Slides from a live demo at the Linux Foundation OpenDaylight summit.

1. “You can keep your firewall (if you
want to)”
Practical, simple and cost saving applications of OpenDaylight
you can implement today
John Sobanski, Engineer, Solers Inc.
July 2015
@OpenDaylightSDN #OpenSDN

2. What You Will Learn today (By Demonstration)
• 10,000 Foot Views of Software Defined Networking (SDN), OpenDaylight (ODL) and Service Function Chains
(SFC)
• Solve real world data center problems with ODL
• RESTCONF API
• ODL Service Function Chaining
• Feel free to contact me for any details I don't cover here
jsobanski@solers.com
https://ask.opendaylight.org/users/420/runamuck/
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3. Top three emerging technologies of the decade?
• My take…
• Big Data
• DevOps
• Software Defined Networks
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Any Others?

4. “Is SDN Hype?”
• “Big Data and DevOps have clear applications and use cases but Software Defined Networks appears to be a
solution in search of a problem.”
• “Most SDN activity is focused in Academia or dedicated ‘Network Function Virtualization (NFV)’ shops... not
relevant to us.”
• "SDN/ NFV only applies to Greenfield Architectures."
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These slides will prove these opinions wrong

5. “Who cares about networks?”
• Answer: You Do! Network latency and/ or loss breaks services.
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6. “Latency and Loss doesn’t apply to my Data Center”
• “Latency and Loss? I've got dozens of 10GbE ports!!!”
• Layer 2: Spanning tree protocol
• Blocks all but one path to prevent loops
• (Enable LACP/ LAG)
• Layer 3: Shortest path first
• Sends all traffic through a congested "one hop" path over a wide open "two hop" path
• (Try Traffic Engineering)
• Layer 4: Default TCP buffers
• Small buffers mean more round trips. Latency throttles throughput.
• (Tune the buffer)
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You need to care about the network!

7. What are Network Services?
• Familiar Network Services
• Load Balancing
• Firewall
• Deep Packet Inspection (DPI)
• Access Control Lists
• Parental Control
• Other Network Services
• "Global State" (Routing)
• Broadcast Domain Scoping (VLAN)
• Resource Signaling
• Prioritization and Preemption
• Multicast
• N-Cast
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8. 10,000 Foot Overview
• 10,000 Foot view of SDN
• At any give time, use a centralized controller to move data through your network equipment as you see fit
• Doesn't seem like a big deal to non-network types but this is incredibly powerful!
• 10,000 Foot view of OpenDaylight
• Allows you to install network services as "Apps"
• Provides a single REST API to configure heterogeneous hardware
• This is a “no brainer” for developers but is HUGE for network engineers
• 10,000 Foot view of Service Function Chains
• “Service Overlay”
• Divorce Network Services From Topology
• For more detail see:
• https://www.opennetworking.org/sdn-resources/sdn-definition
• http://www.opendaylight.org/project/technical-overview
• https://wiki.opendaylight.org/view/Service_Function_Chaining:Main 8

9. A Little More Detail: SDN Layers
• Top Layer  Northbound
• Network Apps & Orchestration
• Business logic to monitor and control network behavior
• Thread services together
• Middle Layer  Controller Platform
• Exposes "Northbound" APIs to the Application layer
• Lower Layer  Southbound
• Command and control of hardware
• Network Devices (Physical or Virtual)
• Switches, Routers, Firewalls etc.
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10. A Little More Detail: OpenDaylight
• OpenDaylight
• Open source project
• Modular/ Pluggable and flexible controller platform
• Java Virtual Machine (JVM)
• Dynamically Pluggable Modules for Network Tasks
• OSGi framework (local applications)/ bidirectional REST (local or remote) for the northbound API
• Network Apps
• House business logic and algorithms
• Gather network intelligence from the controler
• Run algorithms to perform analytics
• Orchestrate new rules (if any) via controller
• Southbound
• OpenFlow 1.3, OVSDB, SNMP, CLI
• Service Abstraction Layer links Northbound to Southbound
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11. A Little More Detail: ODL
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12. A Little More Detail: SFC
• SFC enables a “service topology”
• Overlay built “on top” of existing network topology
• Use any overlay or underlay technology to create service paths
• VLAN, ECMP, GRE, VXLAN, etc.
• SFC provides resources for consumption
• Service Topology connects those resources
• Quickly/ Easily add new service functions
• Requires no underlying network changes
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13. One Caveat Before we begin
• WARNING: Software Defined Networking is incredibly powerful!
• You must protect your Southbound interfaces with the same regard as a firewall or any root privileges
• ODL accommodates TLS for Southbound interfaces
• The security, identity and bureaucratic planes are orthogonal to the technology plane we discuss here
• We do not discuss security, identity or policy but you must consider them when architecting your ODL
solution
13

