The difference between the two generations of bridges is that the v2 bridge added support for Apple HomeKit and the CLIP v2 API [see next paragraph](#api-versions).
Additionally, it is possible to use OSRAM Lightify devices as well as other Zigbee Light Link compatible products, including the IKEA TRÅDFRI lights (when updated).
Bridges are accessed by means of the "CLIP" ('Connected Lighting Interface Protocol') Application Program Interface ('API').
There are two versions of CLIP - namely CLIP v1 and CLIP v2, which are referred to as API v1 and API v2 in the links below.
Signify has stated that any new features (such as dynamic scenes) will only be available on API v2, and in the long term API v1 will eventually be removed.
The API v2 has more features, e.g. it supports Server Sent Events 'SSE' which means that it is much faster to receive status updates in openHAB.
For this reason it is recommended to use API v2 for new openHAB installations.
But unfortunately the API v2 is not supported by older v1 (round) bridges, nor by newer v2 (square-ish) bridges if their firmware is under v1948086000.
You can create new API v2 things either via the automatic discovery services, via a `.things` file, or manually in the UI.
If things are created manually in the UI then you will have to enter all configuration parameters by hand.
You can use the [console command](doc/readme_v2.md#console-command-for-finding-resourceids) to discover the `resourceId` of all the things in the bridge.
You might also need to edit the names and types of your items, depending on the individual circumstances below.
When new API v2 things are created via the discovery services, then if a matching legacy API v1 thing exists, the new v2 thing will clone some of the the attributes of the existing API v1 thing.
And also, if a legacy API v1 thing exists and has items linked to its channels, then the new API v2 thing will replicate the links between those items and the respective new API v2 thing's channels.
1. In API v1 different things have different types (`0100`, `0220`, `0830`, etc.) but in API v2 all things have the same type `device`.
1. In API v1 different things are configured by different parameters (`sensorId`, `lightId`, etc.) but in API v2 all things are configured via the same `resourceId` parameter.
1. In API v1 some channel names contain underscore characters (`_`) but in API v2 they have changed to dashes (`-`) e.g `color_temperature` -> `color-temperature`.