There are several ways that people might want to use Tahoe.  We're not necessarily committed to satisfying all of these use cases -- these are just possibilities.

Use Cases
||__name__||__number of nodes__||__administrative domains__||__node capacity__||__node availability__||__churn__||
||''friendnet''||2-10||many domains, but all trusted||mixed||mixed||low||
||''proprietary grid -- 1x upload''||2-30||one domain||uniform||high||low||
||''proprietary grid -- p2p upload''||2-50000||one domain for servers, many for clients||uniform||high||low||
||''hivecache''||10-1000||one domain, but not as well controlled||somewhat uniform||high||low||
||''Allmydata plus customers''||10-10,000||many||mixed||mixed||medium||
||''global grid''||any||many||mixed||mixed||high||

 * ''friendnet'': A group of friends want to share backup and files.
 * ''proprietary grid -- 1x upload'': A sysadmin, or Allmydata Inc. wants to backup data onto a set of servers.  The data is uploaded to the servers over a streaming protocol such as HTTP (using the Web API).
 * ''proprietary grid -- p2p upload'': A sysadmin, or Allmydata Inc. wants to backup data onto a set of servers.  The data is uploaded to the servers over the Tahoe distributed upload protocol.
 * ''hivecache'': A sysadmin wants to backup data onto hundreds of employee workstations.
 * ''Allmydata plus customers'': Allmydata, Inc. and its customers share a storage grid including the customer's computers.
 * ''global grid'': A large, diverse ecosystem of people and organizations who want a storage grid with extremely high reliability and availability.