This document discusses Software Defined Networking (SDN) and its implications for network security, emphasizing the need to protect the SDN control environment. It highlights the advantages of SDN, such as programmable configuration and flexible data flow control, while also addressing potential security vulnerabilities that arise from the separation of data and control planes. Various case studies illustrate the application of SDN in real-world scenarios alongside the security challenges faced by traditional architecture networks.

1. SDN: is it a solution for
network security?
Smelyanskiy R.L.
Moscow State University, Computer Systems Laboratory
Applied Research Center for Computer Network
2013

2. Agenda
• What is SDN network?
• Term “protecting” could be many-sided…
• SDN control environment also needs to be
protected.
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3. Software defined evolution
RIP
VLAN
OSPF
IS-IS
Classic router
…
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ACL
MPLS
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4. Software defined evolution
RIP
VLAN
OSPF
IS-IS
Classic router
…
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ACL
MPLS
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5. Software defined evolution
RIP
VLAN
OSPF
IS-IS
Classic router
…
25.11.2013
ACL
MPLS
prof.R.Smelyanskiy MSU & ARCCN
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6. Software defined evolution
VLAN
Flow Table
TCAM
Controller
Switch
RIP
OSPF
IS-IS
ACL
MPLS
…
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7. Software defined evolution
Flow Table
MAC
src
MAC
dst
TCAM
*
*
IP
IP
Flow Table Dst
Src
*
Switch
5.6.7.8
TCP
sport
*
TCP
dport
Action
* Controller
port 1
RIP
OSPF
Routing
Rule examples
IS-IS
*
00:1f:..
*
*
*
*
port 5
*
*
*
*
*
22
drop
20
666
port 7
00:20.. 00:1f:.. 1.2.3.4 5.6.7.8
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VLAN
prof.R.Smelyanskiy MSU & ARCCN
ACL
Switching
MPLS
Firewall
…
Flow
Switching
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8. Software defined evolution
Flow Table
MAC
src
MAC
dst
TCAM
*
*
IP
IP
Flow Table Dst
Src
*
Switch
5.6.7.8
TCP
sport
*
TCP
dport
Action
* Controller
port 1
RIP
OSPF
Routing
Rule examples
IS-IS
*
00:1f:..
*
*
*
*
port 5
*
*
*
*
*
22
drop
20
666
port 7
00:20.. 00:1f:.. 1.2.3.4 5.6.7.8
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VLAN
prof.R.Smelyanskiy MSU & ARCCN
ACL
Switching
MPLS
Firewall
…
Flow
Switching
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9. Flow Table
TCAM
Network operating system
Software defined evolution
Controller
Switch
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APP
VLAN
APP
RIP
APP
OSPF
APP
IS-IS
APP
ACL
APP
MPLS
APP
…
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10. Software defined evolution
Network operating system
Switch
Controller
Switch
APP
VLAN
APP
RIP
APP
OSPF
APP
IS-IS
APP
ACL
APP
MPLS
APP
…
Switch
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11. Software defined evolution
Advantages devices
Cheep and simple switch
Flexible for configuration
APP
VLAN
Network Global View
Free for innovation
Network operating system
Switch
Controller
Switch
APP
RIP
APP
OSPF
APP
IS-IS
APP
ACL
APP
MPLS
APP
…
Switch
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12. Software defined evolution
Advantages
Cheep and simple network devices
Flexible for configuration
Globalfor innovation
Network View
Free
Network operating system
Switch
Controller
Switch
APP
VLAN
APP
RIP
APP
OSPF
APP
IS-IS
APP
ACL
APP
MPLS
APP
…
Switch
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13. Case studies
• Large Transit Service Provider
• Big International Company
– Multiple offices
– VPN communications
• Network of Large Organization
– Large internal networks
– Various types of network activities
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14. Security in traditional architecture
networks
• Case studies:
– Large Transit Service
Provider
– Airport network
– ISP (VPN provider)
• Tendencies
– Traffic growth
– Mobility
• Infrastructure
• Software
• Protocols
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15. Term “protecting” could be manysided…
Physical access
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16. Airport example
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17. Airport example
Control
process
Control
process
Control
process
Control
process
Control
process
trespasser
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Control
process
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18. Airport example
Control
process
Control
process
Control
process
Malware
Control
Control
process
process
Control
process
trespasser
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Control
process
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19. Airport example
Control
Packet
forwarding
process
Control
Packet
forwarding
process
Control
Packet
forwarding
process
Control
Packet
forwarding
process
Control
Packet
forwarding
process
Control
process
trespasser
SDN
Controller
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20. Term “protecting” could be manysided…
Network flow control
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21. Network of Organization example
Tenant A
Tenant
app
Tenant B
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22. Network of Organization example
Traffic
Dst point
Traffic
Src point
Tenant AAccept
Drop
Tenant
app
Tenant B
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Traffic
Dst point
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23. Network of Organization example
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24. Network of Organization example
Traffic
Src point
Firewall
rules
Firewall
app
Firewall
rules
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Traffic
Dst point
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25. SDN control
environment also needs
to be protected.
