The 2018 Open Networking Summit is rapidly approaching. In anticipation of this event, we spoke to Shunmin Zhu, Head of Alibaba Cloud Network Services to get more insights on two of the hot topics that will be discussed at the event: the future of Software Defined Networking (SDN) and the emerging SD-WAN technology.
“SDN is a network design approach beyond just a technology protocol. The core idea is decoupling the forwarding plane from the control plane and management plane. In this way, network switches and routers only focus on packet forwarding,” said Zhu.
“The forwarding policies and rules are centrally managed by a controller. From a cloud service provider’s perspective, SDN enables customers to manage their private networks in a more intelligent manner through API.”
This newfound approach to networks that were previously thought to be nearly unfathomable black boxes brings welcome transparency and flexibility. And, that naturally leads to more innovation such as SD-WAN and Hybrid-WAN.
Zhu shared more information on both of those cutting-edge developments later in this interview. Here is what he had to say about how all these things come together to shape the future of the networking.
Linux.com: Please tell us a little more about SDN for the benefit of readers who may not be familiar with it.
Shunmin Zhu: Today, cloud services make it very convenient for a user to buy a virtual machine, set up the VM, change the configurations at any time, and choose the most suitable billing method. SDN offers the flexibility of using network products the same way as using a VM. Such degree of flexibility was not seen in networks before the advent of SDN.
Before, it was unlikely for a user to divide his cloud network into several private subnets. In the SDN era, however, with VPC (Virtual Private Cloud) users are able to customize their cloud networks by choosing the private subnets and dividing them further. In short, SDN puts the power of cloud network self-management into the hands of users.
Linux.com: What were the drivers behind the development of SDN? What are the drivers spurring its adoption now?
Zhu: Traditional networks prior to SDN find it hard to support the rapid development of business applications. The past few decades witnessed fast growth in the computing industry but not so much innovation was seen in the networking sector. With emerging trends, such as cloud computing and virtualization, organizations need their networks to become as flexible as the cloud computing and storage resources in order to respond to IT and business requirements. Meanwhile the hardware, operating system, and network application of the traditional network are tightly coupled and not accessible to an outsider. The three components are usually controlled by the same OEM. Any innovation or update is thus heavily dependent on the device OEMs.
The shortcomings of the traditional network are apparent from a user’s perspective. First and foremost is the speed of delivery. Network capacity extension usually takes several months, and even a simple network configuration could take several days, which is hard for customers to accept today.
From the perspective of an Internet Service Provider (ISP), the traditional network could hardly satisfy the need of their customers. Additionally, heterogeneous network devices from multiple vendors complicate network management. There’s little that ISPs could do to improve the situation as the network functions are controlled by the device OEMs. User and carrier’s urgent need for SDN has made this technology popular. In a large extent, SDN overcomes the heterogeneity of the physical network devices and opens up network functions via APIs. Business applications can call APIs to turn on network services on demand, which is revolutionary in the network industry.
Linux.com: What are the business benefits overall?
Zhu: The benefits of SDN are twofold. On the one hand, it helps to reduce cost, increase productivity, and reuse the network resources. SDN makes the use of networking products and services very easy and flexible. It gives users the option to pay by usage or by duration. The cost reduction and productivity boost empowers the users to invest more time and money into core business and application innovations. SDN also increases the reuse of the overall network resources in an organization.
On the other hand, SDN brings new innovations and business opportunities to the networking industry. SDN technology is fundamentally reshaping networking toward a more open and prosperous ecosystem. Traditionally, only a few network device manufacturers and ISPs were the major players in the networking industry. With the arrival of SDN, more participants are encouraged to create new networking applications and services, generating tons of new business opportunities.
Linux.com: Why is SDN gaining in popularity now?
Zhu: SDN is gaining momentum because it brings revolutionary changes and tremendous business value to the networking industry. The rise of cloud computing is another factor that accelerates the adoption of SDN. The cloud computing network offers the perfect usage scenario for SDN to quickly land as a real-world application. The vast scale, large scope, and various needs of the cloud network pose a big challenge to the traditional network. SDN technology works very well with cloud computing in terms of elasticity. SDN virtualizes the underlay physical network to provide richer and more customized services to the vast number of cloud computing users.
Linux.com: What are future trends in SDN and the emerging SD-WAN technology?
Zhu: First of all, I think SDN will be adopted in more networking usage scenarios. Most of the future networks will be designed by the rule of SDN. In addition to cloud computing data centers, WAN, carrier networks, campus networks, and even wireless networks will increasingly embrace the adoption of SDN.
Secondly, network infrastructure based on SDN will further combine the power of hardware and software. By definition, SDN is software defined network. The technology seems to be prone to the software side. On the flipside, SDN cannot leave the physical network devices upon which it builds the virtual network. The difficulty to improve performance is another disadvantage of a pure software-based solution. In my vision, SDN technology will evolve towards a tighter combination with hardware.
The more powerful next generation network will be built upon the mutually reinforcing software and hardware. Some cloud service providers have already started to use SmartNIC as a core component in their SDN solution for performance boost.
The next trend is the rapid development of SDN-based network applications. SDN helps build an open industry environment. It’s a good time for technology companies to start businesses around innovative network applications such as network monitoring, network analytics, cyber security and NFV (Network Function Virtualization).
SD-WAN is the application of SDN technology in the wide area network (WAN) space. Generally speaking, WAN refers to a communications network that connects multiple remote local area networks (LANs) with a distance of tens to thousands of miles to each other. For example, a corporate WAN may connect the networks of its headquarters, branch offices, and cloud service providers. Traditional WAN solutions, such as MPLS, could be expensive and require a long period before service provisioning. Wireless networks, on the other hand, fall short in bandwidth capacity and stability. The invention of SD-WAN fixes these problems to a large extent.
For instance, a company can build its corporate WAN by connecting branch offices to the headquarters via virtual dedicated line and internet, also known as a Hybrid-WAN solution. The Internet link brings convenience to network connections between the branches to the headquarters while the virtual dedicated line guarantees the quality of the network service. The Hybrid-WAN solution balances cost, efficiency, and quality in creating a corporate WAN. Other benefits of SD-WAN include SLA, QoS, and application-aware routing rules – key applications are tagged and prioritized in network communication for a better performance. With these benefits, SD-WAN is getting increasing attention and popularity.
Linux.com: What kind of user experience do you think is expected regarding SDN products and services?
Zhu: There are three things that are most important to SDN user experience. First is the simplicity. Networking technologies and products sometimes impress users as over complicated and hard to manage. The SDN network products should be radically simplified. Even a user with limited knowledge in networking should be able to use and configure the product.
Second is the intelligence. SDN network products should be smart enough to identify incidents and fix the issues by itself. This will minimize the impact to the customer’s business and reduce the management costs.
The third most important thing is the transparency. The network is the underlying infrastructure to all applications. The lack of transparency sometimes makes users feel that their network is a black box. A successful SDN product should give more transparency to the network administrators and other network users.
This article was sponsored by Alibaba and written by Linux.com.
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