NETWORK ARCHITECTURE MODELS

1. NETWORK ARCHITECTURE MODELS Xiao Chen Fall2009 CSc 8320

2. INDEX • Section One: Basic Introduction • Introduction • System Architecture • Communication Network • Section Two: Current Projects • IEEE 802.11b for “Automobile” Users • Peer-To-Peer Techniques for Data Distribution in Desktop Grid Computing Platforms • Section Three: Future Prospect • Improvement of P2P • References

3. INTRODUCTION • What is ‘Distributed Computing’? "Distributed" or "grid computing" in general is a special type of parallel computing which relies on complete computers (with onboard CPU, storage, power supply, network interface, etc.) connected to a network by a conventional network interface, such as Ethernet.

4. DISTRIBUTED COMPUTING • Difference This is in contrast to the traditional notion of a supercomputer, which has many CPUs connected by a local high-speed computer bus

5. DISTRIBUTED SYSTEM CATEGORIES • Multiple computer systems collaborating to deliver a single application • Can be broadly applied to high-performance computing (HPC) whereby multiple computers, commonly called clusters, collaborate to solve a single problem • Multiple applications collaborating together as a system • Can be broadly applied to application integration whereby multiple discrete applications receive a copy of “some” data and process the data accordingly. • Architecture depends on the category.

6. DISTRIBUTED SERVICE • Distributed Service depend on the system architecture and the underlying communication network. • In the upper level, system architecture is an abstract description of major components and their relation • In the lower level, network architecture specifies the communication facilities

7. SYSTEM ARCHITECTURE

8. CLIENT-SERVER ARCHITECTURES • Workstation-server model [Chow, 1997] • A work station may serve as a Stand-Alone computer or as a part of an overall network • Some workstations are Diskless Workstation, all file and boot services are supported by the network

9. CLIENT-SERVER ARCHITECTURES • Processor-Pool model • Most workstations are idling at any instance in time. • Collects all processing power in Processor Pool Server • Users access a virtual single computer system with intelligent terminals

10. GRID ARCHITECTURES • Grid computing is a form of distributed computing that involves coordinating and sharing computing, application, data, storage, or network resources across dynamic and geographically dispersed organizations. • A Grid architecture represents the blueprint by which all this is possible.

11. GRID ARCHITECTURES

12. GRID ARCHITECTURES • The Network Layer provides the connectivity for the resources in the Grid. • The Resource Layer contains all the resources that are part of the Grid, such as computers, storage systems, and specialized resources such as sensors. • The Middleware Layer provides the tools so that the lower layers can participate in a unified Grid environment. • The Application & Serviceware Layer includes all applications that use the resources of the Grid to fulfill their mission. It is also called the Serviceware Layer because it includes all common services that represent mostly application-specific management functions such as billing, time logging, and others.

13. PEER-TO-PEER ARCHITECTURES • In this model, end users share resources in a peer style, potentially acting as both CLIENT and SERVER

14. PEER-TO-PEER ARCHITECTURES • Advantages: 1. removes single point failure and associated performance bottlenecks 2. releases the network traffic overhead by providing service locally

15. PEER-TO-PEER CATEGORIES • Three different categories: • Centralized P2P systems • Decentralized structured P2P systems • Decentralized unstructured P2P systems

16. COMMUNICATION NETWORK

17. COMMUNICATION NETWORK • The existence of multiple computer systems in a distributed system implies the need to interconnect these computers • System components may be connected by point-to-point or multipoint communication channels

18. WIRED INTERFACES: ETHERNET • Family of local-area network (LAN) products covered by the IEEE 802.3 standard that defines CSMA/CD protocol

19. CSMS/CD PROTOCOL • CSMS/CD protocol stands for : Carrier Sense Multiple Access With Collision Detection • a carrier sensing scheme is used. • a transmitting data station that detects another signal while transmitting a frame, stops transmitting that frame, transmits a jam signal, and then waits for a random time interval before trying to send that frame again.

20. WIRED INTERFACES: ETHERNET • Three data rates are currently defined for operation over optical-fiber and twisted-pair cables: • 10 Mbps—10Base-T Ethernet • 100 Mbps—Fast Ethernet • 1000 Mbps—Gigabit Ethernet

21. SECTION TWO: CURRENT PROJECTS

22. Drive-thru Internet: IEEE 802.11b for “Automobile” Users • Ubiquitous network connectivity – anywhere, anytime – for mobile users and permanent access to the Internet • Cellular wide-area networks, such as GSM, GPRS, and UMTS, are expensive and slow.(about 100 kbit/s for GSM) • In contrast, WLANs offer only local coverage but provide shared gross data rates from 10 to 50 Mbit/s.

23. DRIVE-THRU INTERNET: IEEE 802.11B FOR “AUTOMOBILE” USERS • They have measured transmission characteristics for sending and receiving high data volumes using UDP and TCP in vehicles moving at different speeds that pass one or more IEEE 802.11 access points at the roadside. • We discuss possibilities and limitations for the use of scattered WLAN cells by devices in fast moving vehicles and provide an analysis of the performance that can be expected for the communication in such scenarios. Based on these observations, we discuss implications for higher-layer protocols and applications.

24. PEER-TO-PEER TECHNIQUES FOR DATA DISTRIBUTION IN DESKTOP GRID COMPUTING PLATFORMS • To date, Desktop Grid systems have focused primarily on utilizing spare CPU cycles, yet have neglected to take advantage of client network capabilities. • Leveraging client bandwidth will not only benefit current projects by lowering their overheads but will also facilitate Destkop Grid adoption by dataheavy applications.

25. PEER-TO-PEER TECHNIQUES FOR DATA DISTRIBUTION IN DESKTOP GRID COMPUTING PLATFORMS • Two approaches to Peer-to-Peer data sharing that could be adapted for volunteer computing platforms: • the highly successful BitTorrent Communication Network • Peer-to-Peer data center

26. SECTION THREE: FUTURE PROSPECT

27. IMPROVEMENT OF P2P • We are currently experiencing an up to 60-70% of Internet traffic which is contributed by P2P applications. • Problems • Scattered traffic • Increased network utilization • Degraded performance of other applications • Increased network operational costs

28. IMPROVEMENT OF P2P • Objective? • Design a framework so that ISPs and P2P can work together • Where are the difficulties? • ISPs do not disclose their network information for privacy concerns • P2P does not have sufficient information to determine network-aware peering relationships • Future Work? • Implementation!

29. REFERENCES • Jorg Ott, Dirk Kutscher, Drive-thru Internet: IEEE 802.11b for “Automobile” Users, Technologiezentrum Informatik (TZI), Universit¨at Bremen, 2004 • Fernando Costa1, Luis Silva1, Ian Kelley2, Ian Taylor, Peer-To-Peer Techniques for Data Distribution in Desktop Grid Computing Platforms, CoreGRID TR-0095*,August 30, 2007 • Ge, Z.; Figueiredo, D.R.; Sharad Jaiswal; Kurose, J.; Towsley, D.; Modeling peer-peer file sharing systems, INFOCOM 2003. Twenty-Second Annual Joint Conference of the IEEE Computer and Communications Societies. IEEE Volume 3, 30 March-3 April 2003 Page(s):2188 - 2198 vol.3 • Haiyong Xie, P4P: Proactive Provider Assistance for P2P, Yale University, 2007