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Cabo: Concurrent Architectures are Better than One. Nick Feamster, Georgia Tech Lixin Gao, UMass Amherst Jennifer Rexford, Princeton. Today: ISPs Serve Two Roles. Role 1: Infrastructure Providers. Role 2: Service Providers.
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Cabo: Concurrent Architectures are Better than One Nick Feamster, Georgia TechLixin Gao, UMass AmherstJennifer Rexford, Princeton
Today: ISPs Serve Two Roles Role 1: Infrastructure Providers Role 2: Service Providers • Infrastructure providers: Maintain routers, links, data centers, other physical infrastructure • Service providers: Offer services (e.g., layer 3 VPNs, performance SLAs, etc.) to end users No single party has control over an end-to-end path.
Coupling Causes Problems • Deployment stalemates:Secure routing, multicast, etc. • Focus on incremental deployability cripples us • Shrinking profits and commoditization: ISPs cannot enhance end-to-end service • No single ISP has purview over an entire path “How do you think they're going to get to customers? Through a broadband pipe.. we have spent this capital and we have to have a return … there's going to have to be some mechanism for these people who use these pipes to pay for the portion they're using.” –Edward Witacre • Peering Tiffs: End-to-end connectivity is in the balance “As of 5:30 am EDT, October 5th, [2005], Level(3) terminated peering with Cogent without cause…even though both Cogent and Level(3) remained in full compliance …We are extending a special offering to single homed Level 3 customers. Cogent will offer any Level 3 customer, who is single homed to the Level 3 network on the date of this notice, one year of full Internet transit free of charge at the same bandwidth currently being supplied by Level 3. …”
Proposal: Concurrent Architectures are Better than One (“Cabo”) • The business entities that play these two roles may be the same in some cases • Infrastructure providers: maintain physical infrastructure needed to build networks • Service providers:lease “slices” of physical infrastructure from one or more providers
Similar Trends in Other Industries • Commercial aviation • Infrastructure providers: Airports • Infrastructure: Gates, “hands and eyes”, etc. • Service providers: Airlines BOS ORD SFO ATL • Other examples: Automobile industry
Communications Networks, Too! Two commercial examples • Packet Fabric: share routers at exchange points • FON: resells users’ wireless Internet connectivity Broker • Infrastructure providers: Buy upstream connectivity, broker access through wireless • Nomads: Users who connect to access points • Service provider: FON as broker
Application #1: End-to-End Services • Secure routing protocols • Multi-provider VPNs • Paths with end-to-end performance guarantees Today Cabo Competing ISPs with different goals must coordinate Single service provider controls end-to-end path
NYC Tokyo ATL Application #2: Virtual Co-Location • Problem: ISP/Enterprise wants presence in some physical location, but doesn’t have equipment there. • Today: Backhaul, or L3 VPN from single ISP • Cabo: Lease a slice of another’s routers, links
Challenge #1: Simultaneous Operation • Problem: Service providers must share infrastructure • Approach: Virtualize the infrastructure • Nodes (lessons from PlanetLab will help) • Links (previous lessons in QoS?) • Tomorrow’s talk on VINI • Cabo will exploit many of the same functions that are needed for VINI • Cabo philosophy: virtualization is the architecture
Challenge #2: Substrate • Problem: Service providers must be able to request/create physical infrastructure • Discovering physical infrastructure • Decision elements (cf. 4D proposal) • Creating virtual networks • Requests to decision elements (initially out of band), which name virtual network components • Instantiating virtual networks • Challenges include embeddingand accounting
Economic Questions • Being a service provider: a great deal • Opportunity to add value by creating new services • Infrastructure providers • Profit margins may be low • Back to CLEC/DSL battles? • Who will become infrastructure providers?
Partial Wish List • Router virtualization • Scheduling of node CPU, link bandwidth, etc. • Programmable software in each slice • Service providers will customize • Support for substrate • “Out-of-band” communication • Accounting features
Summary • ISPs are infrastructure + service providers --- Problematic • Deployment stalemate • Commoditization • Cabo: “Concurrent Architectures are Better than One” • Separate infrastructure from service providers • Applications • Multi-provider VPNs, end-to-end services and protocols, … • Challenges • Simultaneous operation • Bootstrapping More Information: http://www.cc.gatech.edu/~feamster/papers/cabo.pdf