(unofficial) Metalink files for SeaDAS 6.2

[Ivan Shmakov]

I've put some Metalink files on the Web (see below for the
URI's), linking together the three official SeaDAS 6.2 mirrors:

ftp://samoa.gsfc.nasa.gov/seadas/seadas_6.2/
ftp://seadasuk.pml.ac.uk/seadas/seadas_6.2/
ftp://odyssey.fish.hokudai.ac.jp/SeaDAS_v6.2/

along with a single unofficial one. (Though please note that I
may revert my decision to maintain a publicly-accessible mirror
there, should there be too much traffic. Please also note that
the mirror in question is IPv6-only.)

The purpose of Metalink files is roughly as follows:

• some parts of the distribution appear to change only
occasionally (e. g., seadas_dem_modis.tar.gz); Metalink
contains all the necessary message digests (SHA-1, MD5, etc.)
to prevent an unnecessary download;

• download tools supporting Metalink typically allow for
multi-mirror downloads (see below for an example for Aria2);
when properly used, this will allow for the load to be
distributed among the links and mirrors themselves in an
optimal way;

• also, such tools may support simultaneous download via both
HTTP (FTP) /and/ P2P filesharing networks, such as BitTorrent
(indeed, Aria2 seems to do just that), eDonkey and GNUnet;

• thanks to the very same message digests, it becomes possible
to verify the distribution's integrity; should the Metalink
files also bear a digital signature, it would be possible to
verify that the downloaded distribution is exactly the same as
the one released, and not tampered by, say, an intruder.

http://gray.am-1.org/~ivan/metalink/seadas_6.2.seadas_linux.tar.gz.metalink
http://gray.am-1.org/~ivan/metalink/seadas_6.2.seadas_modisa.tar.gz.metalink
http://gray.am-1.org/~ivan/metalink/seadas_6.2.seadas_modist.tar.gz.metalink
http://gray.am-1.org/~ivan/metalink/seadas_6.2.seadas_processing_common.tar.gz.metalink
http://gray.am-1.org/~ivan/metalink/seadas_6.2.seadas_processing_linux.tar.gz.metalink

Usage example (command-line Aria2 agent):

bash$ aria2c -s11 -c -l seadas-download.log -- seadas_6.2.seadas_*.metalink

One could also specify HTTP and (or) HTTP-for-FTP proxy using
one or more of the following options:

--http-proxy=http://hostname.example.com:3128/
--ftp-proxy=http://hostname.example.com:3128/
--all-proxy=http://hostname.example.com:3128/

Where 3128 is the usual Squid caching proxy port (may just as
well be 80, 8080, or some other number.)

--
FSF associate member #7257