c11.ppt

Distributed Systems 1 Chapter 11: Advanced Distributed Systems 1960 1970 1975 1980 1985 1990 1995 2000 * * Email * LAN * TCP/IP * * WWW * XML * PC cluster * Crays * MPPs * main frame * HTML * P2P computing * Grid computing * XEROX PARC * Web service * mini compute r * PCs * WS cluster * PDAs * workstatio n * high performen ce * Pervasive computing * IBM * Parasitic computing models Distributed Systems 2 puting ? Def 1 : “ A class of applications that take advantage of resources (., storage, cycles, content) available at the edge of the . ”? Edges often turned off, without permanent IP addresses, etc. ? Def 2: “ A class of decentralized, self- organizing distributed systems, in which all or munication is symmetric. ”(IPTPS ’ 02) ? Lots of other definitions that fit in between Distributed Systems 3 Applications: Computing ? Examples: ******@Home , UnitedDevices , ******@home, many others ? Approach suitable for a particular class of problems. ? Massive parallelism ? Low putation ratio ? Error tolerance, independence from solving a particular task ? Problems: ? Centralized. ? How to extend the model to problems that are not massively parallel? ? Ability to operate in an environment with limited trust and dynamic resources Distributed Systems 4 Applications: File sharing ? The ‘ killer ’ application to date ? Too many to list them all: Napster , FastTrack ( KaZaA , iMesh ), Gnutella ( LimeWire , BearShare ), , BitTorrent , etc ? Decentralized control ? Building a (relatively) reliable, data-delivery service using a large, heterogeneous set of ponents. TB/day on average Bytes transferred ~300,000 Number of unique files ≥ 10,000 Number of local users 230,000/day Number of download sessions FastTrack ( Kazaa ) ,2003 Distributed Systems 5 Applications: Content Streaming ? Streaming: the user ‘ plays ’ the data as as it arrives ? Examples:Pplive , SplitStream , etc source Oh, I am exhausted! C