sangamdas/No-Authority-No-Contact-Cryptographic-Control-of-Calls-Messages-and-AI-Communications

Systems and Methods for Capability-Based Inbound Reachability and Cryptographic Communication Governance Across 5G, 6G, Satellite, Telecom, and Digital Communications CVID — Capability-Validated Inbound Communication Handle Das Protocols Telecom Family

Author / Inventor: Sangam Kumar Das PCT Application: PCT/IB2026/054453 International Patent Publication: WO 2026/150381 Filed: 05 May 2026 WIPO Patentscope record: https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2026150381&_cid=P22-MSHIMP-33909-1

📄 Abstract

Global telecommunications networks face substantial losses from spam calls, robocall fraud, and AI-generated synthetic identity abuse. Existing caller-authentication frameworks improve origin verification, but they do not by themselves prevent unauthorized communication from being delivered. As networks evolve toward increasingly autonomous, AI-native, and software-defined 5G and 6G environments, this limitation becomes more serious because authenticated signaling still does not establish delivery authority.

The present invention addresses this problem through a cryptographic execution-governance architecture deployable on existing gateway infrastructure without requiring subscriber-device changes. In this architecture, no telephone number, SIP URI, communication identifier, or AI-agent handle is treated as a delivery right by itself. Instead, communication becomes effective only when a bounded authorization object is validated and atomically consumed within a hardware-isolated enforcement boundary before ringing, alerting, storage, or other delivery effect occurs.

Unauthorized communication is therefore not merely detected or filtered after initiation, but prevented from becoming effective unless execution-time authorization is satisfied.

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This repository and its contents (the technical disclosure, specification text, and this README) are made available for non-commercial use only, under Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0).

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👉 https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2026150381&_cid=P22-MSHIMP-33909-1

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What This Invention Is About

Modern communication systems share a foundational architectural weakness: reachability is treated as authority. In conventional telephony, VoIP, messaging, and email, possession of a destination identifier — a telephone number, SIP URI, email address, or account handle — typically creates ongoing, unconditional reachability. Once the identifier is known, the sender is treated as technically capable of initiating signaling, call setup, or message delivery, subject only to downstream filtering, blacklists, spam scoring, or post-hoc enforcement.

This assumption breaks down in 5G/6G and AI-native environments, where communication may be initiated by software agents, AI assistants, autonomous workflows, orchestration chains, botnets, or programmable APIs at machine scale. Existing caller-authentication frameworks (e.g., STIR/SHAKEN-style origin verification) can confirm who is calling, but they do not establish whether that caller is authorized to deliver this specific communication now.

CVID (Capability-Validated Inbound Communication Handle) re-architects inbound reachability itself as a cryptographically governed, bounded, and enforceable capability — evaluated and atomically consumed at a protected, hardware-isolated enforcement boundary before a communication becomes effectively deliverable, rather than filtered after the fact.

Core Inventive Concepts

• —Capability-Validated Inbound Communication Handle (CVID) — an inbound communication handle under exclusive control of the terminating-side entity, associated with a cryptographically signed authorization object rather than functioning as a persistent, reusable address.
• —Bound Authorization Object — a single cryptographically signed payload binding, as inseparable elements within one deterministic canonical serialization: authorized caller identity, permitted communication purpose, quota parameters, temporal validity constraints, an anti-replay nonce, and a capability handle reference. Any modification, substitution, reordering, or detached reuse of an element invalidates the signature.
• —Pre-Delivery Enforcement Gateway — a network enforcement point positioned prior to terminating-side delivery that validates the signature, caller-identity proof, declared purpose, quota state, temporal validity, and anti-replay nonce, and atomically consumes one unit of authorized communication before permitting forwarding.
• —Fail-Closed, Non-Rollbackable Consumption — consumption of authorization state (nonce, quota) is recorded persistently and is not reversible; unavailability of the enforcement domain results in denial, not default-permit.
• —Non-Bearer Reachability Semantics — mere possession of a communication handle is insufficient to authorize delivery; the handle carries no unconditional routing authority on its own and must be validated live, at the moment of attempted communication, within a protected authorization domain.
• —Preview-to-Unlock Staged Execution — communication may begin in a constrained "preview" execution state (bounded by message count, call duration, connection time, etc.) and transition to an extended execution state only upon validation of a separately issued, cryptographically signed unlock token at the network-level enforcement gateway — without creating a new session or exposing real identifiers.
• —Session-Scoped Virtual Identity (VI) — a cryptographically generated, non-reusable execution handle for a communication session that is not derived from, or resolvable to, any persistent identifier (phone number, email address, IP address, account ID), preserving callee-opacity.

