1. Aug 20 th, 2002 Sigcomm Education Workshop 1 Teaching tools for a network infrastructure teaching lab The Virtual Router and NetFPGA Sigcomm Education Workshop August 20 th, 2002 Nick McKeown Professor of Electrical Engineering and Computer Science, Stanford University nickm@stanford.edu www.stanford.edu/~nickm

2. Aug 20 th, 2002 Sigcomm Education Workshop 2 Outline  Why have a network infrastructure teaching lab  Hardware Platform: NetFPGA  Software Platform: Virtual Router  Demo of Virtual Router (hopefully)

3. Aug 20 th, 2002 Sigcomm Education Workshop 3 Why have a network infrastructure teaching lab  Many of our students go to networking companies:  Software engineers implement network protocols, and  Hardware engineers architect and design switches and routers.  More likely to design a router than a computer.  We had classes on digital system design, computer programming, networking and on packet switch architectures. No lab classes in networking.  Want students to design, implement, deploy and debug their own infrastructure elements: IP routers, Ethernet switches, and elements of their own creation.

4. Aug 20 th, 2002 Sigcomm Education Workshop 4 Platform #1: Hardware Platform NetFPGA

5. Aug 20 th, 2002 Sigcomm Education Workshop 5 Hardware Platform: NetFPGA  What: Circuit board with 8 Ethernet interfaces and user-programmable FPGAs.  How used: Students architect, design and deploy their own hardware in an operational network.  Canonical assignment: Ethernet switch  Other assignments: IP router, firewall, packet mis-sequencer, data transcoder, …  Design flow: Industry standard flow  Verilog -> simulation/verification -> synthesis -> download

6. Aug 20 th, 2002 Sigcomm Education Workshop 6 Hardware Platform: NetFPGA Ethernet Interface #1 Ethernet Interface #2 Ethernet Interface #8 User FPGA User FPGA Controller User memory User program Packet buffers 1 2 8  No CPU  Only interface is via Ethernet  Program FPGA via Ethernet  Reset board remotely

7. Aug 20 th, 2002 Sigcomm Education Workshop 7 Hardware Platform: NetFPGA Ethernet Interface #1 Ethernet Interface #2 Ethernet Interface #8 User FPGA User FPGA User memory Ethernet Interface #1 Ethernet Interface #2 Ethernet Interface #8 User FPGA User FPGA User memory Firewall Campus Network ControllerWeb/ftpAnalyzer

8. Aug 20 th, 2002 Sigcomm Education Workshop 8 Hardware Platform: NetFPGA Status  Prototype: Summer 2002  First classroom use: April 2003  Boards available: Early 2004  Looking for sponsors and alpha-users…

9. Aug 20 th, 2002 Sigcomm Education Workshop 9 Platform #2: Software Platform Virtual Router

10. Aug 20 th, 2002 Sigcomm Education Workshop 10 Software Platform: Virtual Router  Problem: How to have 200 students each build and deploy their own router, without kernel hacking and without their own dedicated machine?  What: PC/Linux-based “Virtual Router Server”; students write user-space “Virtual Router Clients” in C, C++, Java, Perl, …  How used: Students architect, design and deploy their own router in an operational network with their own arbitrary topology.  Canonical assignment: Internet router.  Other assignments: QoS router, lookup algorithms, routing protocols, Firewall, …

11. Aug 20 th, 2002 Sigcomm Education Workshop 11 Software Platform: Virtual Router Student’s view Student’s user-space router Ethernet frames Web/ftp servers Campus Network “Virtual Router Client” 1. Packet arrives destined for web server ‘C’. 2. Student’s code (in C, C++, Java, perl) receives Ethernet packet and must route it to correct interface. A B C D

12. Aug 20 th, 2002 Sigcomm Education Workshop 12 Example assignment March 2002, ~100 BS/MS students  Implement a fully functional IP router, including:  Address lookup (static routing table)  TTL check and decrement  IP checksum check and update  ARP request/reply  ICMP: enough for traceroute and ping to work  Environment:  Students receive/send raw Ethernet packets  Four network interfaces  Written in ANSI C

13. Aug 20 th, 2002 Sigcomm Education Workshop 13 Software Platform: Virtual Router The Virtual Router Server Web/ftp servers Campus Network Firewall PC Linux Instructional machines “Virtual Router Server” VR Client Socket

14. Aug 20 th, 2002 Sigcomm Education Workshop 14 Software Platform: Virtual Router Student’s view VR Client VR Client VR Client VR Client VR Client Arbitrary topology Campus Network Web/ftp servers Each interface has locally unique Ethernet and IP address.

15. Aug 20 th, 2002 Sigcomm Education Workshop 15 Software Platform: Virtual Router Student’s view Topology per student Campus Network Web/ftp servers

16. Aug 20 th, 2002 Sigcomm Education Workshop 16 Software Platform: Virtual Router The Virtual Router Server Web/ftp servers Firewall/ Load-balancer Instructional machines “Virtual Router Server” Classifies incoming packet to determine which student should route the packet. Picks next hop Ethernet DA to reach VR Client. Intercepts specific Ethernet addresses on behalf of VR Clients

17. Aug 20 th, 2002 Sigcomm Education Workshop 17 Software Platform: Virtual Router Status  Prototype V1.0: Summer 2001  First classroom use: March 2002  CS244a at Stanford, Assignment #3, ~100 students  V2.0: Summer 2002  Next classroom use: March 2003  First planned release: Summer 2003  Looking for sponsors and alpha-users…