Using open source standards, OpenFlow makes it possible to mix and … The Software-Defined Networking (SDN) concept became the focus of the main networking research topic in academia after its resurgence in 2008[1]. This network supports massive connections, ultra … Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. The ForCES protocol can then be the CPSI and the MPSI. The infrastructure layer is just the switches and routers, and other devices that makes up a network. Network devices can be implemented in software and/or hardware. Stefano Salsano is Associate Professor at the University of Rome Tor Vergata. A typical SDN architecture consists of three layers. CAL and the MAL must be able to utilize the ForCES protocol. Examples include a virtual private LAN service, service tunnels, etc. Rather than using a command line interface, SDN-enabled networks use programmability to give flexibility and easiness to the task of implementing new applicati… SDN Controller communicate and control these upper and lower layer … MAL must be able to utilize the NETCONF protocol. The control of all the data plane devices are done via SDN Controller. Addditionally, services residing in the Application Plane may provide services to other services and applications that reside in the application plane via the service interface. This can be interpreted as having the control plane acting as a service to the management plane. However, there is increasing confusion as to what exactly SDN is, what is the layer stucture in an SDN architecture and how do layers interface with each other. The ForCES model can be used to describe the DAL, both for the Operational and the Forwarding Plane. The target reference architecture for the transport SDN controllers is hierarchical, with specific domain controllers per technological domain (IP/MPLS, microwave, optical) and a hierarchical controller to … SD-WAN architecture is a virtualized overlay on top of physical infrastructure. He is the author/co-author of a number of RFCs and drafts in the ForCES working group in IETF and the SDNRG research group in IRTF. SDN Architecture: SDN architecture layers would be consisting of 3 layers. Precise implementation details allowed within this SDN architecture are provided in more detailed ONF architecture … Figure 2-1 Solution architecture model l Physical network layer Agile network devices are used to build a basic network for deploying campus applications. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. He participated in 16 research projects funded by the EU, being Work Package leader or unit coordinator in 8 of them (ELISA, AQUILA, SIMPLICITY, Simple Mobile Services, PERIMETER, OFELIA, DREAMER/GN3plus, SCISSOR) and technical coordinator in one of them (Simple Mobile Services). When taken as a whole, the control plane has been distributed network-wide. Examples of CPSIs are ForCES [RFC5810] and the Openflow protocol [OpenFlow1.3.1]. His main field of interest is network management, network protocols and network services. A typical representation of SDN architecture includes three layers: the application layer, the control layer and the infrastructure layer. RFC7426 defines the following abstraction layers: Device and resource Abstraction Layer - abstracts the resources of the device's forwarding and operational planes to the control and management planes. First is the management plane, which is a set of network applications that manage the control logic of a software-defined network. Control Plane Services provide access to other Services or Application above the control plane. The major architectural differences between SDN and traditional network infrastructure are identified within the Control and Infrastructure layers. Its main distinguishing factor is the separation of the data plane from the control plane in routers and switches. Distribution layer Core layer Access layer If the respective planes are designed so that they do not have to reside in the same device, then the interface can only take the form of a protocol. ForCES can be mapped on the above framework as follows: Openflow can be mapped on the above framework as follows: NETCONF can be mapped on the above framework as follows: draft-haleplidis-sdnrg-layer-terminology-00, Department of Electrical and Computer Engineering, Key words for use in RFCs to Indicate Requirement Levels, Forwarding and Control Element Separation (ForCES) Protocol Specification, Forwarding and Control Element Separation (ForCES) Forwarding Element Model, YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF), Management Information Base (MIB) for the Simple Network Management Protocol (SNMP), An Architecture for Describing Simple Network Management Protocol (SNMP) Management Frameworks, The Open vSwitch Database Management Protocol, OpenFlow Management and Configuration Protocol 1.1. However, there is increasing confusion as to what exactly SDN is, what layers comprise the SDN architecture and what are the interfaces. CPSI can be implemented using a protocol, an API or even interprocess communication. This document, a product of the IRTF Software-Defined Networking Research Group (SDNRG), addresses these questions and provides a concise reference for the SDN … The SDN northbound interface is implemented in the Service Abstraction Layer. Examples of management applications include network monitoring applications. Software-defined networking (SDN) technology is an approach to network management that enables dynamic, programmatically efficient network configuration in order to improve network performance and monitoring, making it more like cloud computing than traditional network management. This interface can range from a protocol, to an API or even interprocess communication. The architecture provides a networking foundation that is easier to manage than legacy WANs. SDN architecture is structured on three primary layers, the Data plane, which consists of the network elements, the Control plane which acts as the central Controller and the Application plane which … Software-Defined Networking introduces an abstraction layer between the Forwarding and the Control layer in order to separate them. In this section, we will present a review of the architecture of SDN and OpenFlow, its main implementation, as shown in Figures 1 and 2, respectively. Control Plane & Data plane are local in SDN Model: FALSE TRUE. SDN is meant to address the fact that the static architecture … It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress.". Control plane state usually changes rapidly whilst management plane state may remain static for a longer period of time. The application layer, not surprisingly, contains the typical network … Control applications can use CAL to control a network device without providing any service to upper layers. Employing the layered architecture model introduced in RFC7426 can provide researchers and practitioners with useful guidelines on how to build disaggregated network system designs. a) an infrastructure layer b) a control layer and c) an application layer. He has been principal investigator in several research and technology transfer contracts funded by industries (Docomo, NEC, Bull Italia, OpenTechEng, Crealab, Acotel, Pointercom, s2i Italia) with a total funding of more than 1.3M€. 3. Join our free SDN Technical Community and receive IEEE Softwarization. He received his Ph.D. in Computer Science from the Department of Electrical and Computer Engineering in the University of Patras in 2016. SDN architecture. The result of this effort is the RFC7426 [4], which addresses the questions about what exactly SDN is, what the layer structure is within the SDN architecture, and how layers interface with each other. If the planes are collocated on the same device, then the interface could be implemented via an open/proprietary protocol, an open/proprietary software inter-process communication API, or operating system kernel system calls. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. The Forwarding Plane, commonly referred to as the data path, is responsible for handling and forwarding of packets. An interface may take multiple forms depending also on whether the connected planes reside on the same device or on different devices. However, there is increasing confusion as to what exactly SDN is, what layers comprise the SDN architecture and what are the interfaces. SDN, as can be seen in Figure 1, comprises several abstraction layers, interfaces and distinct planes. Timescale specifies how fast a plane responds and needs to respond. Nick McKeown, Tom Anderson, Hari Balakrishnan, Guru Parulkar, Larry Peterson, Jennifer Rexford, Scott Shenker, Jonathan Turner. Examples of service interfaces are REST APIs. Applications can use a northbound interface to talk to the controller. The list of current Internet-Drafts is at http://datatracker.ietf.org/drafts/current/. SDN Abstraction Layers. IETF Service Function Chaining Working Group, http://datatracker.ietf.org/wg/sfc. Copyright (c) 2013 IETF Trust and the persons identified as the document authors. The control plane responds in very small timescales while the management plane may not necessarily need to react fast to changes. For example, it was customary for many implementations to implement the management plane on top of the control plane. The third characteristic is locality; control plane usually is distributed and with the device, whilst management plane tends to be centralized and outside devices. However, despite the popularity of SDN in academia and industry, until recently there was a bit of confusion regarding the layers and interfaces of an SDN architecture. On the other hand, the management plane has been traditionally centralized and responsible for managing the control plane. The Control Plane may support more than one CPSIs. The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. This Internet-Draft will expire on January 16, 2014. 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