RTPS packages are not coming through wi-fi network

[KiriakosD]

Hi,

I am using a simple setup (similar to the Messenger example) of a publisher and a subscriber running in two different computers connected to the same wi-fi network.
I am trying to make them detect each other via RTPS, but it seems that the RTPS packages are not coming through (I am using wireshark to see the network traffic).

The rtps.ini that I use in both cases looks like this:

DCPSDefaultDiscovery=DEFAULT_RTPS
DCPSGlobalTransportConfig=$file

[transport/the_rtps_transport]
transport_type=rtps_udp

Is there something obviously wrong in my setup?
In my last effort one machine was running Linux and the other was running Windows.
Is that a common problem and/or perhaps something that need to configure in my router?

Additional information:

1. I can see the outgoing RTPS messages from both the publisher and the subscriber.
2. When I run both the publisher and the subscriber in the same machine, they detect each other and exchange messages with out any problem.

[simpsont-oci]

Things to check: Is multicast permitted on your WiFi network? Is the outbound multicast SPDP announcement using the wireless interface / IP you'd expect on both machines? If not, you can specify the interface in the config. How many ethernet devices are between the publisher and subscriber? If more than just your router, try increasing the TTL in your configs.

…

On Mon, Mar 30, 2020, 3:29 AM KiriakosD ***@***.***> wrote: Hi, I am using a simple setup (similar to the Messenger example) of a publisher and a subscriber running in two different computers connected to the same wi-fi network. I am trying to make them detect each other via RTPS, but it seems that the RTPS packages are not coming through (I am using wireshark to see the network traffic). The *rtps.ini* that I use in both cases looks like this: `[common] DCPSDefaultDiscovery=DEFAULT_RTPS DCPSGlobalTransportConfig=$file [transport/the_rtps_transport] transport_type=rtps_udp ` Is there something obviously wrong in my setup? In my last effort one machine was running Linux and the other was running Windows. Is that a common problem and/or perhaps something that need to configure in my router? *Additional information*: 1. I can see the outgoing RTPS messages from both the publisher and the subscriber. 2. When I run both the publisher and the subscriber in the same machine, they detect each other and exchange messages with out any problem. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#1609>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AHWIMOYZIQAIB66RS7MHF6TRKBJ5XANCNFSM4LWML7AA> .

[KiriakosD]

Thanks for you reply @simpsont-oci.
Unfortunately I haven't managed to figure the problem out yet.
My router does support multicast and in fact I have realized that the RTPS packages are coming through it correctly when the two computers are connected via Ethernet, but it not via WiFi.

Between the publisher and the subscriber there is only the router.

[simpsont-oci]

Have you tried setting either MulticastInterface or SpdpLocalAddress in the RtpsDiscovery config section?

…

On Tue, Apr 7, 2020, 8:36 PM KiriakosD ***@***.***> wrote: Thanks for you reply @simpsont-oci <https://github.com/simpsont-oci>. Unfortunately I haven't managed to figure the problem out yet. My router does support multicast and in fact I have realized that the RTPS packages are coming through it correctly when the two computers are connected via Ethernet, but it not via WiFi. Between the publisher and the subscriber there is only the router. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#1609 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AHWIMO3Y5UVD7NWGTFKYRLDRLPIIDANCNFSM4LWML7AA> .

[jwillemsen]

Similar question on stackoverflow, see https://stackoverflow.com/questions/61092395/multicast-packages-are-not-passing-through-the-router-when-using-wifi

[KiriakosD]

Thank you both @simpsont-oci and @jwillemsen, an interesting thing I found today is that the RTPS messages are actually coming through when I am using the Multicast address 239.255.255.250:1900 (I changed the default_multicast_group in the RtpsDiscovery.cpp).

Do you think this means that the problem is in my router's configuration?

[jrw972]

I have seen failures where the WAN address of the router came from the same block as the LAN addresses. So yes, it could be your router configuration. Justin

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On Thu, Apr 9, 2020 at 6:25 AM KiriakosD ***@***.***> wrote: Thank you both @simpsont-oci <https://github.com/simpsont-oci> and @jwillemsen <https://github.com/jwillemsen>, an interesting thing I found today is that the RTPS messages are actually coming through when I am using the Multicast address 239.255.255.250:1900 (I changed the default_multicast_group in the RtpsDiscovery.cpp). Do you think this means that the problem is in my router's configuration? — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#1609 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ACKORLY7YH4CUIUFIUSAZFTRLWWDJANCNFSM4LWML7AA> .

-- Justin Wilson Principal Software Engineer Disruptive solutions for a connected world.™ tel (314) 579-0066 objectcomputing.com