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This is all! This entry says, paraphrased, "The eduroam authentication for the realm greatidp.aq works over RADIUS with TLS encryption and is handled by the service target "_radsec._tcp.eduroam.aq". Note that this does not replace your normal RADIUS uplink to your national server; this is only an additional hint to streamline international roaming.
Don't worry, RADIUS software knows how to interpret this further 
If you are curious though, the next section explains what all these entries mean.
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