It is possible to remove most of these limitations by combining our scheme with the existing Internet-backup-service model: A company would run the central server and bill users periodically. Backup would be done as per our scheme except that before abandoning a partner, a computer would upload the partner's data to the central site, where it would be stored temporarily. When the abandoned computer found a new partner, it would move its data from the central server to the new partner.
This model allows preserving backups even in the presence of
excessive downtime. Members would be billed at a basic rate similar to
our scheme but with surcharges for centrally storing data (charged
presumedly at the existing Internet-backup-services rate) and for
abusing partners. In essence, customers with good uptime would pay our
cheap rates while still being guaranteed a backup even if they exceed
the 2 week grace period or are down excessively, albeit at a slightly
higher price.