During the last years, the telecom/network community is pursuing a paradigm shift towards the virtualisation/ “softwarisation” of infrastructure components, enabling a novel “cloud networking” model, which allows the flexible management of network resources and functionalities in a cloud-like manner. Future networks are envisaged to consist of heterogeneous wireless and wired physical infrastructures, whose resources are abstracted via virtualisation mechanisms, unified, dynamically pooled and offered as-a-Service to multiple tenants.
In order to be able to benefit from such a progress and also seamlessly integrate with future networks in the 5G context, it would be advisable that satellite communication platforms follow this transformation, currently occurring in the terrestrial segment. The CloudSat study focuses on this issue, studying the applicability of virtualisation and softwarisation technologies to satcom platforms and determining the benefits and the challenges associated with the integration of satellite infrastructures into future cloud networks.
To this end, the CloudSat study:
- Reviews state-of-the-art virtualisation and softwarisation technologies, focusing on Software Defined Networking (SDN) and Network Functions Virtualisation (NFV)
- Determines the applicability of these technologies to satcom
- Identifies specific use cases/integration scenarios and studies their techno-economic efficiency
- Defines integrated virtualised satellite/terrestrial architectures and validates them in a lab environment
- Produces a roadmap and recommendations for future virtualisation-capable satellite networks.
Satellite/terrestrial federated services via virtualisation (SDN/NFV)
The project addresses key issues associated with the inclusion of satellite components into future federated virtualised networks in the 5G context, such as:
- the perspectives and challenges of federated satellite/terrestrial network management
- the extent to which satellite resources can be virtualised and up/down scaled in an elastic, cloud-like manner
- the benefits as well as the issues associated with the application of SDN and Openflow in the ground segment and also on-board
- the benefits as well as the issues associated with the virtualisation of several satcom network functions according to the NFV paradigm
- the impact of virtualisation technologies on the satellite industry, the satcom market and the value chain configuration.
SYSTEM ARCHITECTURE
CloudSat designs and implements (in lab environment) a federated satellite-terrestrial network platform supporting virtualization and programmability.
The CloudSat proof-of-concept implementation features three essential segments: the emulated satellite network segment, the terrestrial network segment and the management and orchestration segment.
CloudSat proof-of-concept architecture
- The emulated satellite network segment is based on the OpenSAND satellite network emulator. The OpenSAND gateway is integrated with an Openflow-enabled virtual (software) switch such as the OpenVSwitch (OVS) in order to enable Openflow-based control of the satellite infrastructure. Also, an OpenStack compute cluster is deployed at the Gateway side, in order to enrich the satellite segment with NFV capabilities.
- The emulated terrestrial network segment consists of physical Openflow-enabled switches, aimed to emulate an Openflow-capable terrestrial core/edge network infrastructure, with a wireless access part i.e. based on WiFi.
- The management/orchestration segment consists of the modules that achieve the federated management of resources across the terrestrial and satellite domains. A Network/SDN Controller is required for the management of the hybrid network topology and the provisioning of virtual networks; OpenDaylight is the most candidate platform for this task. A Cloud/NFV Controller is also required for the management of IT resources allocated to the hosting of virtual network functions (VNFs); Openstack is the most likely solution to be used.
The satcom community is expected to derive significant benefits from the adoption of the SDN/NFV model and the interoperability/integration with terrestrial software-based networks. Some high-level benefits can be identified per category of stakeholders as follows:
- Benefits for satcom equipment manufacturers: by adopting the SDN/NFV paradigm, equipment vendors developing specialised networking equipment for specific use (onboard or ground), have the potential to “open” their platform by making it programmable and reconfigurable, compliant with standard northbound interfaces for management; this is a unique opportunity to drastically widen their target customer groups and thus strengthen their position in the global market.
- Benefits for satellite network operators: the software-based network paradigm is expected to be a very attractive revenue source for satcom operators, who are able to monetize on their network by offering new satellite-based services and by charging customers according to the actual usage of in-network resources, as opposed to claiming flat fees for plain connectivity services providing applications “over-the-top” with no QoS guarantees and no in-network functionalities. Another key benefit for satellite network operators is the cost reduction, achieved via NFV, i.e., via the employment of commodity server nodes for network functionalities (e.g. proxying, PEP, caching, transcoding etc.), instead of expensive specialised networking equipment; this also allows easy upgrade and replacement, but also deployment of new innovative functions with minimal delay and cost.
- Benefits for satellite network customers: Satellite network customers – especially enterprise ones – gain access to a fully virtualized flexible infrastructure with elevated management and configuration capabilities. They are able to interconnect remote locations via isolated virtual slices with flexible SLAs and QoS, using both terrestrial and satellite connectivity, and be charged according to usage, while the service resources can be at any time re-scaled according to their needs. Furthermore, the capabilities of NFV allow them to migrate hardware networking appliances (network gateways, firewalls, transcoders, etc.) to the operators’ cloud infrastructure, thus shifting CAPEX to OPEX and enjoying all the advantages of the cloud paradigm.
The project started September 2014 and has a duration of 15 months. The technical project work is broken down into four workpackages:
- WP1 (Cloud Networking Techniques and Technologies for Terrestrial Wired and Wireless Networks) performs an extensive state-of-the-art survey of emerging virtualisation technologies (Duration: M1-M3).
- WP2 (Dimensions of Suitability with Satellite Networks and Integration Scenarios) assesses the suitability of the surveyed technologies to satcom and identifies candidate use cases (Duration: M3-M6)
- WP3 (Integrated Cloud Networking Architectures Definition and Validation) designs, validates and assesses the techno-economic efficiency of federated virtualised architectures (Duration: M5-M13)
- WP4 (Future Work Recommendations, Technology Development Roadmap and Standards Evolution) produces recommendations for technology evolution (Duration: M9–M15)
Three project milestone reviews are planned:
- CNTTR in M6 reviews the outcomes of WP1 and WP2
- IAR in M13 reviews the outcome of WP3
FR at the end of the project reviews the outcome of WP4 as well as the entire project.
The project was completed successfully, and all the objectives were met. The state-of-the-art review in software network technologies was completed, followed by a suitability analysis, scenario identification and definition of federated satellite/terrestrial virtualisation-capable network architectures. The architectures were implemented and validated in a lab environment using carefully selected use case scenarios. In parallel, the techno-economic analysis which was carried out, revealed and quantified significant cost savings and also opportunities for increased revenues for satellite service providers via the use of virtualisation technologies. A roadmap was eventually drafted, containing recommendations for the optimal uptake and exploitation of the proposed technologies.
