The Impact of SDN On MPLS Networks Adrian Farrel Juniper Networks afarrel@juniper

1. The Impact of SDN On MPLS NetworksAdrian FarrelJuniper Networksafarrel@juniper.net www.mpls2012.com

2. Agenda • Some Definitions Needed (SDN) • Why consider SDN? • SDN as a toolkit • Fine-grain programming • An interface to routing and policy • Enabling services • A programmable MPLS network

3. What do we mean by SDN? • Software • It’s all software! • We are looking for automation • Tools or applications • Driven or Defined • Does it matter? • Networks • Micro-management of forwarding decisions • Control of end-to-end paths • Whole-sale operation of network • Is it all about the buzz? • Shiny-thing Desparately Needed • $ome Dollars Now

4. What will we do with SDN? • Make our networks better • Provide cool services at lower prices • Reduce OPEX and simplify network operations • Enable better monitoring and diagnostics • Make better use of deployed resources • Converged services are the future • Converged infrastructure is the future

5. The SDN Toolbox • To a network, all configuration tools look like hammers • One size does not fit all • SDN is about engineering the routers to allow better tools to be designed and applied

6. MPLS Data Plane Programmability • Label stacking, popping, and swapping • MPLS as a cross-connect technology (NHFLE) • Prefix-to-label mapping (LFIB) • Integration with underlying data plane • Encapsulation rules • Data link addresses NHFLE LFIB In i/f, label Out i/f, label Prefix Out i/f, label NHFLE In i/f, label Pop IP Packet MPLS Packet MPLS Packet IP Packet

7. Applications and Protocols for MPLS Data Plane Programmability • An application is software that runs remotely • That demands a protocol and a data encoding • Element Management • IETF : SNMP/MIBs, Netconf/YANG • Proprietary : CLI, GUI, XML • Legacy : TL1 … • Network Management • Coordinated connection set-up is just coordinated element management • Control plane / data plane separation • Use an existing configuration protocol • IETF : GSMP (RFC 3292), ForCES (RFC 5810) • ONF : OpenFlow

8. Control Plane / Data Plane Separation • Support legacy / cheap devices • Experiment with new routing protocols • Integrate dynamic routing with static control • Avoid “complexities” of routing protocols Control plane SDN Programming Language Data plane

9. Functional Control at a Higher Level • Operators want to build and deploy services • “Make a pseudowire for me” • “Optimize my traffic loading” • “Provision a layer 3 VPN” • “Show me how my network is being used” • “Configure my data center” • “Manage security and policy” • “Provide service callendaring” • Needs a higher-level interaction with the network • Demands more sophisticated control of routers • Must integrate with standard routing features

10. Leveraging Existing Tools • New services and features for rapid deployment • There are plenty of existing tools • Leverage implemented and deployed protocols • We can put them together to enable high function SDN in MPLS networks • May need some extensions • Avoid long development cycles

11. BGP-LS to Extract Topology Information • Information about the network • Nodes and links • Link state • Up-to-date TE capabilities • Delay and other quality information • Status of existing LSPs / tunnels • Used for network monitoring, analysis, and planning • Critical input to path computation (e.g., via PCE) • Fundamental component unspecified in the PCE architecture • BGP-LS is a set of simple extensions to BGP • Client is any node listening to the IGP • For example an ASBR or a Route Reflector • Server can not be a very light-weight BGP implementation • Reduces dependency on IGP sniffing

12. Stateful PCE for Control of Services • Early work on PCE was stateless • PCE knows state of network • PCE does not recall anything about previous computations • PCE does not know about existing provisioned services • Except as described on new computation requests • Stateful PCE was always in the architecture • Retain information about provisioned LSPs • New extensions to PCEP • Allow explicit activation of LSPs from the PCE • Receive information from network about LSPs • Provides key components for bandwidth callendaring

13. Integrating the Components • IGP enhanced for TE and link quality • BGP-LS reports to PCE • PCE requests LSPs • Normal LSP signaling • LSP status reports PCE

14. Making New Tools Application Application • Can’t do everything with what have already • Interface to the Routing System (IRS) • A programmatic interface to routers Application Server IRS Client IRS Client IRS Protocol & Data Encoding Router OAM, Events and Measurement Topology DB IRS Agent Routing and Signaling Protocols RIBs and RIB Manager Policy DB Data Plane FIB 14

15. Enabling Services • Service enablement and turn-up is complex • Existing tools help with planning • Commissioning through scripts or work-plans • SDN can be a set of tools to enable services • L3VPN delivery • Data center interconnect • Bandwidth callendaring • Mult-layer connectivity and virtual links

16. Service Example : Multi-layer • SDN can coordinate multiple network layers • May both be MPLS networks • Involves many SDN components TEDB TEDB Traffic demand Service request BGP-LS PCE VNTM PCE IRS IGP-TE PCEP IRS Virtual Link RSVP-TE Policy OpenFlow & IRS IRS PCEP IRS GMPLS IGP-TE

17. Service Example : L3VPN with Callendaring • Which PEs to use? • How to connect PEs? • What load? When? • What redundancy? QoS? Security? • How to connect to the Internet? • Planned support for high bandwidth services DB Replication Content Streaming Data Transfer

18. Putting the Tools into the Box • SDN will possibly remain buzz and hype • Or maybe it will evolve into bickering between proponents of different solutions • Or it could become a comprehensive set of tools • Configuration tools • RIB and policy control • Topology and LSP management • Service enablement • Potential to enable a rich set of functions in future MPLS networks

19. SDN - Pandora’s Toolbox? Or a cornucopia of riches? A mess of overlapping tools and protocols with too many features and functions?

20. Questions? afarrel@juniper.net