Handshake: presence confirmed when two devices meet.

The handshake is the confirmation of real proximity between two devices. When a phone comes close to another phone, to a POS or to a GL Station, they exchange a handshake and generate a meeting event, with time and context.

It is point-to-point presence, without depending on GPS. That is why it works very well indoors, where the satellite signal fails: inside a store, a stadium, an industrial plant or a hospital.

The rule is simple: for the handshake to happen, one of the apps must be open, in the foreground. The other can be in the background. The meeting becomes an event with duration and context, ready to use.

This opens up cases that location alone cannot solve: confirming that the customer stood in front of the counter, measuring queues and service, registering encounters at events or validating proximity between staff and an asset.

Under the hood, the handshake uses the Group Link network’s proprietary and patented BLE protocol, with a range of up to 30 meters. The event carries the essentials: which points met, when, for how long and in what context. No personal data travels in the handshake: the identifiers are opaque, and only your base can relate them to a session or user.

The same mechanism applies to devices and anchors: a phone with the SDK that crosses paths with a GL Station, a POS or an integrated TV generates the same type of event, with the advantage that the anchor has a fixed, known location.