Experimental Physics and
Industrial Control System

[email protected] (Jeff Hill) · Wed, 16 Jun 1999 10:46:22 -0600

> 
> What are your thoughts on using multicasting instead of "CARepeater
> mechanism"?
> 

The repeater solves the following problems:
1) pre-multicast kernels do not allow more than one process to 
bind to the same UDP port, and therefore broadcasts and unicasts
are delivered to only one process.
2) in most modern IP kernels UDP broadcasts can be sent to multiple 
processes, but unicasts can be sent to only one process.

I will definitely be looking at multicasting in future versions since 
multicasting is becoming universally available. At this point I 
believe that the new SENS vxWorks IP stack and most any other IP 
kernel will support multicasting. The SENS stack also supports 
DNS and NTP. Backwards compatibility may introduce some 
complications however, and at this point some of the details concerning
the above two issues and multicasting still need to be investigated.

Jeff

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System