Research On Key Virtualization Technologies In Forces-Based SDN Configuration Layer

With the appearance of some new type of application, new demand’s dependence on the Internet is no longer a high-powered data forwarding performance, but an open, flexible network to adapt to a variety of different types of business requests. Under this background, the concept of Software Defined Network (SDN) was put forward, and it means to accomplish the dynamic management of network resources by software definition. Thus users can dynamically build data forwarding network with various features by programming, which can meet the demand of various applications.It is paid much attention in the industry when SDN is proposed, and it is regarded as the future development direction of network research. At present the implementation of SDN architecture is still a controversial subject. Many of the techniques represented by OpenFlow are tried to realize the SDN, and ForCES is the up-rising star. The ForCES refers to separation of Forwarding Element (CE) and Control Element (FE), and it implements the centralized control by CE to FE. Fittingly, the idea of separation and centralized control is also advocated by SDN architecture. In addition, ForCES well abstracts and defines its open resources, which provides a good support to network virtualization for SDN. Therefore, research on ForCES-based SDN has become a hot spot.Under the guidance that to use ForCES to implement the SDN architecture, this paper proposes an innovative overall SDN framework based on ForCES. At the same time, under the direction of SDN network virtualization, the paper researches and implements two key techniques in it.The first part is the RESTful API of SDN based on ForCES, which provides a channel for issue of network virtualization request. Specific content as follows:first, according to the analysis of interface requirements and form, choose REST API as the northbound interface of SDN; Second, put forward the REST-based northbound interface framework and normalize the northbound interface, that is taking four common HTTP operations for a limited operation group to access the network resources identified by URL; Third, build a data model for network resources to be loaded into the REST server; Forth, accomplish the whole northbound interface construction by utilizing the Restlet which is a software implementation framework of SDN. The second part is constructing a virtual network node basing on LFB assembly. LFB is the core and characteristic of ForCES. As discretized abstract of FE resources in ForCES, LFB itself is a kind of virtualization. Thus LFB assembly can be regarded as a way of implementation of node virtualization in ForCES-based SDN. LFB assembly bases on input and output matching algorithm, in which LFB model, its formal description and concept of a series of relations between LFBs are defined. Accordingly, two kinds of assembly algorithms are proposed, which are single-track assembly and concurrent opposite direction assembly algorithm.At last, the northbound interface of ForCES-based SDN and the assembly algorithms are stimulated and tested. At the same time efficiency of the two algorithms are compared.