Results of Cluster Rating experiment

Larry K8UT

On February 4th the N1MM Dev Team released an update containing an experimental Packet Cluster Rating feature. This feature ran for 7 days and reported 19,860 attempts by N1MM+ to connect to 675 Packet Cluster URLs. The Dev Team’s goal in this experiment was to determine whether desktop data collection could produce a valid cluster availability list.

FILTERS: Those 675 URLs were filtered to retain only 129 favorable sites.  Removed from the list were sites: with less than 10 successful connections; less than 75% successful connection rate; to localhost, 127.0 or 192.128 sites (internal LAN connections); to the reversebeacon backbone (which individual stations are not supposed to use).

GEOGRAPHY: To our surprise, location was a strong factor in identifying favorable sites. Sites that were popular on one continent were not used on other continents. Sites with high availability rates on one continent suffered from poor availability on other continents. For example, VE7CC.NET had a 94% success rate in NA, but only 76% from EU. DX.HU:9000 had 89% (EU), 77% (AS) and 100% (OC).

POPULARITY: Record totals by continents were: EU (9621), NA (7377), AS (1560), SA (618), OC (335), AF (120) and {surprise!} AN (0). A longer collection interval, or collecting during a major contest, might have produced better data from AF and OC. VE7CC.NET was the clear favorite with 25% of the filtered results – although all of its traffic originated in NA and EU. There were no filtered VE7CC records from the other continents. Unfortunately, the second most popular URL was the REVERSEBEACON.NET backbone, with 932 records – supporting the claim that these client connections to the backbone cause serious performance issues on the RBN network during major contests.

AVAILABILITY: The filtered list of 129 includes 46 that were available 100% of the time, and the average availability for all URLs was 93%. As already described, availability varied by continent. DXFUN.COM, for example, reported 96% (NA), 86% (EU) and 77% (SA). These variations are clearly not the fault of the cluster server, but due to the Internet infrastructure between the Ham’s QTH and the server site.

DOWNLOAD: If you would like to replace the default Telnet list in N1MM+ with this experimental list, you can download it from the N1MM+ Website’s >Downloads >Experimental Program Files folder. Copy the file to your local /users/…/Documents/N1MM Logger+/Export folder. In N1MM+, open the >Window >Telnet >Clusters tab. Click the [Edit List] button, and in the Edit Telnet List dialog window, click >File >Import. NOTE: The new file will overwrite your current cluster selection - write it somewhere before you import!


Finally - keep in mind that this is experimental. I’m still not sure how we’ll incorporate a verified cluster list into N1MM+.

-larry (K8UT)

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