Re: XPL - XAP

[Kevin Hawkins <lists@xxxxxxxxxxxxxxxxx>]

As ever the caveat as I'm a xAP user- I've tried to be impartial and
balanced here but I don't use xPL extensively so interpret accordingly ....

I think it's important to position xAP (and xPL) correctly.  They
are both a 'protocol' (not an application) devised to enable devices to
exchange information and control each other in a very easily implemented
and understable way. What I mean by that is that the information in the
small informational packets is human readable and visible to all devices
on a xAP network (no private conversations or binary data exchanges take
place).  Leveraging the protocol is therefore relatively easy for people
with a  bit of programming savvy.  What the x protocols are not is an
end user application , what they are , are (excellent) enablers to make
it all possible, but in the scheme of things they are fairly low level
and remian hidden mostly - like TCP, UPnP or EIB

Having said that xPL presents most of its configuration and
administration via a partner application called xPL HAL.  xPL HAL is
essentially an application that implements the core xPL  protocol to
provide an end user presentation for implementing a whole system,
including configuration, scripting and a logic engine. xPL HAL also has
features to make scripting a lot more accessible to people who are not
script programmers.  So essentially most xPL users have a bundled
application with xPL HAL to tie it all together and get you going.
There may still be a desire with xPL HAL to present the information in a
more graphical way but this could be achieved with another external
application too, it isn't required that such functionality sit all in
one place. xPL and xAP tend to distribute functionality across a
network.  xAP on the other hand has xAP Desktop and xAP Floorplan as its
equivalent engine. Again this provides a script and logic engine but
expands on the end user presentation side to either offer a full
graphical interaction with your Windows based desktop or access via a
web browser (xAP Floorplan) using a near realtime display (which has
previously been a problem with a web browser). Where these xAP
applications are not as extensive as  xPL HAL are in configuration and
the wizard/determinator script aids that it offers. So  advantages and
disadvantages in each.  BTW xAP Floorplan supports xPL/xAP bridging
without needing to script and even some intelligent schema conversions
between the two.

xAP also has support for many commercial HA applications (usually
via plugins) to allow you to integrate xAP devices within your favourite
application.  We took the view that building heavyweight HA applications
was something we could never maintain so offering support for other
favourites was the way to go. The most prevalent of these seems to be
HomeSeer and a big plus is every device that is supported in HomeSeer (
from the vast library of plugins) also becomes accessible to xAP.
There is also support for MisterHouse, Charmed Quark, XLobby, VSCP (and
another in teh works). I believe MisterHouse supports xPL too.

What I'm trying to say - is there are two issues here, firstly
using xAP or xPL is like using a  building block that can work singly or
alongside other mechanisms/protocols .  To an extent xAP and EIB occupy
the same area - they are both protocols. Secondly you need to select an
end user control engine and possibly a visual interface application. If
these support xAP or xPL that's great but there are really important
choices to be made here on the capabilities offered and so you should
spend time considering what you need.  One great plus about having xAP
or xPL is that it is relatively easy to add new devices if you have a
bit of programming knowledge.

Kevin