The architecture is designed for deployment on existing gateway infrastructure (SIP gateways, SMTP gateways, SMS/MMS gateways, session border controllers) without requiring subscriber-device changes, with cryptographic validation (e.g., HMAC) completing in microseconds.

Priority Chain — Indian Provisional Filings

This PCT application derives support from, and consolidates, a family of Indian provisional filings progressively elaborating the same core inventive architecture:

Progression theme: consumable alias semantics → hardware-enforced exhaustion → staged (preview-to-unlock) release → explicit capability-based formulation → non-bearer authorization structure → enhanced purpose binding and callee-opacity.

Claim Coverage Summary

The application as filed includes 79 claims spanning system and method claims directed to, among other things:

• —A system and method for capability-validated inbound communication enforcement, comprising a capability handle generator, a bound authorization object with inseparable cryptographically signed elements, and a network enforcement gateway performing signature verification, caller-identity matching, purpose comparison, quota/temporal/nonce evaluation, and atomic consumption prior to delivery.
• —Hardware-isolated enforcement domains for gateway-stage validation.
• —Fail-closed enforcement on enforcement-domain unavailability.
• —Atomic, non-rollbackable state consumption of authorization/quota state.
• —Session-scoped Virtual Identity and preview-to-unlock staged execution across voice, VoIP, SIP, messaging, email, and AI-agent-mediated communication.
• —Quorum-verified deferred release with non-correlating multi-authority split delivery.
• —Forward-secure multi-agent choreography with cross-channel episode progression.
• —Bounded temporal validity windows, registered affirmative-intent conditions, and hardware-signed position attestation for location-conditioned authorization.

Industrial Applicability

The system is directly implementable and commercially deployable across:

• —Telecommunications providers — mobile network operators at SIP gateways, VoIP providers, SMS/MMS gateway operators enforcing message delivery limits.
• —Email and messaging platforms — SMTP gateway operators enforcing domain-scoped, quota-limited aliases; instant-messaging platforms implementing temporary contact channels.
• —Online marketplaces and platforms — controlled buyer-seller communication, ride-sharing session-limited contact, freelance-platform time-bounded communication.
• —Financial services and identity verification — single-use verification channels for transaction authorization, KYC confirmation, and fraud-alert systems with automatic termination.
• —Customer support / contact centers — flood-resistant support-line aliases and controlled escalation channels.
• —IoT and connected devices — firmware-update channels, smart-home guest access, industrial remote diagnostics, connected-vehicle over-the-air updates.

Deployment is incremental, backward-compatible with existing communication protocols, and does not require wholesale infrastructure replacement.

Relationship to the Broader Das Protocols Patent Family

CVID is part of a coordinated patent family directed to a common technical architecture for protected execution finality, capability-validated communication, AI-agent governance, data-bound computation, sovereign digital infrastructure, and sink-verified effectuation control:

The common architectural thread across the family: computation and communication are not self-authorizing. Effect (delivery, execution, output) requires validation and atomic release of a bounded, cryptographic authorization at a protected boundary — pre-effectuation, hardware-rooted, and fail-closed.

