Architectural Support for Internet Evolution and Innovation

Transcription

1 Architectural Support for Internet Evolution and Innovation George N. Rouskas Department of Computer Science North Carolina State University Joint work with: Ilia Baldine (RENCI), Rudra Dutta, Anjing Wang, Mohan Iyer (NCSU) Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.1

2 Outline Motivation: Challenges with Internet Architecture SILO: A Meta-Design Framework SILO as Research Tool: Cross-Layer Experimentation Summary and Demo Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.2

3 In Search of Next Generation Internet Early Pioneer Work NSF GENI NewArch (DARPA) SIGCOMM FDNA NSF FIND Pouzin Society Euro NGI Euro 4WARD Euro FIRE Asia Future Internet Forum Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.3

4 Challenges with Current Architecture App App App Transport Network Data Link Physical 1. Evolution: function-heavy protocols with built-in assumptions 2. High barrier to entry: for new data transfer protocols 3. Cross-layer design: lack of inter-layer interactions/controls Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.4

5 Protocol Evolution: Transport Several distinct functions: identify application endpoints (ports) e2e congestion control multi-homing (SCTP) reliability semantics (TCP, RDP, SCTP, etc) evolution of individual functions affects entire transport layer Lack of clear separation between policies and mechanisms window-based flow control vs. how window size may change prevents reuse of various components Built-in assumptions about IP addresses transition to IPv6, support for mobility difficult Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.5

6 High Barrier to Entry New data transfer protocols difficult to implement/deploy except for use-space Experimental network designs crucial for: gaining insight understanding protocol operation discovering new knowledge rooted in physical world Implementations on commodity HW/SW remain challenging: require modification of OS kernel involve significant expertise limit ability to play with network stack Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.6

7 Cross-Layer Design Cross-layer design a major research theme over last decade: wireless networks TCP congestion control optical networks (later) Adoption of ideas in operational networks quite slow: no interfaces for inter-layer interactions/cross-layer controls lack of experimental work reliance on simulation with invalid assumptions Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.7

8 Accommodating New Functionality Deploy half-layer solutions (MPLS, IPSec) layers become markers for vague functional boundaries Adapt existing implementation to new situations TCP over wireless/large bw/delay product networks Implement own UDP-like data transfer no reuse or kernel optimizations Abandon the old: new implementations for sensor networks Internet balkanization Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.8

9 Role-Based Architecture (RBA) [BFH 2003] New abstraction: organize protocols in heaps, not stacks Richer interactions among protocols flexibility Require new system-level implementations A B C RSH 1 RSH 2 RSH 3 Payload Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.9

10 Recursive Network Architecture (RNA) [TP 2008] Meta-protocol: generic protocol layer with basic services Each layer in stack appropriately configured instantiation Allows reuse, cleaner cross-layer interactions, dynamic composition MP 4 MP 3 MP 2 MP 1 Physical Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.10

11 Recursive Network Architecture (RNA) [TP 2008] Meta-protocol: generic protocol layer with basic services Each layer in stack appropriately configured instantiation Allows reuse, cleaner cross-layer interactions, dynamic composition MP 4 MP 3 MP 2 MP 1 Wireless Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.10

12 Recursive Network Architecture (RNA) [TP 2008] Meta-protocol: generic protocol layer with basic services Each layer in stack appropriately configured instantiation Allows reuse, cleaner cross-layer interactions, dynamic composition MP 4 MP 3 MP 2 MP 1 Optical Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.10

13 Layering As Optimization Decomposition Protocol layers integrated into mathematical framework [CLCD 2007] [LSS 2006] Global optimization problem: network utility maximization Decomposition into subproblems layering optimal modules (protocols) map to different layers interfaces between layers coordinate the subproblems Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.11

14 Layering As Optimization Decomposition Clean-state optimization layered network architecture optimal layering TCP/IP stack various representations of optimization problem different layered architectures (loose) coupling among layers cross-layer considerations Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.11

15 Our View Internet architecture houses an effective design But: it is not itself effective in enabling evolution New architecture must be designed for adaptability/evolvability New architecture must preserve/generalize layering SILO objective: design for change Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.12

16 What is Architecture? Fundamental elements/principles vs. design decisions Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.13

17 What is Architecture? Fundamental elements/principles vs. design decisions Diverse points of view FIND projects target: addressing, naming, routing, protocol architecture, security, management, economics, communication technologies (wireless, optical), Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.13

18 What is Architecture? Fundamental elements/principles vs. design decisions Diverse points of view FIND projects target: addressing, naming, routing, protocol architecture, security, management, economics, communication technologies (wireless, optical), Our definition: Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.13

