1 / 14

CDN Mechanisms

CDN Mechanisms. The Client-Server-Resource model for Content Distribution Networks of varying node dynamics and density. Similar network models: Grid, Peer-to-Peer, CDN. Grid. Computational GRIDs

byron-osborne
Télécharger la présentation

CDN Mechanisms

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CDN Mechanisms The Client-Server-Resource model for Content Distribution Networks of varying node dynamics and density Similar network models: Grid, Peer-to-Peer, CDN cdn mechs.ppt

  2. Grid • Computational GRIDs • basic layer for harnessing processing power by distributing massive computational tasks to numerous resources (compute cycles and data storage) over matching communication links. data archives clusters MPPs wide area workstations instruments cdn mechs.ppt

  3. More grids • Information and knowledge GRIDs • allowing access to dispersed information, and knowledge discovery and extraction from spread knowledge resources. They make use of cognitive techniques and tools such as data mining, machine learning, content semantics, ontology engineering, information visualisation and intelligent agents. • Grid technologies are also to be interpreted in a broad sense including technologies for Peer-to-Peer Computing (P2P) • using commodity hardware to enable the co-ordinated use of geographically distributed resources without central control. cdn mechs.ppt

  4. Peer-to-peer Network • Classic definition • "A type of network in which each workstation has equivalent capabilities and responsibilities. This differs from client/server architectures, in which some computers are dedicated to serving the others." [Webopedia] • Modern (ad hoc) definition • P2P is a class of applications that takes advantage of resources --storage, cycles, content, human presence-- available at the edges of the Internet. • P2P nodes must operate outside the DNS system and have significant or total autonomy from central servers… cdn mechs.ppt

  5. CDN • Content distribution networks are coordinated caching systems. • CDNs are a multi-million-dollar business already. cdn mechs.ppt

  6. Network Model HTTP server example.com ? A B HTTP server B GET http://example.com/foo HTTP server C A DNS-redirecting CDN DNS redirector Client http://example.com/foo cdn mechs.ppt

  7. Mechanisms • Deployment: where service is located ( • Cooperation: • Query routing • Consistency • Internal resource management: • Replacement • Prefetching • Selection • (based on dns, multicast, anycast, metrics) • request distribution • Server selection cdn mechs.ppt

  8. CA Scenarios Morpheus / P2P Node dynamics BL AKAMAI • Node dynamics: • Hosts close to backbone, dedicated, permanent, versus • PC close to network edge, part-time, eventual, transient • Node density • About 10K nodes (Akamai) • About 100K-1000K nodes &+ (gnutella, freenet, morpheus, etc.) Node density cdn mechs.ppt

  9. Organisation • Tree, grid or any other “organised” topology (CDN) • Mesh, small network topology (P2P) • E.g. map of the gnutella network  cdn mechs.ppt

  10. Content Distribution Networks Xweb Per overlay (garantee service, mgmt) Service Control None (Best-effort Service, No mgmt,...) Web OS, Active Services Web Manual Modifications Dynamic Programming Programmability cdn mechs.ppt

  11. RA mosaic Squid parent Deployment Mechanisms Spawn RA pc1 Squid DM Spawn avant RA parent pc2 Squid Deployment Manager @ Service Providers DM Spawn Resource Agent @ Resource Providers RA Solution: XWeb cdn mechs.ppt

  12. WWG/laColla • P2P environment for group collaboration • Reduced scale groups on a large scale network • Event distribution based group communication • Three mechanisms: • Event distribution • (to group members) • Group membership • Repository agents • (where history and documents are stored) • Simulation (JavaSim) The number and location depends on many factors cdn mechs.ppt

  13. A Distributed Magazine ... demand is an important+changing factor ... A Demand based Algorithm for Rapid Updating of Replicas Simulation (Network Simulator NS) cdn mechs.ppt

  14. Influence of the Document Validation/Replication Methods onCoop. Web Proxy Caching • Performance of cooperative web caching • schemes (hieracy, mesh, hybrid) with different doc. validation/replication methods (TTL, invalidation, pushing, etc.) • Cost: combination of factors • Response time • Bandwidth consumption • Number of stale docs Simulation (Network Simulator NS) cdn mechs.ppt

More Related