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Agent OS
AOS-HW-007 Normative foundation

Cellular and Telephony Program

Cellular and Telephony Program: scope, decisions, requirements, evidence, risks, and traceability for the Agent OS programme.

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Cellular and Telephony Program

This specification treats hardware support as an evidence programme with explicit documentation rights, recovery paths, quality gates, and replacement strategies.

Table of Contents

Purpose and Scope

Area: Hardware Programme.

This specification treats hardware support as an evidence programme with explicit documentation rights, recovery paths, quality gates, and replacement strategies.

This document owns the semantics implied by Cellular and Telephony Program. It does not assert that every described subsystem already exists. It defines the target model, constraints, evidence needed to trust an implementation, and the boundary with adjacent documents.

Normative Position

  1. Separate modem transport, SIM/eSIM, registration, packet data, SMS, emergency behavior, IMS, audio routing, policy, diagnostics, and certification.
  2. Prefer externally connected documented modems for early native contracts.
  3. Do not infer voice support from packet-data support.

Operating Model

The operating model is contract-first and evidence-driven. A component declares its authority, resources, lifecycle, error model, cancellation and timeout behavior, observability, version, and compatibility promise. Backends are replaceable only when the same conformance suite passes and no forbidden platform type leaks into portable layers.

Implementation proceeds through a reference model or mock, deterministic QEMU evidence where relevant, documentation-first physical hardware, and quality-hardware evidence. Pixel 9 adapters remain quarantined according to ADR-0004.

Requirements

  • R01. Separate modem transport, SIM/eSIM, registration, packet data, SMS, emergency behavior, IMS, audio routing, policy, diagnostics, and certification.
  • R02. Prefer externally connected documented modems for early native contracts.
  • R03. Do not infer voice support from packet-data support.
  • R04. Specify normal, partial, denied, timeout, cancellation, restart, upgrade, and permanent-failure behavior.
  • R05. Expose structured diagnostics without leaking secrets or vendor-specific implementation details.
  • R06. Link material unknowns to a claim and, when testable, an experiment with an owner and gate.
  • R07. Update affected documentation and task data when evidence changes the model.

Failure and Degradation

Degradation must be explicit rather than accidental. The system reports capability absence, reduced quality, unavailable provider, stale data, or unsafe condition through typed states. It must not silently fall back to broader authority, unrestricted legacy execution, unverified firmware, lossy data migration, or irreversible agent action.

Recovery defines what state is retained, reconstructed, re-enrolled, compensated, or intentionally discarded. Unsupported hardware or providers are rejected at binding time where possible.

Evidence and Acceptance

  • State-machine trace replay.
  • Data/SMS/voice tests by operator and region.
  • Certification and partner evidence before “phone” claims.
  • Evidence records target identity, hardware revision, firmware, source commit, toolchain, configuration, seed, timestamps, artifacts, expected result, actual result, and reviewer.
  • Acceptance requires the referenced tasks to meet their own criteria; prose completion is not implementation completion.

