Here is a list of all the available connectors and their release status.
Note: There is a maximum limit of connectors per FIN instance and that limit is 300. This is mentioned in the System Requirements.

"N/A" means the protocol doesn't have a notion of such a thing.

Connector	Transport Layer	Application Layer	Authentication	Proprietary Types	Read	Write	Schedules	Alarms	Histories	Release Status	FIN Version	Protocol Version	Note
BACnet	IP	AI, AO, AV, BI, BO, BV, MSV, MSI and MSO are mapped to haystack. All other object types can be read, along with all properties, with a little scripting.	N/A	Possible with minor scripting.	Yes	Yes	Yes	Yes	Yes	Released	As of 5.1.7	1.18
Haystack	HTTP(s)	All haystack types supported	SCRAM with SHA-256 HTTP Basic authentication	N/A	Yes	Yes	Supported only for nHaystack	Supported only for nHaystack	Yes	Released	As of 5.0	4.0	Haystack also has a rest API and documentation can be found here: https://project-haystack.org/doc/Rest
KNX	KNXnet/IP	Only simple DPTs supported (not structures or bitflags). ex: 1, 4, 5, 6 (except DPST 6-20), 7, 8, 9, 12, 13, 14, 16, 20, 23, 24, 28, 29, & 234. Actual support subject to change, depending on ETS version used.	N/A	N/A	Yes	Yes	N/A	N/A	N/A	Released	As of 5.1.5	N/A
Modbus	IP RTU with appropraite OS driver	FCs: 1, 2, 3, 4, 5, 6, 16	N/A	Connector is extendable allowing vendor specific FCs with a bit of development.	Yes	Yes	N/A	Yes	N/A	Released	As of 5.0
oBIX	HTTP(s)	All primitive types supported	HTTP Basic authentication	TBD	Yes	Yes	No (TBD)	No	Yes	Released	As of 5.0
OPC UA	UA TCP SOAP / HTTP(s)¹	All built-in types and structures supported as defined by OPC foundation's Opc.Ua.Types.bsd file	Only anonymous is supported	Not supported	Yes	Yes	N/A	Yes	Yes	Released	As of 5.0
Sedona	Sox over IP	TBD	Supported	TBD	Yes	Yes	No (TBD)	No (TBD)	TBD	Released	As of 5.0
SNMP	UDP TCP/IP	All types supported by installed MIBs.²	SNMPv2c & SNMPv3 Using MD5 or SHA	Supported by installing custom MIBs. Does not support SNMPv1.	Yes	Yes	N/A	No	N/A	Released	As of 5.0
SQL	Any included JDBC driver	All data types supported. Mapping to cur/write possible via jobs with minimal scripting	Supported	N/A	Yes	Yes	N/A	N/A	Yes	Released	As of 5.0
Other Protocols	SMTP				N/A				N/A	Released	As of 5.0
	Third-party connectors
MQTT	Please note, this is not available for F200

Service Encodings	File Formats
JSON					Yes	Yes				Released	As of 5.0
CSV					Yes	Yes				Released	As of 5.0
XML					Yes	Yes				Released	As of 5.0
Zinc					Yes	Yes				Released	As of 5.0
Trio					Yes	Yes				Released	As of 5.0
RSS					Yes	No				Released	As of 5.0
Green Button					Yes	No				Released	As of 5.0

Additional connectors:

Additional connectors can be found on stackhub.org. These are connectors developed by the community that can be used. Connector support is handled by the developer who made the connector.

Footnotes:

Security:
None
Basic128Rsa15
Basic256
Basic256Sha256
Mappings as:
ASN Null -> Haystack null
ASN Integer -> Haystack Number
ASN Octets -> Haystack Str
ASN Object Identifier -> Haystack Str

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