SIASERVER

The SIASERVER driver implements a SIA (Security Industry Association protocol) server, specifically following the DC-09 specification. It has been developed and tested with HSYCO acting as a SIA DC-09 server, though compatibility with other SIA protocol variants is possible but not guaranteed.

Communication

The driver listens for incoming TCP connections from SIA-compatible devices, decodes the received messages (including optional decryption), and exposes the most relevant fields as datapoints. It also allows sending control or response messages.

HSYCO Configuration

Add a SIASERVER I/O Server in the I/O Servers section of the Settings and set its parameters:

Name	Default	Values	Description
port	6410	number	TCP port number on which the server listens
threads	1	number	number of threads used to handle connections
timestampdelayoffset	20	0–86400	maximum allowed time (in seconds) in the future for a valid message timestamp. If set to 0 the timestamp validation is disabled
timestampadvanceoffset	40	0–86400	maximum allowed time (in seconds) in the past for a valid message timestamp. If set to 0 the timestamp validation is disabled
encryption	false	true	enable AES encryption based on AES/CBC/NoPadding
		false	disable encryption
encryptiontype	aes-128	aes-128	use aes-128 encryption
		aes-256	use aes-256 encryption
secret		string	secret key for AES encryption. Must match the key configured in the SIA device

High Availability

• Shutdown when inactive: defaults to false

Datapoints

The most important datapoints are “event”, “crc.error”, and “timestamp.error”.

“event” contains the meaningful part of the SIA message. All other datapoints are useful for debugging purposes.

“timestamp.seconds.elapsed” can be useful for writing an EVENTS program that sends a notification if no SIA messages are received for an extended period of time.

Datapoint	Type	R/W	Description
account	string	R	the SIA account number that sent the message
crc.calculated	hex string	R	locally calculated CRC based on the received message payload
crc.error	1	R	CRC error
	0	R	no CRC errors
crc.received	hex string	R	CRC value received in the message
crcpayload	string	R	message payload used to compute the CRC
decrypted.message	string	R	decrypted received message body, if encryption is enabled
event	string	R	SIA event message. Could be empty (e.g. NULL message)
last.response.sent	string	R	the last response message sent to the SIA device
last.command.sent	string	R	the last RSP command sent to the SIA device
received.raw	string	R	raw incoming message, as received
seq	number	R	sequence number of the message
system.timestamp	HH:MM:SS,DD-MM-YYYY	R	timestamp UTC+00:00 when the message was received by HSYCO
timestamp	string or "unknown"	R	timestamp UTC+00:00 extracted from the message (if present)
type	string or "unknown"	R	received message type parsed from the protocol
timestamp.error	1	R	timestamp error
	0	R	no timestamp errors
timestamp.seconds.diff	number	R	difference in seconds between system timestamp and SIA message timestamp
timestamp.seconds.elapsed	number	R	number of seconds since the last SIA message was received. Updated every 60 seconds of when a new message is received
command	<rcvr>-<pref>-<payload>	W	send the command to the SIA on-premises equipment
commands.queue	clear	W	clear the commands queue
commands.queue.length	clear	R	the length of the commands queue

I/O Server Logic

This I/O Server listens for SIA protocol commands on the TCP port specified in the driver options.

Upon receiving a valid SIA command:

• It responds with an ACK (Acknowledge) if the timestamp check is either correct or disabled.
• Otherwise, it responds with a NAK (Negative Acknowledge) and the current timestamp.
• When a NULL command is received, the server responds with an ACK unless there are commands queued. In that case, it sends the oldest command from the command buffer.

This logic applies identically in both encrypted and clear (unencrypted) modes.

Sending Commands

You can send a command to a connected SIA device by writing a value to the command datapoint.

SIA commands to be sent are queued in a first-in, first-out (FIFO) buffer and transmitted one at a time upon receipt of a NULL message from the on-premises equipment. Therefore, to facilitate immediate command transmission, it is recommended to reduce the time interval between consecutive NULL messages to a few seconds.

For encrypted messages, commands will have the identifier RSP. The timestamp, in SIA format, will be appended and encrypted at the end of the message, just before the carriage return.

The syntax is the following:

<driverid>.command = <rcvr>-<pref>-<payload>

Where:

• rcvr: receiver number (optional)
• pref: account prefix (mandatory)
• payload: the SIA message payload. The part before the brackets may not match the account number inside the message data.

Examples:

#12345[#12345"TEST"]

#12345[#7890"TEST"]

Programming in EVENTS:

TIME : IO sia.command = "0-0-#12345[COMMAND]"

In this case:

• receiver = 0
• prefix = 0
• payload = #12345[COMMAND]

If encryption is enabled, only `COMMAND]` is encrypted.

TIME : IO sia.command = "2-[COMMAND]"

• receiver omitted
• prefix = 2
• payload = [COMMAND]

Another example in JS:

TIME : {
   ioSet("sia.command", "0-[#12345|\\\"TEST\\\"AWAYARM,1]");
}

Payload = #12345|"TEST"AWAYARM,1 — only the part from `[` to the end is encrypted.

Release Notes

3.10.0

• initial release

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SIA is a trademark of Security Industry Association

Category:

• I/O Server