14. One more Caveat
• WARNING: If you are not a hands-on network engineer, this presentation may "spoil" you.
• To provide the following two OPSCON using legacy protocols may be impossible and at the very least requires intense,
disciplined, meticulous network engineering.
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15. DPI Bypass
Approach #1: RESTCONF API
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16. OPSCON #1: Deep Packet Inspection Bypass
• This scenario investigates how to reduce latency
• You have a data center that performs deep packet inspection (DPI) for inter-network flows
• DPI injects latency into the end to end (E2E) flow and increases Round Trip Time (RTT)
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Reminder: Network latency and loss breaks services!

17. Topology
• Network gateways in Firewall/ DPI appliance
• VLAN steer (bent pipe) traffic through DPI (via gateways) for inter-network flows
• Can we create logic to DPI only once?
17

18. One Approach
• Put logic (i.e. rules) in the DPI appliance to bypass certain flows
• This, however consumes resources and can saturate the backplane
18
Put logic here?

19. Better Approach
• Use the OpenDaylight controller and put logic in the switch!
19
Put logic here!

20. OPSCON #1 Detailed Topology
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21. DPI Bypass Demo
Approach #1: RESTCONF API
Note: This section will be a live demonstration
21

22. Step 1: Start ODL Platform via Client
• Platform includes controller
• Install Network Apps via command line
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23. Validate Topology
• Connect to controller and “pingall”
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24. ODL Shows the Layer 2 Interfaces
24

25. Baseline: Two DPI = Severe Latency
• Ping from Client (h1) to Server (h3) shows 40+ ms latency
mininet> h1 ping h3 PING 10.0.3.101 (10.0.3.101) 56(84) bytes of data.
64 bytes from 10.0.3.101: icmp_seq=1 ttl=62 time=42.1 ms
64 bytes from 10.0.3.101: icmp_seq=2 ttl=62 time=41.3 ms
64 bytes from 10.0.3.101: icmp_seq=3 ttl=62 time=41.1 ms
^C
--- 10.0.3.101 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2003ms
rtt min/avg/max/mdev = 41.119/41.546/42.143/0.465 ms
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26. Baseline: End to End (E2E) Path
• Traceroute shows a path through the two DPI gateways, as expected
mininet> h1 traceroute -n h3
traceroute to 10.0.3.101 (10.0.3.101), 30 hops max, 60 byte packets
1 10.0.1.1 21.180 ms 21.028 ms 20.837 ms
2 10.0.2.1 42.565 ms 42.482 ms 42.418 ms
3 * * 10.0.3.101 43.144 ms
mininet>
26

