[glue-wg] feedback on storage entities

[Maarten.Litmaath at cern.ch]

Hi all,

> In WLCG combinations of RetentionPolicy and AccessLatency have _extra_
> meaning that cannot be deduced from those attributes.
> 
> Such combinations are called Storage Classes:
> 
>     Custodial-Nearline == T1D0 --> disk managed by system
>     Custodial-Online   == T1D1 --> disk managed by client
>     Replica-Online     == T0D1 --> disk managed by client

In the "TnDm" notation 'n' indicates the guaranteed number of copies
on tape (or other high-quality media) and 'm' the guaranteed number
of copies on disk.

Cheers,
	Maarten