Feature #12735

Add support for large messages

Added by Richard Neswold almost 5 years ago. Updated 12 months ago.

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Early 2015, we developed a protocol to allow ACNET to send and receive messages larger than 64K. acnetd needs to implement this feature.

ACNet UDP Long Messages.pdf (104 KB) ACNet UDP Long Messages.pdf Latest specification Richard Neswold, 05/20/2016 09:57 AM


Feature #20698: Large Messages: Support the client APINewRichard Neswold


#1 Updated by Richard Neswold about 4 years ago

acnetd source has been placed in Redmine. The master branch is what's running in the control system. I created a large-packets branch which contains the efforts of this issue.

#2 Updated by Richard Neswold over 2 years ago

  • Category set to acnetd
  • Target version set to acnet v2.0

This is a major change so we target it for v2.0.

#3 Updated by Richard Neswold over 2 years ago

  • Due date set to 08/28/2018
  • Start date changed from 05/20/2016 to 08/28/2018

due to changes in a related task: #20698

#4 Updated by Beau Harrison 12 months ago

I'm adding a relevant conversation from Slack for reference:

Beau Harrison:

Rich Neswold:
Happened across this post and reread it. This could be the answer for ACNET Large Message support! It’s supported by Linux, BSD, OSX, Windows and VxWorks 6.4 (and above.)
They talk about one SCTP connection that can open “channels” so that, while one process is writing a large message, smaller messages can be written on other channels (i.e. the network stack will interleave the message chunks and rebuild them on the other side.) This is exactly what we were trying to do!
The downside is that all ACNET implementations would need to be tweaked/rewritten whereas our solution is backward compatible with current ACNET. However, it seems insane not to use something that’s already written and a standard.

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