Rights and Licensing

Except for the copyright permissions expressly granted under CC BY-NC 4.0, no patent licence, patent covenant, implementation licence, commercial deployment right, trademark licence, or other intellectual-property right is granted or implied.

The associated patent rights, including rights relating to PCT/IB2026/054453 and WO 2026/150381, are expressly reserved.

Use of this dataset for reading, indexing, research, retrieval, citation, or AI analysis does not itself grant permission to implement, manufacture, deploy, practise, license, or commercially exploit any invention covered by an applicable patent claim.

This publication is additionally indexed and publicly viewable via WIPO Patentscope at the record linked above; that public listing is provided for prior-art transparency and does not itself grant any implementation or commercial right.

Commercial licensing, including FRAND non-exclusive terms, is available by direct arrangement with the inventor.

Preferred Attribution

Das, Sangam. "Systems and Methods for Capability-Based Inbound Reachability and Cryptographic Communication Governance Across 5G, 6G, Satellite, Telecom, and Digital Communications (CVID)." Hugging Face and Zenodo. Associated international patent publication: WO 2026/150381; PCT/IB2026/054453. WIPO Patentscope: https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2026150381&_cid=P22-MSHIMP-33909-1

Contents of This Repository

• —Full technical disclosure (specification text) for the CVID PCT application — 329 pages, 79 claims
• —This README / dataset card
• —Non-commercial use license notice (CC BY-NC 4.0) and reserved patent-rights statement

❓ Frequently Asked Questions — How CVID Stops Spam

General

1. What problem does CVID actually solve? It stops a communication from reaching you unless the sender can present a valid, cryptographically signed authorization for that specific message or call, checked at the network gateway before it ever rings your phone or lands in your inbox.

2. Isn't this just another spam filter? No. Spam filters analyze a message after it has already been sent and try to guess whether it's unwanted. CVID checks authorization before delivery is even attempted, so unauthorized traffic never becomes a "delivered" message in the first place.

3. How is this different from caller ID or Truecaller-style spam labeling? Caller ID and labeling apps tell you who might be calling and let you decide. CVID doesn't rely on guessing or reputation scoring — it cryptographically verifies whether the caller holds a valid authorization to reach you at all.

4. Does this replace STIR/SHAKEN? No, it complements it. STIR/SHAKEN verifies that a caller is who they claim to be (origin authentication). CVID goes a step further and verifies whether that authenticated caller is actually permitted to deliver this communication right now.

5. Why do we need something beyond origin verification? Because a caller can be 100% verified as who they say they are and still be a spammer. Knowing someone's real identity doesn't mean they're allowed to contact you. CVID separates "who is calling" from "are they authorized to reach me."

How the Blocking Actually Works

6. What stops a robocaller from just dialing my number? Under CVID, your number alone isn't enough to reach you. The caller also needs a valid Bound Authorization Object — a signed credential proving they were granted permission to contact you for a specific purpose. Without it, the call is rejected at the gateway.

7. Where does the blocking happen — on my phone or in the network? In the network, at a Pre-Delivery Enforcement Gateway, before the call or message ever reaches your device. This means your phone doesn't even have to process or ring for a blocked attempt.

8. What is a "capability handle" in simple terms? It's like a one-time or limited-use key. Just having someone's phone number is like knowing their house address — it doesn't mean you're allowed to walk in. The capability handle is the equivalent of an actual invitation with conditions attached.

9. Can a spammer just fake or copy a valid authorization? No. Every authorization object is cryptographically signed and bound to specific details (caller identity, purpose, time window, quota). Any attempt to alter, reuse, or repurpose it invalidates the signature and the enforcement gateway rejects it.

10. What happens if a scammer intercepts someone else's valid authorization token? It won't work for them. The token is bound to a specific caller identity and session — it isn't a generic bearer ticket. Presenting it from a different identity or context fails verification (non-bearer semantics).