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26. SDN control environment security
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27. Controller security app
Malware
traffic
Legal
traffic
OF event
OF event
OF event
OF event
Security
app
Security
app
OF event
OF event
OF event
OF event
Legal
traffic
Legal
traffic
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Malware
traffic
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28. Switch-controller security
Malware
Switch
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29. Switch-controller security
Internet Key
Exchange, IPsec, Kerb
eros and etc.
Authentication
server
Malware
Switch
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30. Controller-to-controller security
Seems to be secure
enough,
but an expensive
solution
Controller-to-controller
out-band protocol
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31. Controller-to-controller security
Problem 1
Check
policies
Problem 2
Isolate
Controllers traffic
and
Datapath traffic
Controller-to-controller
in-band protocol
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Problem 3
Special
QoS
settings
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32. Controllers requirements
• c-applications should be reusable by different controllers placed
near-by each other;
• different controller instances should be able to share the same
instance of a c-application;
• controller should be trusted environment;
• controller should be scalable; it means that if workload is
growing beyond the current computational power of controller
then it should be able to get more computational power, for
example by splitting its activity with another controller
instance, placed on another physical resource;
• if some controller instance shut down than some other
controllers placed nearby should be able to catch up those part
of network switches were managed by those shut down.
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ARCCN
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33. Conclusion
• Software Defined Networking (SDN) has been
rapidly developed.
– Working in data centers
– Replacing proprietary routers
• Splitting data plane and control plane brings
advantages, but also opens new way to exploit
such networks in malicious purposes.
The major advantages of SDN approach
– programmable configuration
– data plane and control plane separation
– flexible data flow control
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34. Q&A
smel@.cs.msu.su
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35. Switch - Controller security
Control channel
Openflow switch
Openflow event
Openflow event
host
Legal
traffic
host
host
Controller
host
Malware
traffic
Openflow
event checker
Openflow event
Openflow event
Openflow event
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Openflow event
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36. Switch - Controller security
Control channel
Openflow switch
Openflow event
Openflow event
host
Legal
traffic
host
host
Controller
host
Malware
traffic
Openflow
event checker
Openflow event
Openflow event
Openflow event
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Openflow event
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37. Switch - Controller security
Control channel
Openflow switch
Openflow event
Openflow event
host
Legal
traffic
host
host
Controller
host
Malware
traffic
Vulnerable
app
Openflow event
Openflow event
Openflow event
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Openflow event
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38. Switch - Controller security
Control channel
Openflow switch
Openflow event
Openflow event
host
Legal
traffic
host
host
Controller
host
Malware
traffic
Vulnerable
Security
app
Openflow event
Openflow event
Openflow event
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Openflow event
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39. Controller-controller protocol
security
Control channel
Controller-controller
Openflow switch
out-band protocol
Seems to be secure
enough,
but an expensive
solution
host
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host
host
host
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Controller
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40. Controller-controller protocol
security
Check
policies
Isolate
Controllers traffic
and
Datapath traffic
Special
QoS
settings
Openflow switch
host
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host
host
Controller
Controller-controller Controller-controller
in-band protocol out-band protocol
host
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Controller
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