TCPIP protocols - exactly defined.

We are pretty much geared up to use Carel/Emerson/Danfoss etc. workstations remotely to sites. Remote Desktop and VPNs work well for this. It is mostly about getting the right people the right keys to get into each store (or the corporate/regional network).
Remote service is a dream when the stores are networked up CORRECTLY *sigh*. Easy to get to from home/corporate. Easy all around.

BUT we need a handful of data (temperature, pressure, warnings, etc.) made available minute to minute to the BMS (see elsewhere on the forum for BMS references to Priva, Cylon, Siemens [Desigo], Trend, Johnson, etc.) and to enterprise systems (data stores for compliance and later data mining) and to energy management systems (like offerings from ABB, Schneider, Siemens Energy and so on).

So who amoung the refrigeration controls providers has the best open defined TCPIP data protocol and data model for data exchange?

Note we are happy to use the refrig. provider's offerings for pure refrig. analysis. They do an excellent job (think things like HACCP compliance, and refrigerant monitoring) and they provide great value, BUT the need is for cross referencing the refrig. data to other things like lighting, electric consumption, security, heating and cooling of the store.

The BMS systems are easy - they use LON or XML or BACnet - and as long as they have properly /exposed/ such data as is needed, then it is easy to read and cross reference.
Plants (automobile, food processing, paper, semiconductor, etc.) are even easy when the have Modbus RTU and Modbus TCP - though there is no data /model/ at least there is usually a data map somewhere on paper or on the Internet.

Refrigeration systems do not seem nearly so easy...
Anyone got XML? (and the schema/XSLT?)
Anyone got BACnet? (and the BIBBs?)
Anyone got SNMP? (and the MIBs?)
Anyone got Modbus RTU/TCP? (and a documented data register map?)

And I guess I am not looking for rumors ,
I am asking for someone who has /used/ TCPIP data exchange (out of the box) and can point to technical documentation about HOW to do such.

Thanks muchly, Putnam