1. Tinkernet Students: Dan Turner, Mark Kegel, Erik Shimshock and Ryan Ausanka-Crues Faculty: Titus Winters, Mike Erlinger

2. Project Overview Who we are  Harvey Mudd College & University California Riverside What is Tinkernet?  System to allow students to write the networking code of an OS Why would you want it?  Provides a convenient and controlled environment to write and test networking code

3. Who we are: Harvey Mudd College - small Science and Engr College - 700 students; 100 Computer Science Majors University California Riverside - large state university - 15000 students, 1000 Computer Science and Computer Engr majors

4. What is Tinkernet? Stand alone environment to provide a laboratory for computer networking experiments. Cheap and Easy to build and to maintain

5. Tinkernet: Operational Overview Students work on a Server where they develop networking code that is then linked into a OS kernel. This kernel is then download to a machine and executed. Students can then exercise their code and evaluate the performance of their networking code.

6. Tinkernet Hardware

8. Software: Beginning

9. Behind the Scenes: Compiling the Kernel OSKit  provides a fully operable kernel  we strip out the networking module  student code gets compiled in as the new networking module  then you have your kernel...

10. Behind the Scenes: Booting the Kernel tinkercontroller  is a daemon that manages the nodes  a free node is chosen, and the kernel is sent to it  if all has gone well, you have a running kernel

11. Behind the Scenes:

12. Student Assignments Writing modules to handle the protocol stack  ethernet, IP, UDP, ARP  TCP - could do but is a lot of work  Scaled down version of TCP  Study created protocols: discovery  ?

13. How it works... SSH Tinkerbell Students Nodes TFTP

14. The Student Perspective (1) Student writes code (2) Student compiles code into kernel (3) Student uses tinkerboot to load kernel : Tinkerboot (4) Student tests kernel: netprintf (5) Kernel dies, and student repeats the first four steps

15. Software: Student Boots Kernel

16. The Student Perspective

17. Software: Student Tests Kernel

18. The Running Kernel Kernels are expected to respond to:  ARP requests  IP broadcast  Handle IP packets  Also UDP  Also need to be able to generate their own packets

19. Controlling the Kernel Each node has two network cards Is hooked in to two separate networks: warzone and admin Student packets are sent over warzone Admin network handles management of each node - booting, restarting, debug

20. Software Interaction

21. Why this approach? Mini Emulab - but we wanted control, I.e. 24 hour availability Tinkernet development is a good learning environment for OS/Systems Oskit - probably a bad choice…future Linux Need to add more labs

22. Tinkernet in the classroom Lectures discuss the back material of the various protocols (Computer Networks by Peterson & Davie Each Lab has a write-up of: background, tasks and questions Students work together for 2 hours in a dedicate terminal room - uncover issues in lab description, etc. Thereafter they are on their own

23. Tinkernet in the classroom, cont. Students create a web page (restricted login) that includes:  Discussion of lab - issues uncover, things not understood, time taken, etc.  Source code (in C)  Exchange of network messages (Ethereal)  Answers to questions

24. Tinkernet in the classroom, cont. Assessment  Plan to ask questions before the course and before and after each lab.  Still to be done

25. Things left to do... Documentation…Twiki is up. We will make changes in the Spring http://tinkernet.cs.hmc.edu:8080/wiki/inde x.php/Main_page Currently Package for Distribution. Looking for others interested in using Develop assessment materials

26. Questions ?