2019 SDN阅读作业(2) CWC

　　　The answer is based on the paper given by my teacher, Miss Zhu.

　　　The Chinese version of questions is: 

1.过去20年中可编程网络的发展可以分为几个阶段？每个阶段的贡献是什么？

2.网络虚拟化与SDN的关系？

1. How to divide the development of programmable network into different phases over the last 20 years? What are contributions at each phase?

　　(1) active networks (from the mid-1990s to the early 2000s)

　　• introduced programmable functions in the network to enable greater to innovation;

　　• Programmable functions in the network to lower the barrier to innovation;

　　• Network virtualization, and the ability to demultiplex to software programs based on packet headers；;

　　• The vision of a unified architecture for middlebox orchestration.

 

　　(2) control and data plane separation (from around 2001 to 2007)

　　• developed open interfaces between the control and data planes;

　　• Logically centralized control using an open interface to the data plane;

　　• Distributed state management;

 

　　(3) the OpenFlow API and network operating systems (from 2007 to around 2010)

　　• represented the first instance of widespread adoption of an open interface and developed ways to make control-data plane separation scalable and practical.

　　• Generalizing network devices and functions

　　• The vision of a network operating system

　　• Distributed state management techniques

 

2. What is the relationship between network virtualization and SDN?

　　• SDN as an enabling technology for network virtualization

　　• Network virtualization for evaluating and testing SDNs

　　• Virtualizing (“slicing”) an SDN

 

 

来源：https://www.cnblogs.com/willofficial/p/11964835.html