Software Defined Networks Four Years Later. Quo Vadis, SDN? Ivan Pepelnjak Network Architect. ipspace.net AG

Transcription

1 Software Defined Networks Four Years Later Quo Vadis, SDN? Ivan Pepelnjak Network Architect ipspace.net AG

2 Who is Ivan Pepelnjak Past Kernel programmer, network OS and web developer Sysadmin, database admin, network engineer, CCIE Trainer, course developer, curriculum architect Team lead, CTO, business owner Present Network architect, consultant, blogger, webinar and book author Focus Large-scale data centers, clouds and network virtualization Software Defined Networking and NFV Scalable application design ipspace.net/about 2 ipspace.net 2015 SDN Four Years Later

3 What Is SDN?

4 SDN is the physical separation of the network control plane from the forwarding plane, and where a control plane controls several devices

5 SDN is the physical separation of the network control plane from the forwarding plane, and where a control plane controls several devices

6 SDN is packet forwarding done in software (on x86 platform)

7 SDN is packet forwarding done in software (on x86 platform)

8 SDN is whitebox switching (running software on third-party cheap hardware)

9 SDN is whitebox switching (running software on third-party cheap hardware)

10 SDN is network automation programmable access to network devices

11 SDN is network automation programmable access to network devices

12 SDN is an approach to computer networking that allows network administrators to manage network services through abstraction of lower level functionality

13 SDN is an approach to computer networking that allows network administrators to manage network services through abstraction of lower level functionality

14 Isn t That Just a Glorified Orchestration System?

15 SDN and NetOps is a lifestyle change

16 SDN Architectures

17 Device Provisioning Systems Controller is used to provision new devices Usually template-driven device configuration with automatic deployment Widely used in large-scale operations and service provider networks (residential CPE) Automatic configuration deployment supported by most networking vendors Network device Management / Policy plane Configuration / CLI / GUI / API Sample tools and products Ansible Arista ZTP Server Dell Fabric Manager Control plane Adjacent nodes Protocols Topology Static entries Routing and adjacency Forwarding table Data plane 17 ipspace.net 2015 SDN Four Years Later

18 Service Provisioning Systems Controller is used to provision new services Usually template-driven device configuration with automatic deployment Commonly used in large service provider networks Challenges Unreliable configuration deployment Software release dependencies Multi-vendor deployments Transactional consistency Sample tools and products Cloud orchestration systems Configuration automation tools (Ansible / Chef / Puppet) Tail-f NCS Cisco Prime Fulfillment MVSO, UCS Director Anuta Networks NCX Network device Management / Policy plane Control plane Adjacent nodes Configuration / CLI / GUI / API Protocols Topology Forwarding table Static entries Routing and adjacency Data plane 18 ipspace.net 2015 SDN Four Years Later

19 Routing and Forwarding Adjustment Controllers Controller is used to adjust forwarding paths Changes in device configuration (MPLS-TE tunnels or routing protocol metrics) Automatic creation of TE paths (example: PCEP) Adjustment of forwarding information (example: BGP) Challenges Limited by destination-only forwarding model Sample tools and products Cariden MATE Cisco PfR Quagga, ExaBGP Network device Management / Policy plane Control plane Adjacent nodes Configuration / CLI / GUI / API Protocols Topology Static entries Routing and adjacency Forwarding table Data plane 19 ipspace.net 2015 SDN Four Years Later

20 Centralized Control Plane (example: OpenFlow) B Out-of-Band Control-Plane Network A B B B B Control plane implemented in a central controller Network elements are dumb: packet forwarding only (incl. punt to controller) Controller has to reinvent all the wheels: routing protocols, LACP, LLDP, BFD Serious scalability limitations, hard to implement fast feedback loops Production-grade implementations use OpenFlow for exceptions or rely heavily on OpenFlow extensions B Prefix B B1 20 ipspace.net 2015 SDN Four Years Later

21 The SDN Toolbox

22 SDN Toolbox: Existing Tools Router Management / Policy plane NETCONF Configuration / CLI / GUI Control plane Static routes BGP OSPF SNMP PCEP Neighbor table Link state database IP routing table ForCES, BGP Flowspec, MPLS-TP Forwarding table Data plane 22 ipspace.net 2015 SDN Four Years Later

23 SDN Toolbox: Emerging Protocols OF-Config, XMPP, OVSDB, Puppet/Chef Router Management / Policy plane Configuration / CLI / GUI Control plane Static routes OSPF OnePK I2RS, OVSDB Neighbor table Link state database IP routing table OpenFlow Forwarding table Data plane 23 ipspace.net 2015 SDN Four Years Later

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26 Technology Is an Enabler, Not a Solution

27 We Need to Change the Model

28 Simplify Standardize Automate Abstract

29 Automate Everything

30 Start NOW

31 Stay in Touch Web: ipspace.net Blog: blog.ipspace.net SDN: ipspace.net/sdn Webinars: ipspace.net/webinars Consulting: ipspace.net/consulting 31 ipspace.net 2015 SDN Four Years Later