Implementation Obligations

Task Obligation Priority Gate/Milestone Verification
AOS-PLAT-036 Implement audio service and graph contract P1 M4 latency/drift/glitch, route changes, device removal, permission, suspend and crash tests
AOS-PLAT-040 Specify portable cellular and telephony service contracts P1 M5 map MBIM/QMI/module/data/SMS and unresolved IMS paths without claiming unsupported functions
AOS-OPEN-057 Integrate open-phone modem hardware with native cellular service P1 M6 registration/data/SMS tasks, modem crash/replug/reset, suspend and capability isolation
AOS-CELL-000 Cellular and Telephony Program epic P1 Continuous monthly project review and gate reconciliation
AOS-CELL-001 Define cellular capability decomposition and product claims P0 M3 review against 3GPP/GSMA/Android decomposition and open module cases without importing their APIs
AOS-CELL-002 Shortlist documented cellular modules and evaluation kits P0 M3 official-source/vendor-response review and sample availability/pricing check
AOS-CELL-003 Commission lawful cellular test environment P1 M4 controlled registration/data/SMS test and emergency-path tabletop with counsel/lab guidance
AOS-CELL-010 Implement native USB/serial/AT modem transport P0 M5 malformed/partial/unsolicited/timeout/reset/replug/driver-crash and command-injection tests
AOS-CELL-020 Implement native MBIM/QMI transport and control proof P0 M5 EXP-041 connect/register/session/status/reset/invalid-message scenarios and forbidden-dependency scan
AOS-CELL-021 Implement modem registration and lifecycle state machine P0 M6 SIM absent/locked, denied/roaming, coverage loss, modem crash/reset, suspend, firmware mismatch and rapid toggling
AOS-CELL-022 Implement physical SIM access and secret boundary P0 M5 wrong PIN/PUK, brute-force/rate, process crash, removal, secure-input/journal and unauthorized APDU tests
AOS-CELL-030 Deliver native cellular data and SMS prototype P0 M6 EXP-042 registration/data/DNS/large transfer/SMS send-receive/duplicate/loss/reset/roaming policy cases
AOS-CELL-031 Harden cellular recovery, suspend, roaming, and power behavior P1 M8 hours-long coverage/modem/suspend/roaming/data-limit fault campaign with power measurement
AOS-CELL-040 Model and evaluate eSIM lifecycle and partner requirements P1 M9 EXP-043 tabletop and available evaluation path; lost device, transfer, rollback and malicious profile scenarios
AOS-CELL-041 Integrate modem-assisted GNSS where supportable P3 M8 known-location/time comparison, cold/warm start, denial/background, no-network and suspend tests
AOS-CELL-042 Define emergency-calling safety boundary before voice work P0 M9 tabletop and accredited/operator consultation without live unauthorized emergency calls
AOS-CELL-050 Establish native voice and IMS feasibility P0 M9 EXP-044 with written partner evidence and lawful lab/test-network demonstration where available
AOS-CELL-051 Implement telephony audio-routing contract and test path P1 M9 route changes, mute/privacy, echo/latency, device loss, suspend, call interruption and failure tests

The canonical task CSV contains 5 additional linked tasks.

Risks and Open Questions

  • IMS and emergency calling are vendor-, operator-, region-, and certification-dependent.
  • Baseband firmware remains a separate high-risk computing domain.
  • RF and legal certification costs dominate late hardware changes.
  • Open-question rule: an unanswered high-impact question becomes a claim/experiment record and cannot be hidden in meeting notes.
  • Stop rule: work stops or changes track when legal rights, recovery, debug access, safety, or the required evidence path is unavailable.

Related Documents

Planning Reference Anchors

Audio Routing

AOS-PLAT-036 — Implement audio service and graph contract; AOS-CELL-051 — Implement telephony audio-routing contract and test path

Certification Consequences

AOS-CELL-052 — Build cellular certification and carrier engagement plan

Data And Sms

AOS-CELL-030 — Deliver native cellular data and SMS prototype

Emergency Calling

AOS-CELL-042 — Define emergency-calling safety boundary before voice work

Gnss

AOS-CELL-041 — Integrate modem-assisted GNSS where supportable

Modem State Machine

AOS-CELL-021 — Implement modem registration and lifecycle state machine

Module Selection

AOS-CELL-002 — Shortlist documented cellular modules and evaluation kits; AOS-CELL-060 — Secure cellular module vendor and FAE relationships; AOS-ODM-024 — Define production cellular/RF module and antenna architecture

Native Cellular Stack

AOS-OPEN-057 — Integrate open-phone modem hardware with native cellular service; AOS-CELL-010 — Implement native USB/serial/AT modem transport; AOS-CELL-020 — Implement native MBIM/QMI transport and control proof

Product Claim Levels

AOS-CELL-080 — Decide connected-device versus full-phone product route

Reliability And Power

AOS-CELL-031 — Harden cellular recovery, suspend, roaming, and power behavior

Separate Capability Gates

AOS-PLAT-040 — Specify portable cellular and telephony service contracts; AOS-CELL-000 — Cellular and Telephony Program epic; AOS-CELL-001 — Define cellular capability decomposition and product claims; AOS-P9-095 — Test Pixel 9 modem isolation and native service boundary feasibility

Sim And Esim

AOS-CELL-022 — Implement physical SIM access and secret boundary; AOS-CELL-040 — Model and evaluate eSIM lifecycle and partner requirements

Test Environment

AOS-CELL-003 — Commission lawful cellular test environment

Voice And Ims

AOS-CELL-050 — Establish native voice and IMS feasibility