Using Real Applications in a Simulated Network - Showcase

[adamgeorge309]

Discuss the "Using Real Applications in a Simulated Network" showcase here. Ideas and recommendations are welcome.

[yan711]

Hi Adam,

I am a beginner of using OMNET++ as well as INET. I am following this showcase to run real applications in a simulated network. However, i met two errors and the packet cannot be transported by the router to tapb. The first one is "Transport prototol UDP is not connected", then i added "*.router.hasUDP = true" in the .ini, and the problem was solved. The second one is "No socket registered on port 4004", and i have no idea how to solve it. Isn't "vlc rtp://192.168.3.20:4004 &" supposed to bind the socket on the port 4004?
Do you know how to solve this issue?
Btw, i am using OMNET++5.5.1 and INET 4.2.0.
Thanks in advance!

[adamgeorge309]

Can you try it with the omnetpp master branch and INET 4.2? Also, the video file in the script is not in the repo for now, so use another one and replace the filename in the script. Thanks for reporting this.

[yan711]

Thank you for your answer! I installed omnetpp master branch with a failure, so I tried with OMNeT++5.6.2 and 5.6.1 with INET 4.2. The same two errors occured. And I wrote a udp socket which is binded on "192.168.3.20" and port 4004 in real application, and got the same errors.
Do you know what might cause this error?

[AAGiron]

Hi,

I'm executing OMNET 6.0 and INET 4.4. First I've got a syntax error in *.router.ipv4.natTable.config, fixed by escaping an '&'. Then, when I run it returns:
<!> Error: Gate VideostreamingShowcaseNetwork.host1.eth[0].mac.upperLayerIn is not connected to a module of type queueing::IPacketQueue -- in module (inet::EthernetMac) VideostreamingShowcaseNetwork.host1.eth[0].mac (id=206), during network initialization

Any suggestion?

Thanks in advance

[AAGiron]

Hi,

For some reason, using 'setcap' didn't work for me, but I fixed it by executing inet as root user (modifying run.sh script).

[faheemkhuhawar]

How did you resolve this error?

<!> Error: Gate VideoStreamingShowcase.host1.eth[0].mac.upperLayerIn is not connected to a module of type queueing::IPacketQueue -- in module (inet::EthernetMac) VideoStreamingShowcase.host1.eth[0].mac (id=206), during network initialization

And this error,

[00007f1940002580] main filter error: Failed to create video converter

Please guide.

I modified the following lines in omnetpp.ini to be as,

*.router.ipv4.natTable.config = xml("<config> \
                                        <entry type='prerouting' \
                                        packetFilter='has(Ipv4Header) Ipv4Header.destAddress == \"192.168.2.99\"' \
                                        srcAddress='192.168.3.99' destAddress='192.168.3.20'/> \
                                     </config>")

[adamgeorge309]

This error is resolved in the master branch.

[tortoiseme]

Hi,

I am getting this error: main filter error: Failed to create video converter. How did you resolve it, please?

[chivas1000]

@adamgeorge309
Hi, I'm using ubuntu18.04 and want to try this videostreaming case, because of the ubuntu version I installed omnetpp 5.6.2 and INET 4.2.5 since only this can run properly, but in the INET github repository I didn't find any videosteaming case in TAG before INET4.3.0.

I copied the videostreaming showcase in my INET tried to run it and failed too.

would you mind tell me which would be the right version of omnetpp and INET for ubuntu18.04 or is there any ways to run this in 18.04?

Thanks.

[xingyeLiu123]

Hi, I am wondering why vlc puts its data stream into Router's IP(192.168.2.99) rather than Tapa's IP(192.168.2.20)? When I use a socket to send some UDP packets to the Tapa's IP(192.168.2.20), the emulation network could not recognize these packets, however, when I change the destination IP to 192.168.2.99, the emulation network received these UDP packets.

[xingyeLiu123]

Supplementary explanation: StandardHost module contains ExtUpperEthernetInterface and I have already bind these StandardHost modules with different TAP devices(i.e. tapa, tapc) through their device(string) parameter.

[adamgeorge309]

To address the first question, if the packets are sent to 192.168.3.20 (the destination), the packets wouldn't go through the simulated network, but would be sent via the loopback interface. So the packets are sent to the router's interface, where the destination address is rewritten to 192.168.3.20.

[adamgeorge309]

To the second question, can you be more specific about what you did? It should be possible to add other hosts/tap interfaces.

[xingyeLiu123]

Thanks for your reply！Here is what I have done: I have tried to create 6 sockets for transmitting emulation, which are treated as real applications, and I have bound these 6 sockets with socket.bind() function to 6 TAP devices through IP address. Then, I have created 6 StandardHost modules in simulated network, and each of them is bound with a TAP device using "*.hostx.eth[0].device = "tapx". Here is what I want to do: I want these StandardHost with ExtUpperEthernetInterface(contains TAP device) to represent the above 6 real applications(sockets) in simulated network. And the "Mapping Relationship" between the real socket applications and the StandardHost modules is achieved by using socket.sendto(UDP data,"tapx's IP address") function. Then, the UDP packets can enter the simulated network through above mentioned "Mapping Relationship". Moreover, the transmission between these real socket applications can be simulated in OMNeT++, thus achieving performance statistics. To summarize, the original transmission between real applications is Socket1-->Socket2, I am trying to change it to Socket1(Real)-->Tap1(StandardHost1)(Simulated)-->Router(Simulated)-->Tap2(StandardHost2)(Simulated)-->Socket2(Real) by using emluation. Can you provide some suggestions? If you have any question about my statement, please point it out. Thank you very much!

[xingyeLiu123]

In a word, I am wondering whether the StandardHost module can receive the UDP packets form a real application through TAP device rather than the Router module, and further achieving packet transmission in simulated network.