How to send large data (1mb-2mb) in a message

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How to send large data (1mb-2mb) in a message

I have an RTI DDS program that I would like to make its upper limit for data sent being between 1mb-2mb. I know that RTI has a limit by default which I believe is 9kb. 

How would I edit my QOS Policy file to allow the sending of 1mb-2mb files without any issues encountered?


This is my QOS File I currently have Could not put in here or would trigger spam filter.

Gerardo Pardo's picture
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Joined: 06/02/2010
Posts: 601


The UDP limitation is 64KB, but DDS can fragment and re-assamble larger data samples so there is no hard limit on the upper size of the data sent. However some Qos configurations can help make that more efficient and also control the bandwith used by those large data flows so that they do not starve other flows.

There is an example of how to send large data samples on the File Exchange bundle This was built for an earlier version of Connext DDS (5.0) but it should be straighforward to adapt it to more recent versions of Connext DDS.

Note that in 5.2 and later there are also some builtin Qos profiles that address this problem. For example the one called "User.Generic.StrictReliable.LargeData.FastFlow"