Some understanding before you formally study SDN

Software-defined networks (software Defined Network, SDN), a new network innovation architecture of Emulex Network, is a way of realizing network virtualization, and its core technology openflow by separating the control surface of network equipment from the data plane. Thus, the flexible control of network traffic is realized, so that the network becomes more intelligent as a pipeline.

Note: Network Function Virtualization Industry Alliance (Networks Functions VIRTUALISATION,NFV)

SDN Advantages of:

Networks in traditional it architectures, when deployed on-line according to business requirements, it is tedious to re-modify the configuration on the corresponding network devices (routers, switches, firewalls) if business requirements change. In the rapidly changing business environment of the internet/Mobile Internet, the high stability and high performance of the network are not enough to meet business requirements, but flexibility and agility are even more critical. What SDN does is to isolate the control on the network device, which is managed by a centralized controller, without relying on the underlying network devices (routers, switches, firewalls), and shielding the differences from the underlying network devices. While control is completely open, users can customize any network routing and transport rules policies that they want to implement, making them more flexible and intelligent.

After the SDN transformation, the routers of each node in the network need not be configured repeatedly, and the devices in the network are automatically connected. You only need to define simple network rules when you use them. If you don't like the router's own built-in protocol, you can modify it programmatically to achieve better data exchange performance.

If there are several services in the network, such as SIP, FTP, streaming media, the total bandwidth of the network is certain, then if some time the streaming media service needs more bandwidth and traffic, it is difficult to deal with in the traditional network, it is easy to implement in the network after SDN transformation, SDN can make traffic shaping, regular, temporarily let the streaming media "pipeline "Thicker, let the streaming media more bandwidth, even shut down the SIP and FTP" pipeline ", to reduce the demand for streaming media to restore the original bandwidth.

Because of the openness of the business logic, the network as the development space of "pipeline" becomes infinite possibility. If the business application model for future cloud computing can be simplified to "cloud-to-tube-to-end", then SDN is an important technical support for the "pipe" loop.

SDN Networks vs Traditional networks

Some understanding before you formally study SDN