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[netCDF #ZDO-461948]: Data Integrity of NetCDF files transmitted across a network

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  • Subject: [netCDF #ZDO-461948]: Data Integrity of NetCDF files transmitted across a network
  • Date: Tue, 19 Apr 2011 17:05:19 -0600
> Full Name: Barry Steven Wilderman
> Email Address: address@hidden
> Organization: Boeing
> Package Version:
> Operating System:
> Hardware:
> Description of problem:
> 
> We are transmitting NetCDF4 files across a network. We would like to
> insure that the transfer does not corrupt the file contents.
> 
> I see in the NetCDF C interface guide that there is a function
> called nc_def_var_flether32 that does a checksum on a variable and a
> corresponding nc_inq_var_fletcher32 function that returns the checksum
> on the receiving end. Does this checksum also include the variable
> attributes?

No, that applies just to the data.

> 
> Do we have to use the fletcher32 algorithm or can we use one of our
> own choosing?

Of course you may use many different checksum algorithms, but the fletcher32 
one is the only one supported within netCDF-4. Other algorithms could include 
checksums on portions of your data (with the checksum stored as attributes in 
the file), or checksums of the entire file. 

I would also recommend you take a look at the remote data features of the built 
in DAP client of netCDF, since version 4.1. Perhaps you don't need to transmit 
your files in their entirety, but just make them available on a DAP server.

Thanks,

Ed


Ticket Details
===================
Ticket ID: ZDO-461948
Department: Support netCDF
Priority: High
Status: Closed