Why is my Cooja simulator's RPL border router (sky mote) not transmitting packets to the HTTP server via serial communication but the Cooja mote is?

Question

I am new to using the Contiki-NG OS and the Cooja simulator. I was following a tutorial from this link and the steps I followed are:

1. I created an RPL border router mote (sky mote) from the example files of Contiki-NG.
2. I created a few hello-world motes (sky motes) surrounding the RPL border router mote.
3. I used the Cooja simulator's GUI to create a serial socket to the RPL border router. The GUI says that the client is connected.
4. In the directory storing the RPL border router's source code examples/rpl-border-router, I opened a terminal and entered

$ make TARGET=zoul connect-router-cooja

The output of this command does not print that the web server has started.

5. When the simulation is running, this command gives me an IPv6 address of the server. It is my understanding that this is the IPv6 address of the RPL border router. When I ping this router, I get continuous responses from the server.

6. When I ping the hello-world nodes however (child nodes), I don't get any response from the ping.

7. When I type http://[router-address-IPv6], the page does not respond.

8. When I do $ wget http://[router-address-IPv6] it tries 20 times and fails. It gives the error "failed: Protocol error."

9. It is my understanding that when I type in the terminal

$ ls /dev/tty*

I should be able to see multiple serial ports, of which /dev/ttyUSB0 should be one of them if my simulation is running and my border router is connected, but I do not see one.

10. On the Cooja simulator, if I go to Tools > Radio messages however, I see the hello-world packets being transmitted to the border router.
11. When I go to tools/serial-io and entered $ ./tunslip6 I get: ipaddress: Success

I expect to see a webpage on typing http://\[router-address-IPv6\] in the browser. I also expect to see /dev/ttyUSB0 under $ ls /dev/tty*

Update 1: When I repeated the same set of steps but this time using Cooja motes instead of sky motes, I was able to open the website and see the neighbours and routing links. The $ make TARGET=zoul connect-router-cooja command however still does not mention any "web server started" message. $ ls /dev/tty* still does not show any /dev/ttyUSB0 as intended.

What is the reason it works only for the Cooja motes?

Answer 1

The /dev/tty.* will never appear if you run Tmote Sky simulated in COOJA. I would guess that it is borderline that the complete Contiki-NG and webserver fits in Tmote Sky - it could be a part of the issue. But I am not completely sure.