Consumer Messaging Platform — WhatsApp-Class System  ·  View 16 of 23

Search, History, Backup and Restore

Where conversation data actually lives, what the platform can search, and how a user moves history to a new phone without the platform reading it.

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Trigger
Trigger
On device
On device
Protection
Protection
Off device
Off device
Recovery
Recovery
Message search
Message search
Search box, filters
Search box, filters
Full-text index over local DB
Full-text index over local DB
Index lives inside the encrypted DB
Index lives inside the encrypted DB
User & group search
User & group search
Name or number lookup
Name or number lookup
Local contact and group cache
Local contact and group cache
Hashed identifiers only
Hashed identifiers only
Discovery Service
Rate limited, no enumeration
Discovery Service...
Chat history
Chat history
Every accepted message
Every accepted message
Local chat DB is the record
Local chat DB is the record
Device encryption at rest
Device encryption at rest
Undelivered ciphertext only
TTL 30 d
Undelivered ciphertext only...
History transfer on device change
History transfer on device change
Backup & restore
Backup & restore
Scheduled or manual backup
Scheduled or manual backup
Snapshot plus media manifest
Snapshot plus media manifest
AES-256 with 64-digit key or password
AES-256 with 64-digit key or password
iCloud, Google Drive or provider store
iCloud, Google Drive or provider store
Key from HSM vault, 10 attempts
Key from HSM vault, 10 attempts
Storage management
Storage management
Storage usage screen
Storage usage screen
Usage by chat and by media type
Usage by chat and by media type
Blob retained 30 d for re-download
Blob retained 30 d for re-download
Selective delete and re-fetch
Selective delete and re-fetch
Search, History, Backup and Restore
Search, History, Backup and Restore
Blank cells are deliberate. On-device search never reaches the platform, by design.
Blank cells are deliberate. On-device search never reaches the platform, by design.
v 1.0 · owner Platform Architecture · date 2026-08
v 1.0 · owner Platform Architecture · date 2026-08Text is not SVG - cannot display

Search is local

  • Full-text search runs against the on-device index inside the encrypted database
  • The platform cannot search messages, because it cannot read them
  • Only user and group lookup reaches a service, and that is rate-limited against enumeration

Backup

  • Backups are encrypted with a user-held 64-digit key or a password-derived key
  • The key can be escrowed in an HSM vault that permits ten attempts, then locks permanently
  • The cloud provider stores an opaque blob and holds no decryption capability

Deliberate blanks

  • Empty cells in this matrix are the design, not an omission
  • Search and storage management have no off-device stage at all
  • That is what makes the privacy claim checkable rather than asserted
Solution Architecture v1.0 · Platform Architecture · 2026-0816-search-history-backup