SEND is the universal device entry point. Choose a nearby or trusted destination, choose what should move, review the exact dispatch plan, then continue. BEAM remains the transfer technology; specialized engines keep their own security boundaries underneath.
SEND is the universal device entry point. Pick the destination first, choose what should move, review the dispatch plan, then continue explicitly. BEAM keeps the product experience unified while each existing transport keeps its own payload, limits, verification and acceptance rules.
DEVICE→WHAT→CONTINUE
01 / DEVICE
Where should this go?
No background presence. Trusted devices are stored only in this browser and reconnect only after explicit mutual proof.
Describe the job, not the transport. SEND chooses the narrow existing engine that already owns it.
03 / CONTINUE
Review before anything starts.
SEND stages locally only after this explicit action, then opens the existing transport or trusted-device authentication flow.
DISPATCH PLANWAITING FOR INPUT
Choose a destination first.
DEVICE / Choose a device · WHAT / Nothing selected
ADVANCED / DIRECT ENGINEBEAM Safe SendOpen the original one-file BEAM sender/receiver controls directly.
BEAM / SAFE SEND + NEARBY RECEIVE V1.5
CHECKING SIGNALINGDIRECT MODE
01 / SELECT LOCALLY
FILE PAYLOAD NEVER ENTERS SIGNALING STORAGE / QR ONLY CARRIES A TEMPORARY ROUTE
SESSION / IDLEChoose a direction to begin.
The receiver joins by QR or code.
Connection metadata expires automatically. File bytes travel over the encrypted WebRTC channel.
TRANSPORT WEBRTC DATACHANNEL / DTLSCHUNKS 64 KIB / BACKPRESSUREINTEGRITY SHA-256SESSION 10 MIN / ONE USE
SEND / TRUSTED DEVICES
Pair once when you need to. Reconnect only when you choose.
Saved browser trust is optional. First trust uses ECDH plus a human verification code; later sessions use rotating rendezvous and mutual proof before a queued SEND action can continue. There is no background presence or cloud device list.
SEND does not collapse transfer semantics into a universal payload protocol. One file remains BEAM Safe Send, short text and URLs remain CLIP, larger supported text remains LINK, collections remain TRAY, workflow continuation remains CONTINUE, and current-view continuity remains a trusted pathname-only Device Hub action.
Direct P2P is preferred where the owning transport supports it. Receiver/open/continue actions remain explicit, and every specialized engine keeps its existing limits and verification behavior.
BEAM SAFE SEND / IMPLEMENTED PROTOCOL V1.5
Every stage is visible and bounded.
00 / SAFE SENDInspect before transfer.
File Intelligence identifies the content, computes the complete SHA-256, counts metadata signals and scans supported files for credential plus deterministic PII patterns locally. High-risk privacy or structural signals require explicit sender review.
01 / CREATEShort-lived session.
Either side can create the short-lived route. Signaling keeps only bounded session data; file name and MIME stay off signaling and move only after the protected peer channel exists.
02 / PAIRQR or eight characters.
Sender-first QR opens the receive flow. Receiver-first QR opens the send flow. Both contain only a temporary route/code and accept exactly one counterpart.
03 / CONNECTDirect or relayed WebRTC.
ICE negotiates the route. TURN is a transient network fallback, never a payload archive.
04 / CONTROLExplicit acceptance.
The receiver sees name, type and size before selecting a destination and allowing transfer.
05 / STREAM64 KiB chunks.
Backpressure protects browser memory while progress, throughput and estimated time stay visible.
06 / VERIFYSHA-256 on both devices.
The receiver keeps the file only when its computed digest matches the sender’s final digest.
SERVER BOUNDARY
Coordinate less. Store no payload.
BEAM v1.5 has a strict 512 MB product limit and a ten-minute standard session lifetime; SCAN can request a bounded 30-minute receiver route for multi-page Phone Bridge work; SIGNPAD uses a bounded 20-minute route for handwriting capture. Safe Send now includes deterministic PII preflight, and WIPE can stage a verified copy locally for one-time same-browser handoff. Those limits are deliberate and visible.
SIGNALING PROCESSES
Temporary pairing identifier
Bounded file size only before peer channel
WebRTC SDP and ICE metadata
Short-lived TURN credentials
SIGNALING NEVER RECEIVES
File name or MIME before protected peer channel
File payload chunks
Permanent download copies
Transfer-content indexes
User accounts or file histories
BEAM SAFE SEND / RELEASE PROOF
SAFE SENDLENS + SECRET + PIIPAIRINGTWO-WAY QR + CODETRANSPORTWEBRTC + TURNFLOWBACKPRESSUREINTEGRITYSHA-256CONTROLRECEIVE QR + ACCEPTEXPIRY10 MINUTES
Public availability still depends on deploying the supplied signaling endpoint and Coturn configuration, then completing cross-network device verification on the production host.