Il 16/12/2012 21:55, Rein Couperus ha scritto:
using several servers on 1 frequency generates a problem called 'hiden transmitter syndrome'. When you send a ping which is heard by DL9YCS-3, DL4OAH-8 and EA3GLL, they will all try to answer. When the frequency is busy each station will wait until the transmitting staion is ready. The problem is that DL9YCS-3 and DL4OAH-8 don't hear each other because they are too close to each other, so they are in the skip zone. PSKmail tries to solve the problem by: * Cloud marshalling (TM). All servers are supposed to be connected to the cloud on the internet, to a server called BigEar. Whenever a server activates PTT, is sends the status to BigEar. When other servers want to TX, they wait for the lock to disappear. Here is an example with DEBUG activated on PI4TUE:
As we have the congestion problem only in EU, the server checks its location before activating the connection.... This afternoon, there were network problems again in the data center which hosts the BigEar server. The hosting company has been under DDoS attack for the last 24 hours...
Hi ReinSo, if DDoS attack go away, in next tests I will get more "scattered" signal from different server?. I will try it.
PSKmail is the only system I know which goes to such great length of effort to make sure it behaves as a 'good citizen' on our shared bands. The alternative would be to jam large parts of the bands like winlink does it...
And this need a frequency list, an interface to prediction program, and a try for each station. If BigEar is working, it is a better solution.
We also have an experimental feature which makes all servers regularly send their frequency table to a server on pskmail.org. In future you will be able to ask any server to list the frequency table of the others. Meanwhile you can inspect the freq. tables stored by telnetting to pskmail.org port 8888, and entering the following command: ~info <SERVERCALL> Again an example: telnet pskmail.org 8888 Trying 220.127.116.11... Connected to pskmail.org. Escape character is '^]'. ~info PI4TUE FREQ:PI4TUE:Version 2.0.8 10148000,10148000,10148000,10148000,10147000, #0 This works provided the server you want to list is version 2.0.8 or greater, and it is connected...
There is a documentation of commands accepted from this telnet connection?Now client use a set of files, one for each server, with working frequencies.
Mantaining this set of files is a big and manual workIf there is a possibility to automatically mantain this files I can work on it.
Regards Franco Spinelli IW2DHW