SDN Software-Defined Networking

Transcription

1 SDN Software-Defined Networking The big picture: Rationale, comparison with current model, pitfalls Morten Engelsåstrø Chief NMS Architect Fixed Networks Telenor Norway

2 High-level definitions Software-Defined Networking (SDN) is an emerging network architecture where network control is decoupled from forwarding and is directly programmable Network Function Virtualization (NFV) is use of virtualization information technology to use standard hardware (processing, storage, networking) to implement Data Center (DC) and Telco network functionality. NFV and SDN are complementary technologies. NFV is a key enabler for SDN. The gains of using NFV increases with SDN use cases. 2

3 Network planes Forwarding planes processes and forwards packets Control plane contains the processes that control routing and switching protocols Management plane connects the node to the NMS site Management plane Month 0000

4 What is the need for a disruptive technology change in packet based network? Emerging mega-trends (e.g., mobile, social, cloud, and big data) in information and communication technologies (ICT) are commanding new challenges to future Internet, for which ubiquitous accessibility, high bandwidth, and dynamic management are crucial. However, traditional approaches based on manual configuration of proprietary devices are cumbersome and error-prone, and they cannot fully utilize the capability of physical network infrastructure Recent developments in ICT domain, for example, mobile, multimedia, cloud, and big data, are demanding for more convenient Internet access, more bandwidth from users, as well as more dynamic management from service providers. SDN is considered as a promising solution to meet these demands 4 00 Month 0000

5 Network requirements High resiliency Carrier grade availability Low reconvergence time Scalable Bandwidth Number of connected devices Secure Agile 5 00 Month 0000

6 Central orchestration vs SDN Central Orchestration (current model) Distributed forwarding plane Distributed control plane Centralized management plane Service Defined Networks Distributed forwarding plane Centralized control plane Centralized management plane Management Control Management Control Forwarding Forwarding 6

7 Central Orchestration System is master of all configurations in the network. No changes are done on network elements directly State is changed by North Bound Systems or internal UIs State is pushed to the network System database stores data for all active topology and services. It acts as a data store for the current network state. BSS/OSS NMS Network 7

8 NFV - innovative applications using standard hardware Definition NFV decouples SW from HW, so they can progress independently. Network functions can then run in virtual machines (VM) on commodity HW. 8

9 Why so much specialized hardware? NMS DNS RADIUS PS Core Netcentric FW NAT CDN +++ Route Reflectors Border Internet IP/MPLS Core DOCSIS CMTS Unified BNG IP/MPLS Edge (PE routers) Mobile P2P WiMAX BS IP/MPLS Access (PE routers) Fixed GPON xdsl/eth L2 Access Customer Connections CSS CSS Mobile

10 SDN Highlights Directly programmable: Network control is directly programmable because it is decoupled from forwarding functions. Agile: Abstracting control from forwarding lets administrators dynamically adjust networkwide traffic flow to meet changing needs. Centrally managed: Network intelligence is (logically) centralized in software-based SDN controllers that maintain a global view of the network, which appears to applications and policy engines as a single, logical switch. Programmatically configured: SDN lets network managers configure, manage, secure, and optimize network resources very quickly via dynamic, automated SDN programs, which they can write themselves because the programs do not depend on proprietary software. Open standards-based and vendor-neutral: When implemented through open standards, SDN simplifies network design and operation because instructions are provided by SDN controllers instead of multiple, vendor-specific devices and protocols. 10