Re: Sending xAP messages for sensor value change

[Kevin Hawkins <yahoogroupskh@xxxxxxxxxxxxxx>]

  Wow - that's a lot of zones !!

There is not actually a xAP security schema yet so you could either
create one , use another schema or just pop all the zones into one
message as you have been doing. I guess if you are exceeding 1500
characters in a single message then you should break the zones into
either functional types (I'm sure they're not all PIR's) or into areas
within the property or perhaps just numerically.  One of the problems
with lots of zones in one message is that it's harder to determine which
one(s) changed state but you could have a message that just lists
changed zones ie a 'status' message and an 'event' message. ( I sort of
do this with my C-Bus lighting groups)

I have xAPped my alarm and I have chosen to use the xAP BSC schema -
mainly because it is so pervasively supported.  For me this is far more
effective than one large messages and integrates nicely with other
software eg Cortex.

I only have about 45 zones and each of these is represented as a sub
address of the main xAP device.  Each zone has it's own individual
message that reports it's current state , whether it is armed and when
it last changed state.  I use a BSC text device for this as it matches
well.  BSC is a slightly more complex schema in that it is bidirectional
- meaning you can ask the xAP controller for the state of any zone or
indeed any group of zones if you construct your zone naming carefully eg
'all upstairs'.  You can also control endpoints via BSC should you wish
eg to exclude/disable zones perhaps.

I have also exposed the arm states as individual endpoints  - basically
the day/night/all/24 as well as any alarms (bells/silent/panic/tamper
and some other warns - line fail, comms fail, battery status etc. .  I
also report  four group statuses as my panel supports partitions into 4
independent 'areas'. However I do not permit the panel to be armed or
disarmed , or keypad emulation via xAP (for security reasons).  Others
might be comfortable with this but I chose not too.



K

On 05/10/2010 00:58, grumby89 wrote:
> I am working on xAPifying my alarm panel. I get notifications from it
when individual sensor states change, but I also get full zone reports (208
zones), as well as area and keypad status events.
>
> Currently when I get a full zone status report I have to break it down
into 2 xAP messages because they get too big. (zones 1 - 104 in one
message, the rest in the second)
>
> I have been studying this, and I'm wondering if I should be sending
one sensor status message for each sensor, rather than all of them combined
into one message.
>
> What are your opinions on this? I'm leaning towards sending zone
status messages for each zone. If it's a single zone state change send one
zone state message. If it's a full zone status report, send 208 messages
with current sensor status.
>
> Just wondered what the experts think
>
> Matt
>
>
>
>
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