19 What is Architecture? Fundamental elements/principles vs. design decisions Diverse points of view FIND projects target: addressing, naming, routing, protocol architecture, security, management, economics, communication technologies (wireless, optical), Our definition: it is precisely the characteristics of the system that does not change itself, but provides a framework within which the system design can change and evolve Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.13

20 Meta-Design Framework Obtain a meta-design that explicitly allows for future change Not a particular design or arrangement of specific features Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.14

21 Meta-Design Framework Obtain a meta-design that explicitly allows for future change Not a particular design or arrangement of specific features The goal is not to design the next system, or the best next system, but rather a system that can sustain continuing change Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.14

22 SILO Architecture Highlights Building Blocks: services of fine-grain functionality Design Principles: 1. Generalize traditional layer stack 2. Enable inter-layer interactions: knobs: explicit control interfaces 3. Design for change: facilitate introduction of new services 4. Separate control from data functions Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.15

23 Generalization of Layering Silo: vertical composition of services preserves layering principle Per-flow instantiation of silos introduces flexibility and customization Decoupling of layers and services services introduced at point in stack where necessary Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.16

24 Silos: Generalized Protocol Stacks App App App S1 S1 S2 Cross Service Tuning S4 S3 S3 Silo & Service Mgmt S5 S6 S6 Knobs S7 S8 S8 S7 S9 Composability Constraints Physical Layers Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.17

25 Inter-Layer Interactions (1) Knobs: explicit control interfaces adjustable parameters specific to functionality of service enable info exchange among services Algorithms may optimize jointly the behavior of services in a silo data interface Service knobs Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.18

26 Inter-Layer Interactions (2) Upward information passing Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.19

27 Inter-Layer Interactions (2) Downward information passing Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.19

28 Inter-Layer Interactions (2) Up-and-down information passing Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.19

29 Inter-Layer Interactions (2) Silo-wide optimization/calibration Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.19

30 Design for Change Architecture does not dictate services to be implemented Provide mechanisms to: introduce new services compose services into silos Ontology of services: describes service semantics function, data/control interfaces relationship among services relative ordering constraints Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.20

31 Ontology Networking Knowledge s 2 service s 1 m m 1,1 1,2 s 5 s m 4 4,1 application s 3 m m 1,1 3,1 m 1,2 m 2,1 m control agent 3,2 m2,2 m m 4,1 3,1 s 6 m 3,1 m 5,2 m 6,3 silos policies m m 6,1 6,1 physical layer method Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.21

32 Service Composition Constraints on composing services A and B: A requires B A forbids B A must be above (below) B A must be immediately above (below) B Negations, AND, OR Minimal set: Requires, Above, ImmAbove, NotImmAbove All pairwise condition sets realizable Forbids = (A above B) AND (B above A) Above = NOT Below Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.22

33 Service Composition Problem Given: a set of essential services application Obtain a valid ordering of these and additional services or, identify conflicts with constraints Simple composition algorithm implemented Ongoing research in formalizing the problem Input Output Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.23

34 The SILO Hourglass Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.24

35 The SILO Hourglass Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.24

36 SILO Software Prototype Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.25

37 Prototype Architecture Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.26

38 SILO As a Research Tool Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.27

39 SILO As a Research Tool Deploys in a slice Researcher brings: custom services tuning algorithms ontology updates Connect to measurement framework cross-layer protocol experimentation tool Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.28

40 Software Defined Optics Optical substrate can no longer be viewed as black box Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.29

41 Software Defined Optics Optical substrate can no longer be viewed as black box Collection of intelligent and programmable resources: Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.29

42 Software Defined Optics Optical substrate can no longer be viewed as black box Collection of intelligent and programmable resources: optical monitoring, sensing mechanisms amplifiers, impairment compensation devices tunable optical splitters configurable add-drop programmable mux-demux (e.g., adjust band size) adjustable slot size Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.29

43 Cross-Layer Interactions Impairment-aware RWA and network design Placement of optical sub-systems (converters, amplifiers, regenerators) Traffic grooming Inter-layer QoS and traffic engineering Optical layer multicast Multi-layer failure localization and recovery App App App Transport Network Data Link Physical Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.30

44 Summary Vision enable flexibility, evolution: design for change fine-grain, reusable services, explicit control interface enables experimentation, flexibility, community of innovation per-flow service composition (silos) ease of evolution, policies Framework provide architectural support to vision: constrained composition commoditize cross-layer interaction / optimization Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.31

45 Ongoing Efforts New research directions silos in the core and scalability policy enforcement through composition constraints (generalized) virtualization as a service Extend the prototype portfolio of reusable services optical testbed deployment breakable experimental net (BEN) Explore synergies with other (FIND) projects Architectural Support for Internet Evolution and Innovation GaTech, September 23, 2009 p.32