CN111130621A - Satellite network architecture based on SDN and NFV - Google Patents

Abstract

The satellite network architecture based on the SDN and the NFV provided by the invention adopts the satellite network virtualization architecture based on the SDN and the NFV, plays a role in obviously improving communication service transmission, and compared with the existing method, the combination of the SDN and the NFV technologies provides dynamic adjustment for the flow control of the application media service or performs dynamic adaptation according to problems and a problem solving way.

Description

Satellite network architecture based on SDN and NFV

Technical Field

The invention relates to a satellite network architecture based on SDN and NFV.

Background

The satellite network is entering the era of satellite-ground integrated information transmission network, and is characterized by global coverage, multiple services and reliable transmission. Satellite networks suffer from slow deployment, inefficient traffic scheduling, and inflexible service provisioning.

Combining satellite and terrestrial networks to form a single and integrated network has long been considered a promising approach to significantly improve communication services. Despite the significant and continuing advances made in satellite communication technology, the rate of development of satellite communication products is still at a gap from the rate of development of terrestrial communication systems due to the constraints on economic scale and the inherent complexities of the related art. To this end, the satellite industry is working to review and improve the role of satellite communications in the next generation of 5G networks. Therefore, there is a need to provide an efficient and flexible satellite network architecture. In recent years, new Network technologies such as Software Defined Networking (SDN) and Network Function Virtualization (NFV) provide a new method for solving the problem of the conventional satellite Network.

Satellite network virtualization based on SDN and NFV is to introduce the SDN and NFV into a satellite communication system to improve a satellite and a ground network, and enable the satellite network to further guarantee service innovation and service agility through an advanced network resource management technology, so that service quality can be improved and the requirement of fine-grained management can be met. In this way, the satellite communication system will become a service and tenant oriented system.

Disclosure of Invention

The technical problem solved by the invention is as follows: the method overcomes the defects of the prior art, provides a satellite network architecture based on SDN and NFV, adopts the satellite network virtualization architecture based on SDN and NFV, plays a role in obviously improving communication service transmission, and compared with the prior method, the combination of the SDN and NFV technologies provides dynamic adjustment for flow control of application media services or performs dynamic adaptation according to problems and a problem solving mode.

The technical scheme of the invention is as follows: a satellite network architecture based on SDN and NFV comprises a joint layer, a satellite operator module and a mobile network module;

the federation layer includes a hybrid access network and a network function virtualization coordinator; the hybrid access network is used for combining a satellite and a ground fixed or mobile access link in parallel to provide diversified services for terminal users; the network function virtualization coordinator coordinates the media service provider and the satellite operator module; the network function virtualization coordinator comprises a static virtualization mapping algorithm module and a dynamic virtualization mapping algorithm module; in the static virtualization mapping algorithm module, the information of all virtual networks is mastered before mapping, the virtual networks cannot be changed once being formed, the fixed form virtual networks are projected onto a physical network, and the corresponding resource utilization rate and the successful mapping rate are analyzed; in the dynamic virtualization mapping algorithm module, performing corresponding resource mapping according to dynamic changes of a virtual network, namely, mapping according to requirements when the virtual network is formed, completing free recovery of the mapped network, specifically, respectively mapping underlying network infrastructures, mapping virtual links to a plurality of physical links of an underlying network, and converting an unsegmentable flow problem into a polynomial solvable problem; meanwhile, the network function virtualization coordinator improves the utilization rate of physical resources by allowing multiple instances of virtual network functions to coexist in a common computing, network and storage resource pool; the network function virtualization coordinator also separates network functions from proprietary hardware so as to operate in a general commercial server, a switch and a storage unit, thereby linking the combination layer with the satellite operator module;

the satellite operator module comprises a satellite gateway and a satellite terminal; the satellite gateway and the satellite terminal are interconnected by resources of one or more channels of a communication satellite; the satellite terminal supports software defined networking technology, and in terms of network control, once the network is divided into network slices, the slices are provided to a plurality of media service providers in dedicated partitions supporting quality of service; the slices are programmable, allowing the media service provider to develop arbitrary software defined web applications to manipulate or transfer the media stream over multiple paths as needed; by adopting a software defined network technology, the satellite network presents an open interface commonly supported by a supplier, and realizes the unified management with the mobile network module;