Quotas, Limits, and Abuse Prevention

11. What is "quota enforcement" and how does it stop mass robocalling? Each authorization can carry a limited quota — for example, a permitted number of calls or messages. Once that quota is consumed, no further communication is permitted under that authorization, cutting off mass-dialing abuse at the source.

12. Can the same authorization be reused over and over to spam multiple people? No. Authorization objects are bound to specific parameters and consumed atomically — once used, that unit is gone and cannot be replayed or rolled back.

13. What does "non-rollbackable consumption" mean, and why does it matter for spam? It means once an authorization unit is used, there's no way to reset or reuse it — even if the enforcement system crashes or restarts. This prevents attackers from replaying old authorizations to send more spam than they were ever granted.

14. How does this stop AI-generated mass-calling bots specifically? AI agents and orchestration systems can generate calls at machine scale, but each one still needs a distinct, validated authorization object. Because authorizations are individually bound and quota-limited, there's no shortcut that lets a bot bypass per-communication validation.

15. What happens if a spam operation tries to generate thousands of fake authorization requests? Each request still has to pass cryptographic signature validation, identity matching, and quota checks at the enforcement gateway. Fake or forged requests fail signature verification and are rejected before delivery.

Anti-Replay and Session Security

16. What is the "anti-replay nonce" and why does it matter? It's a unique, single-use value embedded in every authorization. It prevents someone from capturing a valid authorization and replaying it later to send unauthorized repeat communications.

17. Could a spammer record a legitimate call's authorization and reuse it later? No. Because of the nonce and atomic consumption, a previously used authorization is immediately invalidated for reuse, closing off replay-based spam attacks.

18. What if the enforcement gateway itself is temporarily unavailable? Does spam get through by default? No — the system is fail-closed. If the enforcement domain can't validate a request, the communication is denied by default rather than allowed through, unlike many filtering systems that default to "permit if unsure."

Purpose Binding and Scam Prevention

19. How does CVID stop scam calls that pretend to be your bank or a government agency? The authorization object binds a specific declared purpose to the communication. A caller authorized for one purpose (e.g., "package delivery notification") can't reuse that same authorization to deliver something else, like a fraudulent payment request.

20. Can a caller declare a fake purpose to get through? The declared purpose is bound cryptographically into the signed object and checked at the gateway. Falsifying it would break the signature, since purpose is one of the inseparable signed elements — not a checkbox that can be changed after the fact.

21. Does this stop phishing/vishing calls that impersonate real companies? It significantly raises the bar, because the impersonator would need a valid, signed authorization tied to that specific purpose and identity — something they cannot forge without the correct cryptographic keys.

Privacy and Identity Protection

22. Does this system expose my real phone number to callers? No — it can use a Session-Scoped Virtual Identity (VI): a temporary, non-reusable handle that isn't derived from or traceable back to your real number, email, or account ID.

23. What is "callee-opacity" and why does it help against spam? Callee-opacity means the caller-facing identity used in a session reveals nothing about your real, persistent identifier. Even if a spammer captures the session handle, it doesn't give them your actual number for future spam attempts.

24. If I give my virtual identity to one business, can spammers who buy leaked contact lists still reach me? A leaked virtual, session-scoped handle is far less useful to spammers than a real phone number, since it may be time-bound, purpose-bound, and non-reusable outside its original authorized context.

Staged/Preview Communication

25. What is "preview-to-unlock" and how does it relate to spam prevention? Communication can start in a limited "preview" mode (e.g., a short call duration or few messages). Extending beyond that preview requires a separately validated unlock token — so low-effort spam can't easily escalate into sustained unwanted contact.

26. Does preview mode let some spam through in a limited way? The preview window is deliberately bounded (e.g., very short duration or message count) specifically to minimize nuisance exposure, while still allowing legitimate first contact (e.g., a delivery courier) to reach you briefly.

