[aprssig] javaprs port that doesn't send a "keepalive" packet?

AE5PL Lists HamLists at ametx.com
Tue Mar 20 07:35:40 EDT 2007


> -----Original Message-----
> From: Tapio Sokura
> Posted At: Tuesday, March 20, 2007 1:34 AM
> Subject: [aprssig] javaprs port that doesn't send a "keepalive"
packet?
> 
>  From the small sample I've studied, javaprssrvr-servers seem to
output
> a #-prefixed idle packet every 20-30 seconds, at least on port 14580.
> Is
> there a way to disable these packets by using a different port or
> sending a specific kind of login command, for example?

No.  There are some sysops that have disabled the keep-alive for special
applications which they might contact you directly.  The keep-alives are
necessary to ensure the client has not disappeared (connection severed,
not disconnected) and to ensure the client doesn't disconnect thinking
the server has gone away (many client software have their own timers for
seeing something from the server).
 
> I'm asking because a simple, only txing, cell-phone based tracker
> accumulates most of the traffic from these idle packets. When you are
> charged for every byte transferred, you like to keep the transferred
> amount to a minimum. Would using UDP solve this?

No.  The UDP functionality is only for packet transfers -from- the
server to the client to reduce bandwidth requirements since that is the
direction where most packets flow.  Keep-alives on the TCP connection
are still used to ensure the client is still there.

73,

Pete Loveall AE5PL
pete at ae5pl.net






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