Message-ID: <4BB29185.50602@jpl.nasa.gov>
Date: Tue, 30 Mar 2010 17:04:21 -0700
From: Robert Khachikyan <robertk@jpl.nasa.gov>
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To: Carey Noll <Carey.Noll@nasa.gov>
CC: "igs-dcwg@igscb.jpl.nasa.gov" <igs-dcwg@igscb.jpl.nasa.gov>
Subject: [IGS-DCWG-61] Re: [IGS-DCWG-58] Change in compression scheme at
  IGS data centers
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IGS-DCWG Mail      30 Mar 20:55:04 PDT 2010      Message Number 61
******************************************************************************

Author: Robert Khachikyan

Carey,

20-30% more compression over gzip or hatanaka+unix_compression?

This compression scheme is to be applied to rinex only or rinex+prods or ??

Regards,
--Robert

On 3/30/2010 11:24 AM, Carey Noll wrote:
> ******************************************************************************
> IGS-DCWG Mail      30 Mar 11:23:01 PDT 2010      Message Number 58
> ******************************************************************************
>
> Author: Carey Noll/CDDIS
>
>      Over the years we have discussed updating the compression
> scheme used within the IGS to a more modern utility. I would
> once again like to visit this topic. Of course any change
> such as this would have to be rolled out over time but, at
> the CDDIS at least, we are thinking about changing the
> compression used in older data sets and then migrating more
> recent data over time, closely coordinating with our various
> user communities. Any new method should be integrated (or
> freely available) in the OS of major platforms (Linux, UNIX,
> Windows, OS X). Staff here are recommending bzip. This
> utility is available on Linux, UNIX, and OS X releases and is
> available for free for Windows. We have seen an improvement in
> compression by 20-30% using bzip on our limited tests. I would
> be interested in any thoughts on this proposal as well as any
> other commonly available utilities that could be considered.
>
> Regards,
> Carey.
> -----
> Ms. Carey Noll
> Manager, Crustal Dynamics Data Information System (CDDIS)
> Secretary, ILRS Central Bureau
> NASA GSFC
> Code 690.1
> Greenbelt, MD 20771
> USA
>
> E-mail:  Carey.Noll@nasa.gov
> Voice: (301) 614-6542
> Fax: (301) 614-6015
> WWW:  http://cddis.gsfc.nasa.gov
>