How to embed SDN and automation into next-generation cloud data centers

In the era of cloud computing, enterprises need a new data center network architecture. The new network architecture mainly refers to the use of software-defined networks and network automation platforms to build data center network architecture. Dell, which has a well-known hardware manufacturer image, has also made more than 12 billion US dollars in acquisitions in recent years to change its IT image, including a large number of software-defined network products. In this article, let's talk about the significance of SDN and automation in the cloud era.

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Virtual Network Architecture for the Cloud

Virtual network architecture is the cornerstone of a dynamic data center. Adding value and prioritization to applications in the data center is fundamentally about value. Until now, the network design of the data center has been a poorly designed blueprint: it has little to do with the upper layer applications running. With the advent of virtualization, the playing field has now been completely reversed. A correct data center network design must now start with these questions: What do I want to do on the virtualization layer? How should I move virtual machines? How should I deploy applications in virtual machines? How should we plan the network requirements of these applications? In addition, how should I guarantee the distribution time of these applications in the data center, and how can they make the most of the underlying network? Therefore, software-defined networking (SDN) is well suited to dynamically adjust the network above the application layer to best suit the application operation.

To achieve this design, enterprises need to adopt a three-layer architecture, including application and management layers, controllers and switches. The controller becomes another instruction distributor, which is separated from the upper layer. Dell's switches based on the OpenFlow standard integrate all aspects. And Dell believes that it has the opportunity to connect the application layer with the controller and switch.

Combination of Network Virtualization and SDN

CIOs often ask how to combine network virtualization with SDN. With SDN, there is no need to use manual processes or command line interfaces to change network configurations. There is no need to hire professionally trained network engineers. Just hire some developers to integrate the following functions on an automated system: get instructions on the application management level and send it to the controller, without programming on the switch. Suppose you want to transfer a large amount of data between two terminals in the middle of the night. The best way is that the application can initialize a VPN channel with a large bandwidth without any human intervention. So, SDN becomes a way to achieve network programmability in real time based on application needs.

Network integration with OpenStack or CloudStack

OpenStack is a new space. Some people may think that it is not prime time for most customers to run their entire private cloud on OpenStack. However, Dell is very bullish on OpenStack because it allows a lot of innovation using some of the regular open source development ecosystem. Dell participates in many of the extensions of the OpenStack community. Systematically develops modules and plug-ins for networking, servers and storage in the OpenStack architecture. If you are a cloud service provider, you can use Dell storage, servers and networking without relying on VMware or Microsoft hypervisors. Eventually, private cloud customers will be equally suited. OpenStack can become the most effective alternative to it. It may take some time because different customers have different complexity and use cases. So OpenStack is definitely in the high-end space where cloud service providers can find economic value, but for most enterprises, this is still a hypervisor-dominated space.

Are Fabrics Still Needed in SDN?

A few years ago, fabrics were only in the data center. Fabrics were a concept that was supposed to solve all data center network problems, and after fabrics had been around for a while, Dell realized that there were many different customers involved. Customers had different levels of data center problems. Layer 2 end-to-end fabrics have been the go-to technology for companies like Juniper and Brocade. However, they are not only very complex, but the necessity is not as obvious as it was when they were first proposed. More and more Web 2.0 data centers are balancing islands of Layer 2 networks connecting Layer 3 products. The control scope of a flat switch meets the reality of managing these networks. Connecting old limited Layer 2 networks to Layer 3 networks is what the most advanced Web 2.0 data center companies are doing now. Fabrics are not dead, but they need to be tested in the real world of data center operational requirements and needs. In addition, SDN is becoming an interesting hot spot for fabrics. Dell does not even define it as a fabric, but calls it an end-to-end Layer 2 and 3 protocol data center network. Dell is concerned with ensuring that virtual and server compute nodes can connect to everything in the data center in a non-blocking high-bandwidth manner.

Are you moving to 40Gb and 100Gb Ethernet?

Dell believes that moving to 40Gb and 100Gb Ethernet is very important. If every server can be equipped with a 10Gb connection, and applications need to access and manage data, which means a higher density of virtual machines per server node, then the bandwidth requirements will increase exponentially. By definition, if a server has 10Gb bandwidth, then upstream traffic needs 40 or 100Gb. 100Gb is not a must. However, if you want to develop a 40Gb non-blocking distributed core architecture and want to directly scale the hub and leaf nodes, then you must have this configuration, so that you can achieve a 40Gb backbone network to achieve the maximum routing speed in the east-west direction within the rack and between the rack and the distributed core network. The combination of 10Gb and 40Gb, and more importantly, the integration in the architecture, can achieve sufficient bandwidth in the data center. Today, most of the traffic is between virtual machines; so-called east-west traffic. At this time, you must optimize the local traffic first, and then find a way to achieve a 100Gb or higher backbone network. End users outside the data center may have such a demand, but do not yet need 10Gb or 40Gb bandwidth on WAN links.

In any case, SDN and automation are very important for future networks and cloud data centers. Enterprises need to start learning to accept SDN and explore how to transition to SDN.