Reference Architecture Diagram + Narrative (SIP/SBC mesh, numbering, E911/NG911, STIR/SHAKEN)
┌───────────────────────────────────────────────┐
│ CALL DOMAINS │
CCaaS/UCaaS Clouds │ Contact Hubs │ WFH Agents │ Branches │ PSAP/NG911 │
└───────────────┬─────────┬──────────┬───────────┘
│ │ │
▼ ▼ ▼
┌─────────────────────────────────────────────────────────────────┐
│ GLOBAL SIP / SBC MESH (CORE) │
│ • Any-to-any SIP interop • Topology hiding • Media anchoring │
│ • STIR/SHAKEN attestation • SRTP/TLS • Codec policy (OPUS/G.711)
│ • CAC/Rate controls • Fraud analytics • ENUM/DNS failover │
└───────────────┬───────────────────────────────┬─────────────────┘
│ │
▼ ▼
┌──────────────────────────────────┐ ┌──────────────────────────────────┐
│ NUMBERING & POLICY SERVICES │ │ E911/NG911 & LOCATION SERVICES │
│ • Global DIDs/TFNs (per country)│ │ • LIS/HELD/HELD+ │
│ • Porting (LNP), CNAM, RCF │ │ • ALI/ESRP/ESInet (NENA i3) │
│ • Regional PSTN compliance │ │ • Geo-pin, civic address maps │
└───────────────┬──────────────────┘ └───────────────┬──────────────────┘
│ │
▼ ▼
┌──────────────────────────────────┐ ┌──────────────────────────────────┐
│ CARRIER EDGE & PSTN GATEWAYS │ │ RECORDING / COMPLIANCE VAULT │
│ • Multi-carrier trunks │ │ • WORM storage • Retention/holds│
│ • Local-law intercept support │ │ • Redaction, KMS, access audit │
└───────────────┬──────────────────┘ └──────────────────────────────────┘
│
▼
┌────────────────────────────────────────────────────────────────┐
│ SECURITY / GOVERNANCE FABRIC (SASE/SSE + IdP/PAM + GRC) │
│ • ZTNA for admins • PAM/JIT (SBC access) • SIEM/SOAR (UEBA) │
│ • DLP on transcripts • Policy-as-code per country/sector │
│ • STIR/SHAKEN cert mgmt (HSM/KMS/PKI) │
└────────────────────────────────────────────────────────────────┘
Observability/QoE bus ──► AIOps (MOS, ASR/NER, jitter, fraud) • ITSM/CMDB • Regulatory dashboards
Narrative (how global telephony stays lawful, high-quality, and fraud-resistant)
1) Purpose & posture
- Objective: Provide a single, worldwide voice and numbering fabric that connects CCaaS/UCaaS, hubs, branches, WFH agents, and public-safety endpoints to local PSTNs with lawful compliance and consistent QoE.
- Posture: Zero-trust admin, crypto-anchored identity (STIR/SHAKEN), regional policy enforcement, and evidence-ready recording/retention.
2) SIP/SBC core (syntax of call control)
- Global SBC mesh terminates all SIP; performs topology hiding, media anchoring, transcoding policy, SRTP/TLS.
- STIR/SHAKEN attestation and verification prevent spoofing; ENUM/DNS gives resilient number routing; rate/CAC protect against bursts and toll fraud.
3) Numbering & policy (semantics by jurisdiction)
- DIDs/TFNs issued per country with correct regulatory attributes; LNP workflows automate porting.
- CNAM, robocall filtering, robocall mitigation policies per region.
- Policy-as-code tags every number/trunk with country, sector (PCI/HIPAA/CJIS), retention, redaction rules.
4) Emergency services (meaning under duress)
- LIS/HELD/HELD+ resolve location for nomadic endpoints; NENA i3 interop to ESInet/NGCS.
- Geo-pin rules ensure calls exit via the correct local gateway with correct civic address and PSAP mapping.
5) Carrier edge & PSTN gateways
- Multi-carrier interconnects per region for cost/latency diversity and local-law conformance (e.g., CLI presentation, lawful intercept).
- BGP + SD-WAN steering to healthy trunks; media relocation to nearest edge for lower jitter.
6) Recording, redaction & evidence
- WORM/immutable recording vault with key custody (HSM/KMS); PII/PHI redaction pipelines; access-logged retrieval by role and jurisdiction.
- Supports sectoral retention (PCI voice scope, HIPAA telehealth, public-safety archives).
7) Security & governance
- Admin access via ZTNA + PAM/JIT (every SBC change recorded).
- SIEM/SOAR correlates fraud spikes, call floods, quality anomalies; playbooks can reroute, block ranges, rotate STIR certs, open ITSM.
- GRC dashboards prove compliance (GDPR/CCPA, telecom acts, E911/NG911, lawful intercept readiness).
8) Resilience patterns
- Active/active SBC POPs with sub-30s reroute; multi-carrier failover; codec fallback when bandwidth degrades.
- WFH agent path protection: DIA→LTE media failover; AIOps raises MOS-driven path changes.
9) Reference KPIs
- POP/SBC availability: ≥99.999%
- Call setup time (PSTN): <2 s median
- MOS (global voice): ≥4.0 median
- Failover (trunk/POP): <30 s without active-call drop (where supported)
- Fraud containment MTTR: ≤30 min
- Regulatory conformance incidents: 0 critical
10) Minimal BOM (mapped to earlier matrix)
Global SBC mesh, Multi-carrier SIP trunks, Numbering (DID/TFN) & LNP services, STIR/SHAKEN PKI (HSM/KMS/CA), E911/NG911 (LIS/ESInet/NGCS), Recording/WORM vault with redaction/KMS, SASE/SSE (ZTNA/SWG/CASB/FWaaS/DLP), SIEM/SOAR + Fraud analytics, AIOps QoE, ITSM/CMDB, Policy-as-code engine.