Echelon i.LON SmartServer 2.0 Power Line - Manual (Page 142)

128 Appendix A - Glossary
Glossary
Alternative Proxy
A repeating device that can directly communicate with a given target device if the current proxy agent
fails.
Direct Communication
State when a repeating device can directly communicate with the SmartServer. A device that has
direct communication does not use a repeating chain to receive a network message from the
SmartServer.
Enhanced LonTalk Proxy Protocol
A protocol in which the SmartServer instructs the Neuron firmware in the devices on the power line
when to repeat the network messages they receive. This protocol enables the network management
commands transmitted by the SmartServer to reach their intended target devices, overcoming
impediments posed by power line channels such as excessive noise and long distances between
devices.
Frequency
The frequency carrier of the signal. A frequency can be either a primary frequency or a secondary
frequency. A primary frequency meets national standards for accuracy and operates without the need
for calibration against an external standard. A secondary frequency does not have inherent accuracy
and therefore must be calibrated against a primary frequency standard. For more information on the
use of these frequency carriers on a L
ON W ORKS power line channel, see the L ON W ORKS PLT-22 Power
Line Transceiver User’s Guide (110kHz - 140kHz Operation).
Hop
Point on the repeating chain in which a network message is relayed from one device (including the
SmartServer) to another.
Margin
The amount that the data signal is greater than the noise level.
Proxy
A repeating device that can directly communicate with a given device.
Proxy Agent
The last repeating device in a repeating chain prior to the target device.
Proxy Source
The sender of the network message, which is always the SmartServer.
Proxy Zone
The recipient of a network message in a repeating chain, which may either be a repeating device or the
target device.
Repeating Chain
The ordered list of repeating devices required for a network message to reach a given target device.
Repeating Device
A Neuron-hosted or host-based ShortStack L ON W ORKS device with a PL-3120 ® , PL-3150 ® , or
PL-3170 smart transceiver that accepts a network message and forwards it to another L ON W ORKS
device. When a repeating device receives a network message, it forwards the message to either the