1. Network Virtualization Nick Feamster, Georgia Tech Lixin Gao, UMass Amherst Jennifer Rexford, Princeton NSF NeTS-FIND PI Meeting

2. 2 Overview: Three Proposals Concurrent Architectures are Better than One –Applications of network virtualization –This talk (Overview): Potential benefits of virtualization, opportunities and challenges Diversified Internet Architecture –Metanetworks, substrate, and applications –Two talks: Technical support for virtualization and substrate Future Optical Internet Architectures –On-the fly creation of point-to-point links –Last talk

3. 3 Characteristics Virtualization –Multiple logical routers on a single platform –Resource isolation in CPU, memory, bandwidth, forwarding tables, … Programmability –General-purpose CPUs for the control plane –Network processors and FPGAs for data plane –Third-party software for routing and forwarding Separate the infrastructure from the routing architectures that run on top of it

4. 4 Research: Network Embedding Given: virtual network and physical network –Topology, constraints, etc. Problem: find the appropriate mapping onto available physical resources (nodes and edges) Many possible formulations –Specific nodes mapping to certain physical nodes –Generic requirements: three diverse paths from SF to LA with 100 MBps throughput –Traffic awareness, dynamic remapping, etc. –On-the-fly creation of links in the substrate

5. 5 Research: Substrate Design Problem: Brokering of physical infrastructure –Discovery: Discovering physical infrastructure Autodiscovery of components and topology Decision elements that configure components –Provisioning: Creating virtual networks Requests to decision elements (initially out of band), which name virtual network components Turner et al., Substrate Control Metanet –Creation: Instantiating virtual networks

6. 6 Proposal: Concurrent Architectures are Better than One (Cabo) Infrastructure: physical infrastructure needed to build networks Service: slices of physical infrastructure from one or more providers The same entity may sometimes play these two roles.

7. 7 End-to-End Services Multi-provider VPNs Paths with end-to-end performance guarantees TodayCabo Competing ISPs with different goals must coordinate Single service provider controls end-to-end path

8. 8 End-to-End Services Online BankingWeb Surfing RoutingSecure routing protocol (e.g., S-BGP) Lowest common denominator AddressingSelf-certifying addresses (optimized for persistence) Dynamic addresses (optimized for convenience) More Security More Complete Reachability Today: Deployment logjam –Deployment requires consensus and coordination Instead: Adopt pluralist approach –Determined service provider leases infrastructure and deploys technology end-to-end Example

9. 9 Application-Specific Networks Internal BGPLink-State Protocols DisseminationHierarchical, incrementalFlooding ComputationBGP-style decision processShortest Paths Better Scalability Faster Convergence Today: Optimize a single set of protocols Instead: Parallel deployment –Run multiple networks, each catered to specific applications Example

10. 10 Evaluation Platform: VINI XORP: control plane UML: environment –Virtual interfaces Click: data plane –Performance Avoid UML overhead Move to kernel, FPGA –Interfaces tunnels –Fail a link XORP (routing protocols) UML eth1eth3eth2eth0 Click Packet Forward Engine Control Data UmlSwitch element Tunnel table

11. 11 First Step: Independence from IP Solution: Forwarding should depend on MAC addresses in UML UML eth1eth3eth2eth0 Click Packet Forward Engine Control Data XORP (routing protocols) UmlSwitch element Tunnel table Forwarding cannot depend on IP New Routers and Protocols

12. 12 Parallel Deployment: Questions Guaranteeing global reachability –Do we need an end-to-end global reachability service? Proliferation of protocols and architectures –Is low barrier to entry a good thing for an architecture? Security –Should parallel deployment imply isolation? –If so, how to implement it?

13. 13 Economic Refactoring Infrastructure providers: maintain physical infrastructure needed to build networks Service providers: lease slices of physical infrastructure from one or more providers

14. 14 Also in Communications Networks Packet Fabric: share routers at exchange points FON: resells users wireless Internet connectivity Infrastructure providers: Buy upstream connectivity, broker access through wireless Nomads: Users who connect to access points Service provider: FON as broker Two commercial examples Broker

15. 15 Economic Refactoring: Challenges Being a service provider: a great deal –Opportunity to add value by creating new services Infrastructure providers –Can this enterprise be profitable? Who will become infrastructure providers? http://www.cc.gatech.edu/~feamster/papers/cabo.pdf Need to understand whether this refactoring would occur

16. 16 Can Other Industries Offer Clues? Infrastructure providers: Airports Infrastructure: Gates, hands and eyes, etc. Service providers: Airlines SFO ATL BOS ORD

17. 17 Summary Network virtualization General Challenges –Simultaneous operation –Substrate and interface Applications and Opportunities –Parallel deployment –End-to-end services and protocols –Economic refactoring

18. 18 This Talk Virtualization: An Overview –Architectural characteristics –General Challenges for Virtualization Resource Management –Example: Embedding Interface and Substrate Cabo: How Can Virtualization Be Useful? –Parallel deployment of routing architectures –Economic refactoring