CS 6250 QUIZ 2 20 FULL SOLUTION STUDY
GUIDE
◉ L7 - What are the three phases in the history of SDN?
Answer: 1. Active Networks
2. Control and Data Plane Separation
OpenFlow API and Network Operating Systems
◉ L7 - Summarize each phase in the history of SDN.
Answer: 1. Active Networks - Opened up network control and
allowed for customization of functionality of packets passing
through nodes
There were two types of programming models in active networking.
These models differ based on where the code to execute at the nodes
was carried.
1. Capsule model - carried in-band in data packets
2. Programmable router/switch model - established by out-of-band
mechanisms.
Although the capsule model was most closely related to active
networking, both models have some effect on the current state of
SDNs. By carrying the code in data packets, capsules brought a new
, data- plane functionality across networks. They also used caching to
make code distribution more efficient. Programmable routers made
decision making a job for the network operator.
1. Programmable functions in the network to lower the barrier to
innovation.
2. Network virtualization, and the ability to demultiplex to software
programs based on packet headers.
3. The vision of a unified architecture for middlebox orchestration.
2. Control and Data Plane Separation
Inspired two main innovations:
• Open interface between control and data planes
• Logically centralized control of the network
This phase was different from active networking in several ways:
• It focused on spurring innovation by and for network
administrators rather than end users and researchers.
• It emphasized programmability in the control domain rather than
the data domain.
• It worked towards network-wide visibility and control rather than
device-level configurations.
GUIDE
◉ L7 - What are the three phases in the history of SDN?
Answer: 1. Active Networks
2. Control and Data Plane Separation
OpenFlow API and Network Operating Systems
◉ L7 - Summarize each phase in the history of SDN.
Answer: 1. Active Networks - Opened up network control and
allowed for customization of functionality of packets passing
through nodes
There were two types of programming models in active networking.
These models differ based on where the code to execute at the nodes
was carried.
1. Capsule model - carried in-band in data packets
2. Programmable router/switch model - established by out-of-band
mechanisms.
Although the capsule model was most closely related to active
networking, both models have some effect on the current state of
SDNs. By carrying the code in data packets, capsules brought a new
, data- plane functionality across networks. They also used caching to
make code distribution more efficient. Programmable routers made
decision making a job for the network operator.
1. Programmable functions in the network to lower the barrier to
innovation.
2. Network virtualization, and the ability to demultiplex to software
programs based on packet headers.
3. The vision of a unified architecture for middlebox orchestration.
2. Control and Data Plane Separation
Inspired two main innovations:
• Open interface between control and data planes
• Logically centralized control of the network
This phase was different from active networking in several ways:
• It focused on spurring innovation by and for network
administrators rather than end users and researchers.
• It emphasized programmability in the control domain rather than
the data domain.
• It worked towards network-wide visibility and control rather than
device-level configurations.