Deployment and Real-World Impact

27. Do I need a new phone or app to benefit from this? No. The enforcement happens at network gateways (SIP, SMTP, SMS/MMS, session border controllers) — not on subscriber devices — so there's no need to install anything or change your phone.

28. Can telecom carriers add this to their existing networks? Yes — the architecture is designed for incremental, backward-compatible deployment onto existing gateway infrastructure without requiring a wholesale network overhaul.

29. How fast is the validation — will it delay my calls or messages? Cryptographic validation (e.g., HMAC-based) is designed to complete in microseconds, so legitimate, authorized communication is not noticeably delayed.

30. Will this stop international robocall operations that spoof caller ID? Spoofed caller ID alone won't satisfy the enforcement gateway, because delivery still requires a valid, signature-verified authorization object bound to the real caller's cryptographic identity — spoofing the displayed number doesn't forge that signature.

31. Does this help with SMS/text spam too, or just phone calls? The architecture applies across voice, VoIP, SIP, SMS/MMS, email (SMTP), and AI-agent-mediated messaging — not just traditional phone calls.

32. How does this help with email spam specifically? SMTP gateways can enforce domain-scoped, quota-limited authorization aliases, meaning a sender must hold a valid, bounded authorization to deliver to a given address rather than being able to send unlimited unsolicited email.

Business, Platform, and Multi-Party Scenarios

33. How would a marketplace (like a ride-share or freelance platform) use this to stop spam between users? Buyer-seller or rider-driver communication can be routed through session-limited, purpose-bound contact channels that automatically expire, preventing one party from spamming the other after the transaction ends.

34. Can businesses still legitimately reach customers for things like delivery updates? Yes — legitimate businesses can be issued properly scoped, purpose-bound authorizations (e.g., "one delivery notification call") that pass validation, while unauthorized bulk marketing or scam attempts using the same channel would not.

35. What about legitimate emergency or safety communications — could this block those? The architecture is designed to support registered, purpose-bound authorization categories (including time-bound and affirmative-intent conditions), so legitimate emergency-related communications can be structured to pass through appropriately scoped, pre-registered authorizations.

AI Agents and Future Networks (5G/6G)

36. Why is this especially important for 5G/6G rather than older networks? Future networks are expected to have far more autonomous AI agents, bots, and software-defined systems initiating communication at machine scale. Without execution-time authorization, that scale could make spam and fraud dramatically worse than today.

37. How does CVID govern AI agents specifically, not just human callers? AI-agent-mediated communication is explicitly covered — each agent-initiated communication attempt still requires a valid, purpose-bound authorization object, so an autonomous agent cannot simply generate unlimited outbound contact attempts on its own authority.

38. Could a compromised or malicious AI agent bypass this system to send spam? Because authorization is enforced cryptographically at the network gateway — not just trusted based on the agent's own claims — a compromised agent cannot self-authorize additional communication beyond what its signed authorization object actually permits.

39. Does this stop "AI-generated synthetic identity abuse" mentioned in the abstract? Yes — since delivery requires a validated authorization bound to a real, cryptographically provable identity and purpose, synthetically generated fake identities without valid signed authorizations are rejected at the enforcement boundary.

40. What's the big-picture difference this makes for spam and fraud overall? Rather than networks trying to filter, score, or block spam after it's already been sent (a constant arms race), CVID prevents unauthorized communication from ever completing delivery in the first place — shifting the entire model from after-the-fact detection to pre-delivery, cryptographically enforced authorization.

Legacy Network Compatibility Objections

41. Doesn't this require replacing legacy telecom infrastructure like SS7 or old PSTN switches? No. The architecture is designed to sit at existing gateway points (SIP gateways, SMTP gateways, SMS/MMS gateways, session border controllers) rather than inside the legacy switching fabric itself, so operators are not required to rip out or replace SS7, PSTN switches, or core routing equipment.

