1 / 21

Comparative measurements of Internet traffic using cache-triangle

Comparative measurements of Internet traffic using cache-triangle. Serge A. Krashakov, Lev N. Shchur. Landau Institute for Theoretical Physics Chernogolovka, Russia {sakr,shchur}@landau.ac.ru. Cache-mesh. The problem definition. There is caching proxy-server in Chernogolovka (proxy.chg.ru)

idalia
Download Presentation

Comparative measurements of Internet traffic using cache-triangle

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. Comparative measurements of Internet traffic using cache-triangle Serge A. Krashakov, Lev N. Shchur Landau Institute for Theoretical Physics Chernogolovka, Russia {sakr,shchur}@landau.ac.ru

  2. Cache-mesh

  3. The problem definition • There is caching proxy-server in Chernogolovka (proxy.chg.ru) • There are several possible parents - FREEnet, RSSI, OSI - in Moscow; NLANR in USA • We want to minimize user requests latency time. We can send requests directly or forward to one of the parents. - Domains, as a rule, are not compact. Therefore static routing via huge access list is practically impossible. - AS based static routing is also hardly to manage - IP-routing is dynamic - Channel loading varies in time

  4. Fragment of netprobe database 193.233.46.0 681/ 682 1.0 1.0 www.chg.ru www-cache.chg.ru www.gnu.org.ru ikia.ru.ircache.net 545.4 6.0 sd.cache.nlanr.net 589.3 12.0 pb.cache.nlanr.net 594.0 9.0193.233.32.0 106/ 106 1.0 2.0 fortran.org.ru itp.ac.ru www.itp.ac.ru ikia.ru.ircache.net 343.7 5.9 sd.cache.nlanr.net 1054.7 12.0193.233.36.0 192/ 192 5.1 4.0 www.issp.ac.ru alpclub.ru ikia.ru.ircache.net 235.7 5.8193.232.212.0 383/ 385 62.5 6.0 www.rssi.ru www.rka.ru ikia.ru.ircache.net ikia.ru.ircache.net 3.8 1.0 pb.cache.nlanr.net 212.1 12.0 sd.cache.nlanr.net 293.1 21.0158.250.9.0 4/ 4 101.5 8.0 www.npi.msu.su optics.npi.msu.su www.grammy.ru ikia.ru.ircache.net 23.1 5.0 sd.cache.nlanr.net 213.0 20.0 bo.cache.nlanr.net 297.0 19.0140.221.9.0 12/ 12 200.2 9.0 www.globus.org www.mcs.anl.gov ftp.mcs.anl.gov uc.cache.nlanr.net 8.0 6.0 pb.cache.nlanr.net 12.2 6.0 bo.cache.nlanr.net 27.3 8.0 sd.cache.nlanr.net 67.0 9.0 ikia.ru.ircache.net 258.2 16.0194.94.42.0 46/ 123 230.1 15.0 www.springer.de science.springer.de link.springer.de uc.cache.nlanr.net 131.5 16.0 sd.cache.nlanr.net 193.6 22.0 ikia.ru.ircache.net 210.2 16.0 pb.cache.nlanr.net 1656.6 13.0198.9.9.0 2/ 2 254.5 10.0 www.nas.nasa.gov sv.cache.nlanr.net 1.2 4.0 uc.cache.nlanr.net 48.0 8.0 pb.cache.nlanr.net 55.5 8.0 sd.cache.nlanr.net 108.0 10.0 ikia.ru.ircache.net 262.5 13.5

  5. Support of ICMP RTT measurements, netprobe database and ICP v2 (with ICP_FLAG_HIT_OBJ) was introduced in Squid-1.1.19 (1997) • Using this algorithm permits: • automatically choosing shortest (RTT-wise) path to the source server • load balancing between alternative communication channels

  6. Proposed Squid modification Standard Squid Modification tpd <> tod top + tpd <> tod

  7. Suppose that we must choose between two or more strategies for caching 1. How can the strategies be compared to obtain the conditions under which some are preferable (more efficient, etc)? 2. Are the measurements reproducible ? 3. If so, what is the accuracy of the measurements? 4. Or, how long should the measurements be continied to attain the given accuracy, e.g., 5%? • Main difficulties: • natural characteristics of human activity • evolution of the network • instability of a path from one point (e.g., user) and another (e.g., server) • problem of resolution: Whole Internet? TLD? AS? Host? URL?

  8. Rewind & Replay(january-february 2000)

  9. The ratio of mean speed of the document retrieving from the Web for some top-level domains with and without cache mesh

  10. Cache triangle

  11. Total number of queries to the different TLD during three weeks of work of the cache-triangle in symmetric configuration N = TLD-2.34(5)

  12. Relative difference in the number of queries served by the Left-slave and by the Right-slave

  13. N = TLD-2.25(16) nl cz ca fi pt The total traffic served by the Left-slave () and by the Right-slave () for different domains.

  14. Relative asymmetry of the total traffic in symmetric cache-triangle configuration

  15. Average document size for the symmetric configuration

  16. Average document transfer speed in kbit/sec, served by symmetric cache-triangle configuration

  17. Average size of the documents served by the Left-slave server using cache-mesh and by the Right-slave server with the direct connection to the origins.

  18. The average document transfer speed in kbit/sec.

  19. The average document transfer speed in kbit/sec. (another data set after tuning configuration)

  20. Average transfer speed ratio with and without using cache-mesh

  21. Conclusions 1. Experimental approach for comparative measurements for different cache strategies or cache request routing was proposed. 2. Usefulnes of such measurements for tuning cache server configuration and cache-mesh optimization was shown.

More Related