[OZAPRS] VKMAIL server observation

Richard Hoskin lhoskin at bigpond.com
Thu Apr 1 10:19:34 EST 2004

Hi Tony,

> -----Original Message-----
> From: ozaprs-bounces at marconi.ics.mq.edu.au [mailto:ozaprs-
> bounces at marconi.ics.mq.edu.au] On Behalf Of Tony Hunt
> Sent: Wednesday, 31 March 2004 11:15 PM
> To: ozaprs at marconi.ics.mq.edu.au
> Cc: hamish at cloud.net.au
> Subject: Re: [OZAPRS] VKMAIL server observation
> Yep .. Its confusing.. And yep its UI-Views interpretation of things..

[Richard Hoskin] 

UI-View does not present the raw RF data on the screen as you point out.
is the cut down APRS information that is displayed. From Memory Roger did
this to reduce confusion and clutter in the Monitor Window.

The Terminal Window is a more accurate account of the raw RF data but it
does do a few unusual things like add a '*' after each digi that the
has passed through rather than the last digi that the packet pasted

> Anyway thats that and now Ive got one for you Hamish looking at your
> monitor
> capture..  INETZ0 and INETZX ??  Ive seen these paths before on ISS
> traffic.. It was VK3UKF that was using them.. I emailed him and asked
> it was all about but he never replied.. He was using SGATE,INETZ0 on his
> downlink path from memory .. What are these paths all about ??

[Richard Hoskin] 

The INETZ0 etc is the IGate Zoning system we us in VK3.
You could look at it in a similar way to a mobile phone cell or a radio
voting system.

The Zoning system provides good (VK*) internet to RF traffic flow to the
full RF network while minimising the RF traffic levels.

We have one central Transmitter IGate (VK3SB) for the network and 3 (soon
be 4) Receive only IGates placed at selected locations (Zones) around the

The theory is that any station will never be more that 2 Hops from a
Receiving IGate so all mobile stations only need to use RELAY WIDE and all
home stations can use a direct path to the closest Receiving IGate. By
reducing the path length you reduce RF traffic levels.

The Transmitter IGate packets flow from roughly the centre to the edge of
the network. This means that a station at one end of the network will see
all traffic from the other end even though all paths are only local. (In
effect we are using the Internet as a backbone traffic network)

NOTE: It is Very Important that ONLY the Transmitter IGate is to use INETZ

As we are still to establish the final Receiving IGate there is a hole in
the IGate coverage in the North of the state which means all station in
north must use a minimum of 3 Hops to get to a Receiving IGate. Hence all
Mobiles need to use the path of RELAY,WIDE2-2 when travelling in the
In all other areas they only need to use RELAY,WIDE but that can get a bit
confusing so I advocate that all mobiles use RELAY,WIDE2-2 for now and all
Home station use a direct path to their local IGATE.

For APRS Messaging: the local Receiving IGates transmit as well as receive
local messages. So any message considered local (normally 1 or 2 hops from
the originator) will be sent to the originator via the local IGate. This
done to increase the reliability of APRS message reliability.

The system does produce some duplication of packets but as this is at the
edge of the network where RF traffic levels are low (normally 20 to 30
packets per 10 min) it is not a problem. Where the RF traffic level is
(Over 100 packets per 10 min) there is no duplication. Infact there is a
reduction in duplicated packets and RF traffic in the centre of the
as you do not see multiple hop packets bouncing around the RF digipeaters.

Any APRS packet duplication on the Internet is taken care of by the APRS
(Internet Servers) and IGates.

This design will really show it's efficiencies when we have the 4th
Receiving IGate running and all paths can be reduced to a maximum of 2

The education of all VK3 users and visitors to us the reduced paths will
a challenge.


ozaprs mailing list
ozaprs at marconi.ics.mq.edu.au

More information about the Ozaprs mailing list