27. Configure Switch via ODL Platform REST API
27

28. Configure Switch via ODL Platform REST API
• Use these headers:
Accept: application/xml
Authorization: Basic YWRtaW46YWRtaW4=
• Then post the following flows (next slide) to Switch 2's table zero:
PUT flow with ID 202 to
http://<controller_ip>:8181/restconf/config/opendaylight-
inventory:nodes/node/openflow:2/table/0/flow/202
PUT flow with ID 303 to
http://<controller_ip>:8181/restconf/config/opendaylight-
inventory:nodes/node/openflow:2/table/0/flow/303
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29. RESTCONF Flows (XML)
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30. The Switch Accepts the Flows
$ sudo ovs-ofctl -O OpenFlow13 dump-flows s2
cookie=0x0, duration=350.260s, table=0, n_packets=0, n_bytes=0,
priority=200,ip,nw_dst=10.0.3.101 actions=set_field:f6:2f:25:06:ab:27-
>eth_dst,output:4
cookie=0x1, duration=33.552s, table=0, n_packets=0, n_bytes=0,
priority=200,ip,nw_dst=10.0.1.101 actions=set_field:f2:3e:8d:a4:71:07-
>eth_dst,output:5
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31. Latency Reduced
• Ping now shows that the second, slow DPI is no longer in the path:
mininet> h1 ping h3
PING 10.0.3.101 (10.0.3.101) 56(84) bytes of data.
64 bytes from 10.0.3.101: icmp_seq=1 ttl=63 time=21.3 ms
64 bytes from 10.0.3.101: icmp_seq=2 ttl=63 time=20.9 ms
64 bytes from 10.0.3.101: icmp_seq=3 ttl=63 time=20.7 ms
^C
--- 10.0.3.101 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2002ms
rtt min/avg/max/mdev = 20.713/20.983/21.320/0.252 ms
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32. Latency Reduced
• Traceroute Confirms that the flow bypasses the second DPI
mininet> h1 traceroute -n h3
traceroute to 10.0.3.101 (10.0.3.101), 30 hops max, 60 byte packets
1 10.0.1.1 21.117 ms 20.796 ms 20.423 ms
2 10.0.3.101 24.597 ms 24.477 ms *
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33. DPI Bypass Demo
Approach #2: ODL SFC
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34. A Little More Detail: ODL
ODL Provides a Northbound SFC “App”
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35. SFC Approach: Create a “Service Overlay”
• 1. Register Firewalls in service pool
• “Service Functions”
• 2. Configure switches to forward
packets based on controller logic
• “Service Function Forwarders”
• 3. Configure SFC Logic
• … Next Slide
#ODSummit
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2
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36. SFC Workflow (Highly Abstracted!)
• Register (Previous Slide)
• Service Functions (Appliances) -- AKA Network Services
• Service Function Forwarders (ODL SFC Controlled Switches)
• Create Service Function “Chains”
• “Chain” of Network Services
• I.e. First Firewall, then Apply Parental Control, then Virus Scan etc.
• Create Service Function Paths and Rendered Service Paths
• Selects path through actual appliance (SF) instances e.g.
• RSP-1 = Firewall-1, Parental-Control-1, Virus-Scan-1
• RSP-7 = Firewall-3, Patental-Control-1, Virus-Scan-2
• Create “Classifier”
• Apply SFC to flows
#ODSummit

37. DPI Bypass Demo
Approach #2: ODL SFC
Note: This will be a live demo
37
Based on: https://lists.opendaylight.org/pipermail/sfc-dev/2015-July/001408.html
by Brady Johnson and Ricardo Noriega at Ericsson.com

38. Baseline
• No Flows in Switch, No Objects in GUI
#ODSummit

39. Configure via REST API
• Add SF, SFF, SFC, SFP and RSP
• GUI Populated
• Controller then injects logic into SFF via
flows
$ sudo ovs-ofctl dump-flows
sff1 -OOpenFlow13
#ODSummit

40. Test 1: Configure Classifier to Use RSP-1
tcpdump shows WGET goes
through both service functions
Total time: 0.341 seconds
#ODSummit
SFF-1 Traffic SFF-2 Traffic

41. Test 2: Configure Classifier to Use RSP-3
tcpdump shows WGET goes
through only one service
functions
Total time: 0.178 seconds
#ODSummit
SFF-1: No
Traffic
SFF-2 Traffic

42. Backup Slides
#ODSummit

43. #ODSummit
OPSCON #2:
Egress Bypass

44. OPSCON #2: Bypass DPI on Egress
• Scenario: You have a product distribution system where Egress throughput >> Ingress throughput.
• You perform Deep Packet Inspection on flows between External (EXT) hosts and your Demilitarized Zone
(DMZ) Proxies.
44

45. Topology
• You implement a DPI "router on a stick," to ensure Inter-network communications pass through the DPI.
• A switch bent pipes the traffic at layer 2
45

46. Scenario
• The Egress traffic will increase past the capacity of the DPI appliance
• You realize that there are cheaper methods of securing your egress flows then upgrading
to a bigger DPI appliance…
46

47. Egress Security
• With egress flows you want to ensure that return/ ACK traffic does not include exploits and that egress flows do not
facilitate zombies or phone home exploits.
• Some ideas:
• Ensure only approved ports
• Access Control Lists
• iptables
• Host firewalls
• Mitigate against malicious code over approved ports:
• HIDS on Servers
• Uni-directional bulk data push with Error Detection and Correction over one way fiber
• TLS with x509 certs
47

48. Trade Solutions
• END GOAL: You want to have DPI inspection on ingress flows, but not egress, since the other security
measures will cover the egress flows.
• One approach is to put logic on your DPI appliance to say "don't scan egress flows," but that wastes
capacity/ resources and could saturate the backplane
• An approach with legacy Network protocols is very difficult to implement and results in asymmetric
routes (will break things)
• Using OpenDaylight, we have a simple solution that only requires matches/ actions on six (6) flows
48

49. The Goal
• When EXT initiates, pass through DPI
• When DMZ initiates:
• Bypass DPI on PUT (Egress)
• Scan on GET (Ingress)
49

