7 weeks


10. Risk Mitigation

10.1 Test Failures

  • Mitigation: Immediate investigation and fix
  • Escalation: Block certification until resolved
  • Documentation: Failure analysis and resolution

10.2 Partner Delays

  • Mitigation: Early coordination and scheduling
  • Contingency: Extended timeline
  • Communication: Regular status updates

10.3 Regulatory Changes

  • Mitigation: Stay current with regulations
  • Updates: Adapt test scenarios
  • Documentation: Update compliance checklist

End of Interconnect Certification Plan