Software Defined Networking: A New Networking Approach

Transcription

1 Software Defined Networking: A New Networking Approach Gunjan Katwal #, Ayushi Nainwal * # Computer Science, AP Goyal University Shimla 1 gun363@gmail.com 2 AyushiNainwal@gmail.com ABSTRACT Software defined networking (SDN) is a new type of networking approach. In earlier networks, there were seven layers but the SDN support only three layers. The three tiered architecture of SDN promises to simplify the network management. Network operators, and services and product providers require a new network solution to efficiently tackle the increasing demands of this changing network landscape. Software defined networking has emerged as an efficient network technology capable of supporting the dynamic nature of future network functions and intelligent applications while lowering operating costs through simplified hardware, software, and management. SDN allows users to control the components of the networking environment via software rather than the traditional approach via hardware. In this paper, we will study the new networking approach which will overcome some of the shortcomings faced in the traditional networks. Keywords SDN, Open Flow, SDN Controller, Data Plane, Interface. INTRODUCTION This The Software Defined Networking (SDN) is a new networking approach. The traditional networking architectures are not capable of fulfilling the changing needs and requirements of networking organizations and individual users. In traditional network it is very difficult to manage the network because network consists of heterogeneous hardware devices that support different protocols. SDN paradigm helps us to solve these problems by enabling the separation of the control plane from data plane [1]. The physical separation of control- and forwarding- or data plane is the best known principle of SDN. It postulates the externalization of the control plane from a network device to an external control plane entity often called the controller. In particular, this means that an internal 92

2 software control plane, while it may still exist, is not enough to brand a device or technology as Software Defined Networking [2]. There are several new emerging approaches to networking under the field of SDN, which bring, separation of data and control planes. As elastic cloud architectures and dynamic resource allocation evolve and as mobile computer operating systems and virtual machines usage grows, the need has arisen for an additional layer of Software Defined Networking (SDN). Such a layer allows network operators to specify network services, without coupling these specifications with network interfaces. This enables entities to move between interfaces without changing identities or violating specifications. Such a layer allows network operators to specify network services, without coupling these specifications with network interfaces. This enables entities to move between interfaces without changing identities or violating specifications. Such a layer can also reset some of the complexity build-up in network elements by decoupling identity and flowspecific control logic from basic topology based forwarding, bridging, and routing [3]. EVOLUTION A broader interpretation of Software Defined Networks can include appliances in the cloud and smart mobile devices. Further, the same interpretive framework can incorporate storage and traditional end system computation, which would allow coherent optimization across all resources and components of a distributed service, using consistent techniques familiar to software engineers the world over, instead of stove-piped methods for each sector. In the next section, we explain why protocols are both a hindrance and a help, and introduce soft or flexible protocols as our concept for crossing the divide into full network programmability [4]. SDN ARCHITECTURE The main idea behind SDN is to separate the forwarding/data plane from the control plane while providing programmability on the control plane is shown in Figure 1.1: 1) Control Plane The control plane/controller presents an abstract view of the complete network infrastructure, enabling the administrator to apply custom policies/protocols across the network hardware. The network operating system (NOX) controller is the most widely deployed controller. 93

3 2) Northbound Application Interfaces Fig 1 SDN Architecture The northbound" application programming interfaces (APIs) represent the software interfaces between the software modules of the controller platform and the SDN applications running atop the network platform. These APIs expose universal network abstraction data models and functionality for use by network applications. The northbound APIs are open source-based. 3) East-West Protocols In the case of a multi-controller-based architecture, the East- West interface protocol manages interactions between the various controllers. 4) Data Plane and Southbound Protocols The data plane represents the forwarding hardware in the SDN network architecture. Because the controller needs to communicate with the network infrastructure, it requires certain protocols to 94

4 control and manage the interface between various pieces of network equipment. The most popular southbound protocol is the Open Flow protocol. The following section explains Open Flow and its architecture [5]. SDN BENEFITS SDN provides several benefits to address the challenges facing legacy network architectures. 1) Programmability of the Network: By implementing a new orchestration level, SDN can tackle the inflexibility and complexity of the traditional network. SDN provides enterprises with the ability to control their networks programmatically and to scale them without affecting performance, reliability, or the user experience. The data and control-plane abstractions constitute the immense worth of SDN. By eliminating the complexity of the infrastructure layer and adding visibility for applications and services. 2) The Rise of Virtualization SDN is a promising opportunity for managing hyper-scale data centers (DCs). Data centers raise significant scalability issues, especially with the growth of virtual machines (VMs) and their migration. Moving a VM and updating the media access control (MAC) address table using traditional network architecture may interrupt the user experience and applications. Therefore, network virtualization, which can be seen as an SDN application, offers a prominent opportunity for hyperscale data centers. It provides tunnels that can abstract the MAC address from the infrastructure layer, enabling Layer 2 traffic to run over Layer 3 overlays and simplifying VM 3) Device Configuration and Troubleshooting: With SDN, device configuration and troubleshooting can be done from a single point on the network which pushes us closer to realizing the ultimate goal of a dynamic network that can be configured and made adaptable according to needs. SDN also provides the capability to encourage innovation in the networking field by offering a programmable platform for experiments on novel protocols and policies using production traffic. Separating data flows from test flows facilitates the adoption of newer protocols and ideas into the networking domain [6, 7]. 95

5 CONCLUSION The traditional networking architecture can t accommodate the advance user requirements efficiently. Increase of mobile devices, virtualization, high automation & security, efficient Big- Data management and high quality with variety of services, SDN is a promising architecture [8]. For sure current network is not dynamic if compared to SDN. Though yet SDN, needs some time to mature and industry also need time to synchronize the devices according to it. SDN can also manage optical and wireless networks fruitfully. To understand why SDN will play a critical role in future in shaping various technologies, we have to think what actually SDN providing us apart from all technical advances. SDN gives user or operator a feel of nearness to the network. He won t feel that he is a distinct entity when operating on SDN based networks. Hence it is true to say that future networks will revolve around SDN based networking. REFERENCES [1] Nick Feamster, Jennifer Rexford, Ellen Zegura, The Road to SDN: An Intellectual History of Programmable Networks. ACM SIGCOMM, Volume 44 Issue 2, 2014, [2] M. Casado, D. Erickson, I. A. Ganichev, R. Griffith, B. Heller, N. McKeown, D. Moon, T. Koponen, S. Shenker, and K. Zarifis, Ripcord: A Modular Platform for Data Center Networking, Tech. Rep. UCB/EECS , EECS Department, University of California, Berkeley, June [3] Software _ Defined _ Networking. [4] J. Su, J. Scott, P. Hui, J. Crowcroft, E. De Lara, C. Diot, A. Goel, M. H. Lim, and E. Upton, Haggle: seamless networking for mobile applications, In Proceedings of the 9th international conference on Ubiquitous computing, UbiComp 07, pp , Berlin, Heidelberg, Springer-Verlag. [5] Brocade Communications Systems, Network Transformation with Software-Defined Networking and Ethernet Fabrics, California, USA, network-transformation-sdn-wp.pdf, [6] HP, "Deliver HP Virtual Application Networks," [7] HP, "Realizing the Power of SDN with HP Virtual Application Networks," [8] Vijay K. Gurbani, M Scharf, T.V. Lakshman and V. Hilt. Bell Laboratories, Alcatel- Lucent"Abstracting network state in Software Defined Networks (SDN) for rendezvous services"." Communications (ICC), 2012 IEEE International Conference on Software Defined Networks. (2012). 96