Re: [Embedlets-dev] Interested in sharing a J2EE perspective

[Gregg G. W. <gr...@sk...>]

>> We've added 100's 
>> of devices into systems day and night with zero impact to the existing 
>> devices.
>
>Is the 'we' here Cyte employees or customer IT personnel?  Who decides what
>types of devices are deployed and where?

Field technicians and IT staff, depending on the customer and the application.

>> The systems don't have per device configuration, or automatically 
>> recognize and configure the system for the new devices if device specific 
>> configuration is needed.  
>
>Can you give an idea again of what types of devices are typically connected to
>these systems?  What are some of the things they are doing?  Are they only
>monitoring or are some of them also doing control?

Metering equipment as well as control equipment.

>It sure would be interesting to visit one of your installations!  The Cyte
>website shows that Cyte has a Midwest regional contact.  Does Cyte have any
>installations like you described above anywhere near Ohio?

Not Yet.  We have pipeline based equipment throughout the lower midwest and 
going west into wyoming.  The equipment is not that special Ted.  It's mostly 
the arcom control systems director.  It is monitoring and controlling 
equipment via modbus and/or digital and analog I/O.  The director would be an 
outpost class device.  It does all the work of a realtime environment.  We 
just send it things to do (mostly via modbus) for certain controls.  It also 
has scheduled reporting and exception based reporting that it is performing 
unattended.

We use a proprietary binary protocol from the directors in many cases.  In 
others, we shoot back XML.  It just depends on what is the easiest.

These programmable controllers are available everywhere.  What is not being 
done is the publish/subscribe model.  Instead, everyone is polling these 
devices with modbus or similar protocols.  Polling doesn't scale well to large 
numbers of devices, comming from a single source.

So, we do the polling at the Director devices, and then have them publish the 
data back into the enterprise.  There is a whole series of error management 
strategies that come into play when you have networking between the enterprise 
and its vital data.  For each type of application/data, we've engineered 
solutions that make sure the data can be retrieved within reasonable 
contraints of communications failures.  There are things like 30days of 
history that needs to be archived at the remote sites so that someone can 
drive out there and collect manually if needed.  Some of the end devices do 
this themselves already.  Some need the director to buffer data.  So, it needs 
certain size flash for certain apps.

It's really an end to end engineering job.  But, once you have the pieces 
engineered, then anyone can drop them into the network and plug them together.

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gr...@cy...  (Cyte Technologies Inc)