# Measure response time between vision client to Ignition to PLC when making a change to a boolean tag

**URL:** <https://forum.inductiveautomation.com/t/measure-response-time-between-vision-client-to-ignition-to-plc-when-making-a-change-to-a-boolean-tag/34478>\
**Category:** Ignition\
**Created:** [May 6, 2020, 9:31am UTC](https://forum.inductiveautomation.com/t/measure-response-time-between-vision-client-to-ignition-to-plc-when-making-a-change-to-a-boolean-tag/34478 "2020-05-06T09:31:40Z")\
**Posts on this page:** 1\
**Showing post:** 3

<div class="post-metadata">

**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [May 6, 2020, 12:32pm UTC](https://forum.inductiveautomation.com/t/measure-response-time-between-vision-client-to-ignition-to-plc-when-making-a-change-to-a-boolean-tag/34478/3 "2020-05-06T12:32:28Z")

</div>

> [@Sanderd17](#):
>
> OPC-UA works on top of TCP/IP, which is non-deterministic.

Not just OPC/UA, but practically all of your native PLC protocols. Non-deterministic. If you need deterministic communications, you need repeating UDP transmissions (or bare Ethernet frames).

@Yfactor, your line of questioning tends to be where engineers start when they realize SCADA packages tend to have trouble with momentary buttons driving booleans. This topic has been beaten to death numerous times on this forum:

[http://forum.inductiveautomation.com/search?q=momentary](http://forum.inductiveautomation.com/search?q=momentary)

This one is probably the most thorough (and contentious):

> [@Very Concerning Read/Write Issues. Important information for all users](http://forum.inductiveautomation.com/t/very-concerning-read-write-issues-important-information-for-all-users/18583):
>
> Hello Ignition Members, Disclaimer - All of our senior designers/programmers are qualified for their jobs where I work. These problems are described as I see them, they may not be exactly what happened. Therefor they are to be used for troubleshooting the issue only. Thank you. We are in contact with some ignition developers and are desperately trying to fix this problem. This is a GLOBAL problem therefore it won’t be affecting just us. It may be affecting anyone who is using ignition well. Ti…

---

_[View the full topic](https://forum.inductiveautomation.com/t/measure-response-time-between-vision-client-to-ignition-to-plc-when-making-a-change-to-a-boolean-tag/34478)._