42. What about older 2G/3G networks or basic feature phones that can't run modern cryptographic clients? Because enforcement happens at the network gateway rather than on the subscriber device, a legacy handset does not need to run any cryptographic software itself. The device continues to originate or receive calls/SMS normally; the authorization check happens in the network before the call or message reaches the terminating side.

43. Can this be deployed gradually, or does it require a "flag day" cutover across the whole network? It is designed for incremental, backward-compatible deployment. A carrier can enable enforcement at specific gateways or for specific traffic classes first, while unenforced traffic continues to flow through existing paths, allowing a phased rollout rather than an all-at-once migration.

44. What happens to a call or message from a network/operator that hasn't adopted CVID yet? Interoperability with non-adopting networks is a deployment/policy decision for the terminating operator — for example, such traffic can be routed through existing legacy filtering and authentication mechanisms (e.g., STIR/SHAKEN-style checks) until broader adoption occurs, rather than being unconditionally dropped.

45. Doesn't adding a new cryptographic layer make the system more fragile than the legacy network it's protecting? The system is deliberately fail-closed rather than fail-open, and consumption of authorization state is atomic and non-rollbackable, which is a security property, not a fragility one — an unavailable enforcement domain results in denial rather than an uncontrolled crash or bypass of the underlying network.

46. Is this only theoretical, or can it actually run on the hardware carriers already have? The specification describes deployment on existing gateway infrastructure using standard cryptographic primitives (e.g., HMAC-based signature validation), which are well within the processing capability of current-generation SIP/SMTP/SMS gateway hardware without requiring specialized new equipment.

Latency Objections

47. Won't adding cryptographic validation to every call or message slow down communication? The specification describes the cryptographic validation step (e.g., HMAC-based signature and nonce verification) as completing in microseconds per authorization check. This is far below the threshold a human caller or message recipient would perceive as delay.

48. What is the actual expected latency added per call setup or message send? Based on the HMAC-style validation described in the specification, the enforcement check itself is expected to add on the order of single-digit to low tens of microseconds of processing time at the gateway — negligible compared to typical call-setup signaling latency (which is usually tens to hundreds of milliseconds end-to-end on real networks).

49. How does microsecond-level validation compare to normal call setup time? Typical SIP call setup or SMS submission already involves network round trips measured in tens to hundreds of milliseconds. A microsecond-scale cryptographic check at the gateway is roughly 1,000–100,000 times smaller than that existing signaling latency, meaning it is not expected to be perceptible to callers or noticeably alter total call-setup time.

50. Does the latency get worse as call/message volume scales up (e.g., during peak hours or mass campaigns)? Because each validation is a bounded, constant-time cryptographic operation (signature check, nonce lookup, quota check) rather than a variable-cost search or filtering process, per-request latency is not expected to grow with overall network volume in the way that reputation-based or heuristic spam-scoring systems often do.

51. Does the "preview-to-unlock" staged execution add extra delay before a legitimate call connects? Preview mode is designed to let communication begin immediately in a bounded state (e.g., limited duration), with the unlock-token validation for extended communication handled as a separate, asynchronous step — so legitimate initial contact is not held up waiting for the extended-authorization check to complete.

52. What happens to latency if the enforcement gateway needs to reach a remote/distributed validation authority rather than validating locally? The specification allows for hardware-isolated enforcement domains that can be deployed locally at the gateway specifically to avoid remote round-trip delay; where distributed or quorum-based validation is used (e.g., for higher-assurance scenarios), that is a deployment configuration choice that trades some additional latency for stronger multi-authority guarantees, rather than a fixed property of the core architecture.

53. Isn't fail-closed behavior a latency risk — won't calls get delayed or dropped if the enforcement domain is briefly slow to respond? Fail-closed means unavailability results in denial rather than indefinite waiting; combined with microsecond-scale validation targets and gateway-local deployment, the design intent is to keep the validation path fast enough that timeout-driven denials are an edge case rather than a routine occurrence, though exact behavior under network stress is an implementation and deployment consideration for each operator.