Jun. 8, 2012

NTT DATA Corporation

Recently years, since the requirements for information system are becoming more complex and diversified, there is strong demand for the systems which can respond the changing market quickly. However, in the traditional network, cumbersome operation is necessary when changing the network configuration and it was difficult to follow the changes of system configuration flexibly. Therefore, in the field of network, as a technology that can control network freely by software, SDN has got a great deal of expectation. ONF (Open Networking Foundation) was established as the champion of SDN and steward of the OpenFlow Standard, which is a critical component and provides the fundamental foundation for SDN.

Traditionally both the control plane and the forwarding plane are mounted in the same network device. In OpenFlow the controller is separated from the forwarding plane. As this enables the control of network devices in a whole and allows easy cooperation with other systems, the operation costs of network can be reduced by more than 50% compared with the traditional network. Many other applications are also expected ^{(see note 2)}. As a result, OpenFlow has attracted plenty of attention from not only large-scale network operators and cloud operators, but also various other IT companies ^{(see note 3)}.

NTT DATA has been conducting the research and development on OpenFlow from 2010. NTT group, including NTT DATA, has been a board member ^{(see note 4)} of ONF from 2011 and contributed much to the standardization of OpenFlow.

In 2011, with the cooperation of 5 companies of leading network equipment vendors and virtualization software vendors, NTT DATA carried out successfully the verification experiment ^{(see note 5)} of OpenFlow technology in a multi-vendor environment. Utilizing the results of the verification, NTT DATA has advanced the commercialization of OpenFlow and completed the development of Hinemos Virtual Network Management Option (on sale from June 5) ^{(see note 6)} and Virtual Network Controller Ver1.0 ^{(see note 7)} that was adopted in Cloud System for Researchers by National Institute of Informatics, Research Organization of Information and Systems, Inter-University Research Institute Corporation.

In addition, NTT DATA has developed a function which can select the communication path by traffic and improve the utilization efficiency of networks ^{(see note 8)}. The OpenFlow controller that implemented this function has been used actually in the in-house data center of NTT DATA.

Based on the know-how accumulated through the efforts described above and aimed at further optimization of information system, NTT DATA has started the development of a new OpenFlow controller Virtual Network Controller Ver2.0 which can supports WAN and enterprise network as well as the data center network. NTT DATA plans to start selling of Virtual Network Controller Ver2.0 later this year. Together with the sale of this controller, NTT DATA will start its SDN business such as network integration using OpenFlow, system development and consulting services of OpenFlow introduction.

The prototype of Virtual Network Controller Ver2.0 is compliant with OpenFlow Ver1.0 and has the following 4 features.

As approaches to the implementation of OpenFlow network this controller supports, the first time in the world, both hop-by-hop method and overlay method. The combined use of the both is also supported. Using hop-to-hop method, since the controller has the function of assigning preferentially the path with low traffic to new packets, the utilization efficiency of network can be improved from conventional 40% or less to nearly 100% (Figure 1). In addition, since the overlay method can make use of the existing network equipment when adopting OpenFlow technology, the introduction of OpenFlow with reduced initial investment cost is possible.

To be more specific, using this controller the customer can introduce OpenFlow at first in overlay method to make use of its existing network equipment. Secondly, the transition to hop-by-hop method can be carried out by replacing the existing equipment gradually with OpenFlow-enabled equipment, and thus the network utilization efficiency will be improved further. In this way, tailored to customer’s network environment, the network virtualization and efficient utilization can be realized in a phased manner (Figure 2).

Virtual Network Controller Ver2.0 has a high connectivity with existing network devices and a small start, i.e., introduction of network virtualization only in part of system, is possible. Since the connection (Figure 3, left) by redundant L3 switches and the connection (Figure 3, right) by multi-chassis link aggregation ^{(see note 9)} are supported, you can easily increase the bandwidth between existing switches and OpenFlow switches, and improve the reliability. In addition, this controller also has a high affinity with the existing network virtualization technology and, based on the combination of VLAN multiplexed ^{(see note 10)} network and the network built by OpenFlow, facilitates the implementation of multi-tenant system ^{(see note 11)}. Usually the communication between different closed networks is forwarded via L3 switch. But since this controller allows direct connection between the servers of different closed networks, the L3 switch is not needed (Figure 4).

Virtual Network Controller Ver2.0 provides a set of general-purpose API which can change the network configuration freely. Using the APIs, advanced cooperation with management software such as Hinemos and cloud infrastructure such as OpenStack is possible. Group of switches can be controlled as a whole via API. Compared with the conventional network, more than 50% reduction of operation costs can be expected. In addition, since API is an abstraction of network function, the operation and management of network is easy even for the users who do not have the advanced expertise. Switches can be added without special configuration changes and service interruption. Vendor lock-in is not necessary and a number of switches verified by NTT DATA can be used freely.

Live migration (between physical servers) among data centers is supported by utilizing the tunneling technique ^{(see note 12)} of overlay method. In the case of live migration among various data centers, MAC addresses assigned by cloud infrastructure are not guaranteed to be unique and the duplicative MAC addresses may have adverse impact on communication. NTT DATA suggested an original approach for this problem and duplicative MAC addresses of VM are allowed (Figure 5).

NTT DATA will display and demonstrate a prototype of Virtual Network Controller Ver2.0 at Interop Tokyo 2012 exhibition held from June 13 to 15. A presentation about Virtual Network Controller is also scheduled at the exhibition. In addition, the controller will be used also to improve the function of Hinemos Virtual Network Management Option.

In time with the sale of the controller, we are planning to offer our internal developing API as open source. These APIs can be used for the development of user’s original functions. A plan for recruiting development partner is also scheduled.

NTT DATA is aimed at a billion-yen-a-year sale related to Virtual Network Controller.