Hello everyone.

We have decided to phase out the Mixed Reality Forums over the next few months in favor of other ways to connect with us.

The first way we want to connect with you is our mixed reality developer program, which you can sign up for at https://aka.ms/IWantMR.

The plan between now and the beginning of May is to clean up old, unanswered questions that are no longer relevant. The forums will remain open and usable.

On May 1st we will be locking the forums to new posts and replies. They will remain available for another three months for the purposes of searching them, and then they will be closed altogether on August 1st.

So, where does that leave our awesome community to ask questions? Well, there are a few places we want to engage with you. For technical questions, please use Stack Overflow, and tag your questions using either hololens or windows-mixed-reality. If you want to join in discussions, please do so in the HoloDevelopers Slack, which you can join by going to https://aka.ms/holodevelopers. And always feel free to hit us up on Twitter @MxdRealityDev.

Receiving UDP multicast packets on Hololens

TakouhTakouh
edited November 2018 in Questions And Answers

Hi,

Is Hololens able to receive UDP multicast packets by default? Or is there a setting which makes that happen?

I have a Unity application which uses a udp multicast message passing system. The udp multicast message passing system is built into a .NET dll. The dll is linked to the application and it works fine on a desktop.
However when I deploy this application on Hololens, I don't receive any error, but I do not receive any messages. I am wondering if this is because the Hololens drops udp multicast packets or if it is due to the dll not being built against UWP.

I would appreciate any input on this.

Tagged:

Answers

  • I think that you can. If I remember right, I used UDP multicasting as the basis of how devices could find each other a network for a shared holograms type solution.

    I wrote it up here although I can't promise that it's any good or suitable for any particular purpose nor that it hasn't got a little out of date with respect to current SDK versions.

    In my case, I shared some source code which I then compiled both for .NET 3.5 and for the UWP and I ended up building that into a console app, a 2D XAML based app and a 3D Unity based app and sending messages back and forth.

    You might want to check your application manifest to ensure that it has the right capabilities - e.g. I suspect "Private Networks" is needed to allow for multicasting around your local network. I noticed that I wrote down that I did this when writing the 2nd post in that series.

    I hope that helps and good luck with your code here :smile:

  • Thank you for your response!

    I am able to send and receive UDP multicasts to and from Hololens. However, the connection performance is quite dismal. The round-trip time for every sent package increases over time from a few milliseconds to tens of seconds and there is a considerable number of message losses.
    The very same code, works perfectly fine on other platforms (Desktop Windows 10, Mac, IOS).
    I would appreciate any input that would help me explain this problem which only happens with Hololens.

    Attached is a graph demonstrating the increasing round-trip time and message losses of the 2000 messages being sent.

Sign In or Register to comment.