Simple Node Protocol Subset

(A few words about why this might be useful)

Simple nodes are defined as the leaf nodes that do basic layout control (input/output) operations. Gateways, configuration tools and other network-aware nodes are not simple nodes.

Messages Transmitted

Simple nodes may transmit any message, which must propagate correctly.

Messages Received

Simple nodes must receive any message addressed to them, plus the following unaddressed global messages:

• Verify Node ID – They need to receive this so that they can reply to it.

• Verified Node ID – They need to receive this because it's the reply to their own request, which might be used to e.g. locate a node for delayed sending of status

• Protocol Support Inquiry – They need to receive this so that they can reply to it.

• Protocol Support Reply - ?? Should this be here ??

• Identify Consumers, Identify Producers, Identify Events – because others will ask this of them

• Learn Event – so they can be programmed

• P/C Event Report – what they do for a living

In the future, additional MTIs will be defined. If simple nodes need to received them, the MTI will indicate that; see the MTI Allocation TN.

Gateways that are serving network segments (e.g. single CAN segments) that contain only simple nodes may suppress unaddressed (global) messages that do not contain simple-node MTIs.

Messages Not Received

Messages not listed in the section above do not need to be received by simple nodes.

A brief description of why the following message types are not necessary for simple nodes:

• Initialization Complete: Used to indicate that a node is newly available to the network. Simple nodes only care about their specific tasks, and by definition are not interested in the overall structure and availability of the network.

• Consumer Identified, Consumer Identify Range: These are of interest to gateways and configuration tools, but an individual producer does not need to know which (if any) nodes are consuming its produced events.

• Producer Identified, Producer Identify Range: These are of interest to gateways and configuration tools, but an individual consumer does not need to know which (if any) nodes are producing its consumed events.

Site hosted by

This is SVN $Revision: 1482 $