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[aprssig] Tier 2 Status

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Wed Jun 21 23:57:55 UTC 2006

> -----Original Message-----
> From: Stan - N0YXV
> Posted At: Wednesday, June 21, 2006 6:35 PM
> Subject: Re: [aprssig] Tier 2 Status
> (Confused look on face)
> If anybody can use the core servers then whats the purpose of 
> Tier2? If the
> Tier1 servers go down we have nothing. If Tier2 goes down we 
> have a backup (Tier 1). To do it the other way around 
> wouldn't work. I mean if we crash Tier 1 there isn't a Tier 2 
> to fall back on. Maybe somebody can get the confused look off my face.

Actually, Tier 1 is not a backup for Tier 2.  Tier 2 servers feed their
data into Tier 1 like all other servers so that all data flows through
the Tier 1 core servers.

There are over 5,000 stations (IGates, clients, and servers) directly
connected to APRS-IS.  Simply put: if everyone tried to connect to the 3
core servers, the Tier 1 servers have neither the bandwidth to handle
that nor would they be able to "load-share" to 2 servers if one of the
servers goes down (maintenance, moves, etc.).  Because of the mesh
design of the core servers, the complexity of maintaining more than 4
core servers becomes unmanageable with each server run by independent
sysops and getting then necessary OC-3 pipes with high pps routers
donated is unlikely as well.

Tier 2 servers (both aprs2.net servers and other second tier servers)
provide a very important service to APRS-IS.  They offload a significant
(over 2/3) of the connections from the core servers.  This makes a very
reliable and effective APRS-IS for all to use.


Pete Loveall AE5PL
mailto:pete at ae5pl.net 

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