Radio Network Design

ACM has the capability to poll many devices on a single radio network. However, there are physical limitations on the number of devices that can successfully coexist on a single radio network.

Serial Radio networks are limited because of bandwidth. Limiting factors include:

Limiting Factor	Notes
Number of devices	As you increase the number of devices, you increase the amount of traffic on the network.
Frequency to poll real time items	Determining the required poll rates will help design your network. For instance, a network with 200 devices may only be able to poll twice an hour for live data, while a network with 20 devices may be able to handle a poll every 2 minutes.
Number of real-time items advised per device	The amount of time to poll each device once will increase as more data is requested of each device
Types of history to be collected	History collection may take a substantial amount of time/bandwidth.
Protocol personality	All protocols are different and some protocols are more efficient than others at transmitting both real-time and historical data.
Radio network quality	Poor radio network may greatly reduce the amount of data you can retrieve from devices. Multiple retries to collect real-time and historical data can possibly bring networks down to a crawl.
Radio network speed	A balance must be found between network speed and network quality since higher speeds increase bandwidth but reduce communication quality.

Network Examples Table

Network Type	Retrieving History	Speed	Comm Quality	Number of Devices	Number of Items per Device	Number of Poll Cycles per Hour
Serial	Yes	9600	Good	200	40	1
Serial	No	9600	Good	200	40	3
Serial	Yes	9600	Poor	100	40	1
Serial	Yes	19200	Good	50	40	4
Ethernet	Yes	512,000	Good	20	40	30
Ethernet	No	512,000	Good	20	10	240
Ethernet	No	1,500,000	Good	5	10	960