the mobile network module comprises a ground core network, a base station, a terminal user and a service provider; the terminal user accesses the base station, and the combination of the application software defined network technology and the network function virtualization technology provides dynamic adjustment for the flow control of the application media service, or executes dynamic adaptation according to problems and problem solving ways; the software defined network is a data control separation and software programmable network architecture; the network function virtualization technology comprises a superposition networking technology, a virtualization resource scheduling technology and a virtual cluster technology; wherein, the overlay networking technology bears network application and isolates other core network services; the virtual resource scheduling technology calculates and schedules the flow in a centralized routing mode in the aspect of flow scheduling, eliminates the limitation of distributed routing, promotes the balance of the flow in the network, virtualizes the functions of a gateway, a firewall and a load balancer in the network in the aspect of service chain scheduling, forms a service chain together with the network virtualization technology, and schedules the flow to a related functional point for further processing; the virtual cluster technology comprises a homogeneous technology and a heterogeneous technology, the homogeneous virtual cluster technology is used for controlling a plane expansion process, a plurality of similar devices are converted into one virtual device, resource scheduling is flexible, information sharing is facilitated, and the heterogeneous technology integrates devices of different types with a distributed technology, so that the number of devices in network management is reduced.

The invention has the beneficial effects that:

1. while the prior art generally adopts a satellite communication system architecture, the invention adopts a satellite network virtualization architecture based on SDN and NFV, which plays a role in significantly improving communication service delivery, and compared with the prior art, the combination of SDN and NFV technologies provides dynamic adjustment for flow control of application media services, or performs dynamic adaptation according to problems and problem solving manners.

2. The prior art usually adopts a method of combining or based on SDN slices, but the invention adopts a method of combining the combination and the SDN slices, which plays a role of easily controlling resources, and is beneficial to overcoming a plurality of existing limitations in the aspects of operational flexibility, reproducibility and end-to-end service supply compared with the prior art.

3. In the prior art, satellite communication or ground base station communication is usually adopted independently, but the invention adopts the technology of integrating a satellite system and a ground base station, plays the role of expanding the communication range, and is more favorable for global coverage and reliable transmission of signals compared with the prior art.

Drawings

Fig. 1 is a schematic diagram of a satellite network virtualization architecture based on SDN and NFV.

The invention is further described below with reference to the accompanying drawings.

The invention designs a satellite network virtualization architecture based on SDN and NFV as shown in figure 1, which comprises two satellite communication scenes: the first scenario is that a terminal is connected to a satellite terminal station, the satellite terminal station sends a signal to a satellite, and then the satellite forwards the signal to a base station, and finally connection is carried out; in the second scenario, the terminal is connected to a base station, and the base station transmits a signal to a satellite through a satellite terminal station, and the satellite transmits the signal to a core network. The framework mainly adopts a method of fusing combination and SDN slice.

There is a lack of a universal standard in current satellite terrestrial network architectures (hereinafter referred to as satellite networks) and many functions are deployed primarily on network equipment of a particular vendor performing a particular function, which makes network infrastructure setup very prone to vendor lock-out, difficult to manage when solutions from different vendors are operated together. Major innovations are realized by introducing SDN and NFV technologies, and it is expected that satellite network operators will gain greater flexibility, enabling reductions in the operation and capital expenditure of network equipment while deploying and managing SDN and NFV within a satellite network. Thus, the application of SDN and NFV to satellite networks is a key driving factor for achieving flexible integration of satellite and terrestrial networks, which is beneficial to overcome several existing limitations in operational flexibility, scalability, and end-to-end service provisioning.

The satellite network virtualization architecture based on the SDN and the NFV mainly comprises three parts, namely a joint layer, a satellite operator and a mobile network operator. SDN and NFV technologies and SDN-based network slicing technologies are introduced into the architecture.

Satellite network virtualization architecture based on SDN and NFV

1. Combined layer

A hybrid access network is a network that combines a satellite portion and a terrestrial portion in parallel. A properly combined satellite and terrestrial link may enable a Service that provides better Quality of Service (QoS) or Quality of Experience (QoE) and diversity to the end user. An important approach to the combination of satellite and terrestrial access networks is federation. Federation refers to pooling network resources from two or more domains and using it as one logical domain to control the resources more easily. The NFV coordinator coordinates the media service provider and the satellite operator. The use of NFV allows dynamic deployment and instantiation of Virtual Network Functions (VNFs) at the media service provider side or at the client, which helps to provide requested media services while maintaining appropriate QoE.

