Собственно два вопроса:
1) А какая вообще разница между BACnet/IP и BACnet/Ethernet? И за каким надо было городить две разновидности?

2) Какой производитель специализируется на маршрутизаторах BACnet с различными транспортными уровнями?

Хотел бы к этому вопросу еще добавить BACnet на ARCnet и BACnet на MS/TP!!!

Ответ на первый вопрос так и не прозвучал!

What about connecting BACnet systems together? What networking options are there for BACnet?

Good point! Up until now I have just been talking about the BACnet object-oriented model and the various services or message types. You still need to pick an appropriate network technology to connect everything together. The BACnet committee spent a lot of time on this part of the standard. We ended up with 5 different options, each of which fills a particular niche in terms of the price/performance tradeoff. The first is Ethernet, the fastest at 10 Mbps with 100 Mbps also recently available. ("Mbps" stands for "millions of bits per second.") Ethernet is also likely to be the most expensive in terms of cost per device. Next comes ARCNET at 2.5 Mbps. Both Ethernet and ARCNET can use a variety of physical media � coaxial cable, twisted pairs, even fiber optic cable. For devices with lower requirements in terms of speed, BACnet defines the MS/TP (master-slave/token-passing) network designed to run at speeds of 1 Mbps or less over twisted pair wiring. Echelon's LonTalk network can also be used on various media. All of these networks are examples of "local area networks" or LANs. BACnet also defines a dial-up or "point-to-point" protocol called PTP for use over phone lines or hardwired EIA-232 connections. A key point is that BACnet messages can, in principle, be transported by any network technology, if and when it becomes cost-effective to do so.

Классная картинка. Может такая есть и на лон?

В аспирантуре все философия, математика, английский... Картинкам в садике учили