Diese Präsentation wurde erfolgreich gemeldet.
Wir verwenden Ihre LinkedIn Profilangaben und Informationen zu Ihren Aktivitäten, um Anzeigen zu personalisieren und Ihnen relevantere Inhalte anzuzeigen. Sie können Ihre Anzeigeneinstellungen jederzeit ändern.

Information centric networking

2.315 Aufrufe

Veröffentlicht am

This PPT is about the Evolution From Circuits to Packets to Content in Information Centric Networking.

Veröffentlicht in: Ingenieurwesen
  • Als Erste(r) kommentieren

Information centric networking

  1. 1. Information-Centric Networking : The Evolution From Circuits to Packets to Content 02-04-2014 Jim Kurose School of Computer Science, University of Massachusetts, Amherst, MA 01003, United States
  2. 2. Contents 1. Introduction 1. Circuit Switching 2. Packet Switching 3. Information Centric Networks 2. Modeling Network of Caches 3. Analyzing Network of Caches 4. Locating Content and Caching Content 5. Fixed-point approximation method 6. Conclusion 7. References
  3. 3. Introduction • Erlang introduced the circuit-switched telephone network. • Fifty Years later, packet-switched networks introduced by Paul Baran. • And now its the era of Information Centric Networks (ICNs).
  4. 4. Circuit Switching • Calls are the basic unit of work in circuit switched networks . • The key performance metric is the call blocking rate. • A link’s call blocking probability is not independent of call blocking probability at other links.
  5. 5. Circuit Switching…
  6. 6. Packet Switching • Packets are the basic unit of work in Packet switched networks. • Elements of Packet Switching Networks 1. Packet Buffer 2. Buffer Overflow 3. Dropping • Two key performance metrics are packet delay and the throughput of packets • There are 2 type of performance analysis 1. Bottleneck queue in isolation 2. Fluid flowing from source to destination
  7. 7. Packet Switching…
  8. 8. Information Centric Networks • Requests for content issued by end users are the basic unit of work. • Each piece of content has a name and a custodian. • Each content router has a co-located cache commonly known as Transparent En-Route Caches(TERC).
  9. 9. Information Centric Networks…
  10. 10. Information Centric Networks… Node E will follow LRU algorithm to replace the existing item in its Cache
  11. 11. Modeling Network Of Cache • The richness and complexity results from the fact that each piece of content has a name i.e. a distinct identity. • In ICN models each piece of content i has a ‘popularity’ 풑풊. • Popularity 풑풊 follows the Zipf Distribution where it is directly proportional to 1/풊휶.
  12. 12. Modeling Network Of Cache… • IRM(Independent Reference Model) states that 풑풊 is independent of: o Time ‘t’ , o Previous request History for item ‘i’, o And request for other items ‘j’. • Least recently used (LRU) cache replacement is commonly assumed in ICN models. • In more static scenarios, cache content replacement is performed on the basis of measured or anticipated content popularity over a longer time scale .
  13. 13. Fixed-point approximation method • The rate of content requests at each node can be expressed as 풓풊,풗=흀풊,풗+ 풗′:풊휺푹(풗′;풗) 풎풊,풗′ • The miss rate for item i at content router 풗 can be expressed as 풎풊,풗=풓풊,풗(ퟏ − 풒풊,풗) • The hit probability for item i at content router 풗: 풒풊,풗=풉풊풕( 풓풊,풗 풋 풓풋,풗 , 풗 )
  14. 14. Locating Content and Caching Content • If all content routers can perform caching, it can be advantageous to selectively cache content along the download path, rather than at each and every content router. • Caching at more central nodes, cache hit rates can be improved over. • How to find content in cache Network? • Routing a content request along the shortest path from content requestor to content custodian.
  15. 15. Locating Content and Caching Content
  16. 16. Conclusion • Identified challenges in the modeling, design and analysis of information-centric networks. • Drawing analogies, as well as distinctions, from past research in both circuit-switched and packet-switched networks. • Finding content in a network of caches, managing the content in those caches.
  17. 17. References • [1]B. Ahlgren, C. Dannewitz, C. Imbrenda, D. Kutscher, B. Ohlman, A survey of information-centric networking, Commun. Magaz., IEEE 50 (7) (2012). • [2]A. Erlang, Solution of some problems in the theory of probabilities of significance in automatic telephone exchanges, in: E. Brockmeyer , H.Halstkom, A. Jensen (Eds.), The life and works of A.K. Erlang , Transactions of the Danish Academy of Technical Sciences (ATS),No. 2 1948. Originally published in Danish in Elektrotkeknikeren, vol. 13, 1917,. • [3]S. Eum, K. Nakauchi, M. Murata, Y. Shoji, N. Nishinaga, Catt: potential based routing with content caching for icn, in: Proceedings of the Second Edition of the ICN Workshop on Information-Centric Networking, ICN ’12, ACM, New York, NY, USA, 2012.
  18. 18. References • [4]E.J. Rosensweig, J. Kurose, A network calculus for cache networks, in: INFOCOM, IEEE, 2013. • [5]A. Girard, Routing and Dimensioning in Circuit-Switched Networks,1st ed., Addison-Wesley Longman Publishing Co., Inc., Boston, MA,USA, 1990. • [6]J.-Y. Le Boudec, P. Thiran, Network Calculus: A Theory of Deterministic Queuing Systems for the Internet, Springer- Verlag,Berlin, Heidelberg, 2001. • [7]R. Cruz, A calculus for network delay. i. Network elements in isolation, IEEE Trans. Inform. Theory 37 (1) (1991) 114–131. • [8]Y. Jin, W. Qu, K. Li, A survey of cache/proxy for transparent data replication, in: Second International Conference on Semantics,Knowledge and Grid, 2006, SKG ’06, November 2006.
  19. 19. Thank You.