[CQ-Contest] RBN Announcement on FT8 Spotting

N4ZR n4zr at comcast.net
Tue Jun 12 09:35:38 EDT 2018

As some may be aware, we’ve been debating for some time about whether 
the RBN should handle FT8 spots.  A few weeks, ago, several prolific RBN 
nodes began spotting FT8 signals, using the combination of WSJT-X and an 
unreleased Aggregator, version 5.  The purpose of this limited Alpha 
test was to get a feel for the load and other implications of carrying 
FT8 spots on the RBN; it has been very revealing.

The most striking characteristic of FT8 spots is their sheer quantity. 
Here are some weekday statistics from one of the US testers:


CW 4294 14%

RTTY 69 0.22%

FT8 26318 86%

Total 30681


CW 4370 13%

RTTY 46 0.14%

FT8 29298 87%

Total 33714

Whether due to the startling popularity of the new mode, or to the 
ability to spot stations at 22 dB below the noise level, it seems 
obvious that adding FT8 spots to our spot flow could have a huge impact 
on the infrastructure of the RBN.  These numbers suggest that if only 
20-30 RBN nodes added FT8 spots, those spots could outnumber the total 
CW and RTTY spots being delivered by the 140-150 nodes currently active 
on the network, doubling the total required throughput.

We frankly don’t know whether the RBN servers will be up to the task, so 
we decided we had better find out before the fall contest season is upon 
us.  Accordingly, we are taking the following steps on a Beta test basis:

 1. Effective immediately, the RBN’s current spot feed
    (telnet,reversebeacon.net port 7000) will be repurposed to handle
    only CW and RTTY spots. telnet.reversebeacon.net port 7001 will be
    set up for FT8 spots only.
 2. Operators of “retail” DX clusters are encouraged to offer the option
    of RBN spots with and without FT8 spots, as they now often give
    users a choice between spot streams with and without “Skimmer”
    spots, and to advertise when they begin to carry FT8 spots
 3. A Beta test version of Aggregator Version 5 that can handle FT8
    spots received from WSJT-X will be made available on the RBN web
    site, along with instructions on how RBN node-ops can configure
    their nodes to spot FT8 on one or multiple bands.  Note, please,
    that doing so will not interfere with your ability to continue
    spotting CW and RTTY.

We will closely monitor how the RBN servers handle this new load, as 
more and more nodes begin sending FT8 spots.  We also reserve the right 
to take steps as necessary to protect the core mission of the RBN, 
including shutting off the FT8 stream on major CW and RTTY contest 
weekends or, in an extreme case, discontinuing spotting of FT8 
altogether.  Even in a worst case scenario, FT8 spots will continue to 
be carried by PSKReporter.

We hope we’re not doing this in a vacuum.  The RBN team has been 
collecting the views of contesters and DXers on this, and we think that 
we’re headed in the right direction.  Feel free to let us know what you 
think of this experiment.


The RBN Team (KM3T, N4ZR, PY1NB, SV3SJ, W3OA)

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