# Changelog
This document provides an overview of changes between released versions of this specification. It is particularly important to consider this when implementing Registration and Query APIs which may support multiple releases simultaneously to ease upgrades in large facilities (see [Upgrade Path](docs/Upgrade%20Path.md)).

## Release v1.3
* Add additional network data for Nodes as required by IS-06
* Deprecate mDNS announcements for Nodes in registered mode
* Replace DNS-SD service type for Registration API
* Permit deprecated Node API connection management to not be implemented
* Add explicit requirements for `501` (Not Implemented) responses when features are not implemented
* Add support for future device and transport types
* Permit a Sender's `manifest_href` to be `null` when the transport type does not require a transport file
* Add `409` (Conflict) response code for registries with conflicting resources
* Add support for signalling authorization requirements
* Indicate potential for Source/Flow attributes and `caps` to be defined externally in the future
* Revise discovery process to ignore mDNS records when unicast records are available

## Release v1.2
* Add network interfaces and bindings to Nodes, Senders and Receivers
* Deprecate native Node API connection management interface
* Deprecate Sender and Receiver arrays within Devices
* Add signalling for active connections to unicast Senders, or non-NMOS Devices

## Release v1.1
* Add multi-protocol support and version identification to Node API `/self` and hence Query API `/nodes`
* Add `api_proto` TXT records to DNS-SD advertisements
* Add `api_ver` TXT records to DNS-SD advertisements
* Add guidance on use of DNS SRV record priority and weight
* Add support for secure WebSocket to the Query API
* Add support for `Upgrade` headers when using WebSocket
* Add paging support to the Query API
* Add advanced query parameter support for the Query API
* Add `device_id` to Flow attributes covering cases where a Device is a content transformer only
* Permit Senders without attached Flows to model a Device before internal routing has been performed
* Add support for exposing control endpoints from Devices
* Add support for muxed Sources and Flows (TR-04 and 2022-6)
* Add attributes for Sources and Flows for TR-03 set of media streams (raw video, raw audio, anc data)
* Ensure all API resources consistently advertise a `label`, `description` and `tags`
* Add support for signalling clocks exposed by Nodes and used by Sources

## Release v1.0
* Initial release
