Caller ID Attestation
Advanced caller ID authentication system with multi-level attestation, verification tokens, and cryptographic signing.
Caller ID Authentication Framework
Caller ID Attestation is the foundation of modern call authentication. It verifies that the calling party number displayed to the called party is legitimate and authorized, preventing spoofing and fraud at the network level.
What is Attestation?
Attestation is a cryptographic verification that confirms the calling party number is legitimate. Each call carries a digital signature proving the calling number's authenticity.
- • Cryptographic verification of caller identity
- • Multi-level authentication confidence
- • Real-time signature validation
- • Call routing based on trust levels
Authentication Levels
Different levels of confidence in caller authenticity, from full verification to gateway attestation.
- • Level A: Full attestation (highest confidence)
- • Level B: Partial attestation (intermediate)
- • Level C: Gateway attestation (lowest)
- • Unverified: No attestation available
Why Caller ID Attestation Matters
Caller ID attestation addresses the fundamental vulnerability in today's telecommunications network: the lack of caller identity verification.
- Prevents caller ID spoofing and fraud
- Protects customers from fraudulent calls
- Enables intelligent call routing decisions
- Supports FCC regulatory requirements
Technical Implementation
Verification Tokens
Verification tokens are JWT (JSON Web Tokens) that cryptographically assert the calling party number's authenticity.
"header": { "alg": "RS256" },
"payload": {
"iss": "originating-carrier",
"sub": "+1-555-0123",
"attest": "A",
"iat": 1234567890
}
}
Cryptographic Signing
Each verification token is cryptographically signed using RSA-256, proving it came from the originating carrier.
- • Algorithm: RS256 (RSA Signature with SHA-256)
- • Key Size: 2048-bit RSA private/public key pair
- • Certificate Authority: FCC-approved CA issues certificates
- • Signature Verification: Terminating carrier validates with carrier's public key
Call Flow with Attestation
Call Origination
Originating carrier receives call from customer
Token Generation
Generate verification token with caller number and attestation level
Cryptographic Signing
Sign token with originating carrier's private key
SIP Transmission
Attach signed token to SIP Identity header in call message
Validation
Terminating carrier validates signature using originating carrier's public certificate
Routing Decision
Route call or apply policies based on attestation level and validation result
Attestation Level Decisions
Level A (Full Attestation): Originating carrier has direct relationship with caller and has verified their identity. Allow call, display caller number with confidence.
Level B (Partial Attestation): Originating carrier has partial knowledge but cannot fully verify. Display caller number but may apply additional screening.
Level C (Gateway Attestation): Call came through intermediate gateway. Display caller number with warning or apply stricter filtering.
Unverified: No attestation available or validation failed. May block, flag for review, or apply aggressive filtering.
Benefits of Caller ID Attestation
For Carriers
- • Reduce fraud and abuse on network
- • Improve customer trust and satisfaction
- • Meet FCC regulatory requirements
- • Make intelligent routing decisions
- • Reduce support costs from fraud
For Customers
- • Know who is actually calling
- • Prevent spoofed caller ID fraud
- • Reduce unwanted robocalls
- • Increased security and privacy
- • Better trust in caller identity