50. Detailed Diagram
1. ACL
2. Scan all EXT  DMZ
3. Bypass DMZ PUT
4. Scan DMZ GET
50

51. OpenFlow Logic
1. ACL only allows permitted flows
2. For Ingress ( EXT-> DMZ ) flows, allow normal path to virus scan via gateway
3. For Egress ( DMZ -> EXT ) PUT flows, intercept packet
1. Change destination MAC from Gateway to EXT
2. Change destination Port from Gateway to EXT
3. Decrement TTL by one
4. For Egress (DMZ -> EXT) GET flows (Treat as ingress)
1. DMZ uses dummy IP for EXT server
2. Switch intercepts packet
3. Switch changes source IP to dummy DMZ address
4. Switch changes dest IP to correct EXT IP
5. Packet continues on its way to gateway
6. Reverse logic for return traffic
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52. OPSCON #2 Topology
52

53. OPSCON #2
Note: This will be a real time demo
53

54. Setup
• As before, start ODL, connect switch to controller and “pingall”
54

55. ODL Shows Connected L2 Interfaces
55

56. Baseline: Push a file from DMZ to EXT
mininet> dmz curl http://10.0.1.102 --upload-file test.txt
• EXT Server Shows Successful PUT
10.0.2.101 - - [10/Jul/2015 14:50:22] "PUT /test.txt HTTP/1.1"
• TCPDUMP on firewall shows egress scan traffic (as expected)
56

57. Install the Flows via RESTCONF API
• Either via POSTMAN or CURL
curl -v -H "Content-Type: application/xml" -X PUT --data "@fw_demo_404.xml" -u admin:admin
http://localhost:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:3/table/0/flow/404 2>&1 | grep HTTP/1.1
curl -v -H "Content-Type: application/xml" -X PUT --data "@fw_demo_505.xml" -u admin:admin
http://localhost:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:3/table/0/flow/505 2>&1 | grep HTTP/1.1
curl -v -H "Content-Type: application/xml" -X PUT --data "@fw_demo_606.xml" -u admin:admin
http://localhost:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:3/table/0/flow/606 2>&1 | grep HTTP/1.1
curl -v -H "Content-Type: application/xml" -X PUT --data "@fw_demo_707.xml" -u admin:admin
http://localhost:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:3/table/0/flow/707 2>&1 | grep HTTP/1.1
curl -v -H "Content-Type: application/xml" -X PUT --data "@fw_demo_808.xml" -u admin:admin
http://localhost:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:3/table/0/flow/808 2>&1 | grep HTTP/1.1
curl -v -H "Content-Type: application/xml" -X PUT --data "@fw_demo_909.xml" -u admin:admin
http://localhost:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:3/table/0/flow/909 2>&1 | grep HTTP/1.1
57

58. DMZ PUT a file to EXT
mininet> dmz curl http://10.0.1.102 --upload-file test.txt
• The EXT server shows this second, successful put
10.0.2.101 - - [10/Jul/2015 14:50:22] "PUT /test.txt HTTP/1.1" 200 -
10.0.2.101 - - [10/Jul/2015 14:53:05] "PUT /test.txt HTTP/1.1" 200 -
• The firewall TCPDUMP, however does not show additional traffic!
58

59. Plumb Statistics via API
• You can see a Match on the flow through the REST API:
• http://<controller_IP>:8181/restconf/operational/opendaylight-
inventory:nodes/node/openflow:3/table/0/flow/404/flow-statistics/
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60. Test DMZ to EXT GET (Ingress)
• Use a Dummy IP to trigger a flow match.
• The egress port of the switch will NAT it back to the real destination IP.
• We see instant feedback on the Mininet Console
60

61. EXT Server Shows Successful Get
10.0.2.101 - - [10/Jul/2015 14:50:22] "PUT /test.txt
HTTP/1.1" 200 -
10.0.2.101 - - [10/Jul/2015 14:53:05] "PUT /test.txt
HTTP/1.1" 200 -
6.6.6.6 - - [10/Jul/2015 15:01:27] "GET / HTTP/1.1" 200 -
• Note Dummy IP
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62. FW TCPDUMP Shows DMZ to EXT GET Scan
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63. Verify All EXT  DMZ Traffic Scan
• Do PUT and GET
63

64. DMZ Server Log Shows Success for Both
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65. TCPDUMP: All EXT to DMZ traffic scanned
65

66. Thank You
#ODSummit