2. Satellite operator

Satellite Operators (SOs) are responsible for maintaining, managing, deploying, and operating the Satellite platforms. The Satellite operator includes a Satellite Gateway (GW) and a Satellite Terminal (ST), a Network Control Center (NCC) and a Network Management Center (NMC), and their respective functions are as follows:

1) the GW and ST are interconnected by one or more channels of a communications satellite. It may use various network topologies (star, multi-star, mesh hybrid star), one GW may provide access to different logically separate ST groups.

2) The NCC provides real-time control of the satellite network (e.g., connection control, including signaling required to establish, supervise, and release connections), and the NMC is responsible for managing system elements of the satellite network (e.g., configuration, fault, performance, and security management).

3. Mobile network module

The mobile network module consists of a ground core network, a base station, a terminal user and a service provider.

1) A ground core network: the system comprises a core network access and mobility management function, a session management function, a user layer function, an authorization service function, a strategy control function, a unified data service, an application function and a data network function.

2) A base station: for access by the end user.

3) The end user: the system comprises mobile equipment such as a mobile phone and a computer and mixed customer premises equipment supporting SDN and NFV.

4) Service Provider (SP): the SP sells services and or devices to customers (end users or other service providers) responsible for managing and operating the relevant service provider elements in the ST and GW.

Techniques introduced in architecture

SDN and NFV techniques

In the terrestrial domain in the architecture shown in fig. 1, there are limitations such as lack of automation and limited service flexibility, but these problems can be solved by SDN and NFV technologies. In one aspect, SDN separates the control and user planes of network devices and logically centralizes the network intelligence (i.e., the control plane), while the underlying network infrastructure (i.e., the user plane) is abstracted to external applications that request services through the control plane. In this sense, SDN constitutes a new architectural paradigm for designing network functions (e.g., routing, load balancing, firewalls) that can provide abstraction, facilitate programming, and simplify management functions through standard interfaces. NFV, on the other hand, has the scope to separate network functions from proprietary hardware so that these functions can be run in general purpose commercial servers, switches and storage units. By implementing network functions in software running on a series of industry standard servers, the operator does not have to install new proprietary equipment within the network. Furthermore, NFV increases the utilization of physical resources by allowing multiple instances of VNFs to coexist in a common pool of computing, network, and storage resources. .

Reconfigurability, developability, and programmability are three key features that facilitate joint implementation, while SDN and NFV are the most promising technologies. By adopting the SDN technology, the satellite network can present an open interface universally supported by a supplier, and the unified management with the ground network is realized. Similarly, the NFV technology simplifies the provision of value-added network services in satellite communication systems by extending the terrestrial NFV management framework to meet the requirements of satellite communication systems. In the present invention, the satellite end stations each support SDN technology, and in terms of network control, once the network is divided into network slices, these slices can be provided to multiple media service providers in dedicated zones that support QoS. In addition, the slices are programmable, allowing media service providers to develop arbitrary SDN applications to manipulate or transfer media streams over multiple paths as needed. This is an important function compared to current static non-programmable federation. Thus, the combination of SDN and NFV technologies provides dynamic adjustment for flow control of application media services, or performs dynamic adaptation according to the problem and the way the problem is solved.

2. SDN-based network slicing

The present architecture provides a specific form of tunneling for satellite networks using SDN-based network slices, which can provide advanced capacity handling and QoS support if needed to support a specific (type) mobile network operator network slice. The architecture depicted in fig. 1 demonstrates the situation where a Satellite Network Operator (SNO) Network provides transport connectivity to multiple Mobile Network Operators (MNOs) and various (types of) slices used by the MNOs, which are controlled by the MNOs for setup and maintenance of SDN-based Network slices in the SNO Network.

One important reason for using SDN-based network slices is that each MNO network can use the same IP address on its transport network for backhaul, i.e., on the SNO network. Therefore, it is desirable to isolate the MNO networks (through some form of tunneling) in the SNO network in the IP address. Furthermore, each MNO network may require specific support for their own slices from the SNO network, which may be provided by SDN-based network slices using separate SNOs for certain MNO slice(s).

The SDN-based network slicing is realized by combining an extended slicing technology with the SDN, and the key point is to control slicing extension from the UE of the core network by the SDN technology.

SDN-based slice extension is based on the following assumptions: at the satellite terminal side (virtual or physical) there is an SDN switch, which is controlled by an SDN controller in the SNO ground station. In this way, the flexibility provided by the SDN may be used to create a suitable implementation of a desired SDN-based network slice.

An implementation of the architecture depicted in fig. 1 may employ the ETSI NFV architecture, where each component is supported by a Network Function Virtualization Infrastructure (NFVI). However, in order to simplify the architecture, only the SDN architecture needs to be adopted. Figure 1 demonstrates the advantages created by the union of SDN and NFV for satellite and terrestrial domains to optimize content distribution. The opportunity created for mixed distribution of digital media through a federated system supporting SDN and NFV goes beyond the typical combination of satellite broadcast television with IP content (such as hybrid broadcast broadband television or second screen applications). As part of the overall 5G system, this scenario will focus more on the issues faced by satellite networks in interfacing with other terrestrial networks in a dynamic and flexible manner, and how SDN and NFV technologies help mitigate these effects on satellite communications to maintain QoS for the services provided.

The present invention has not been described in detail as is known to those skilled in the art.

Claims (1)

1. A satellite network architecture based on SDN and NFV, characterized by: the system comprises a combination layer, a satellite operator module and a mobile network module;

the federation layer includes a hybrid access network and a network function virtualization coordinator; the hybrid access network is used for combining a satellite and a ground fixed or mobile access link in parallel to provide diversified services for terminal users; the network function virtualization coordinator coordinates the media service provider and the satellite operator module; the network function virtualization coordinator comprises a static virtualization mapping algorithm module and a dynamic virtualization mapping algorithm module; in the static virtualization mapping algorithm module, the information of all virtual networks is mastered before mapping, the virtual networks cannot be changed once being formed, the fixed form virtual networks are projected onto a physical network, and the corresponding resource utilization rate and the successful mapping rate are analyzed; in the dynamic virtualization mapping algorithm module, performing corresponding resource mapping according to dynamic changes of a virtual network, namely, mapping according to requirements when the virtual network is formed, completing free recovery of the mapped network, specifically, respectively mapping underlying network infrastructures, mapping virtual links to a plurality of physical links of an underlying network, and converting an unsegmentable flow problem into a polynomial solvable problem; meanwhile, the network function virtualization coordinator improves the utilization rate of physical resources by allowing multiple instances of virtual network functions to coexist in a common computing, network and storage resource pool; the network function virtualization coordinator also separates network functions from proprietary hardware so as to operate in a general commercial server, a switch and a storage unit, thereby linking the combination layer with the satellite operator module;

the satellite operator module comprises a satellite gateway and a satellite terminal; the satellite gateway and the satellite terminal are interconnected by resources of one or more channels of a communication satellite; the satellite terminal supports software defined networking technology, and in terms of network control, once the network is divided into network slices, the slices are provided to a plurality of media service providers in dedicated partitions supporting quality of service; the slices are programmable, allowing the media service provider to develop arbitrary software defined web applications to manipulate or transfer the media stream over multiple paths as needed; by adopting a software defined network technology, the satellite network presents an open interface commonly supported by a supplier, and realizes the unified management with the mobile network module;

the mobile network module comprises a ground core network, a base station, a terminal user and a service provider; the terminal user accesses the base station, and the combination of the application software defined network technology and the network function virtualization technology provides dynamic adjustment for the flow control of the application media service, or executes dynamic adaptation according to problems and problem solving ways; the software defined network is a data control separation and software programmable network architecture; the network function virtualization technology comprises a superposition networking technology, a virtualization resource scheduling technology and a virtual cluster technology; wherein, the overlay networking technology bears network application and isolates other core network services; the virtual resource scheduling technology calculates and schedules the flow in a centralized routing mode in the aspect of flow scheduling, eliminates the limitation of distributed routing, promotes the balance of the flow in the network, virtualizes the functions of a gateway, a firewall and a load balancer in the network in the aspect of service chain scheduling, forms a service chain together with the network virtualization technology, and schedules the flow to a related functional point for further processing; the virtual cluster technology comprises a homogeneous technology and a heterogeneous technology, the homogeneous virtual cluster technology is used for controlling a plane expansion process, a plurality of similar devices are converted into one virtual device, resource scheduling is flexible, information sharing is facilitated, and the heterogeneous technology integrates devices of different types with a distributed technology, so that the number of devices in network management is reduced.

Images