As we have detailed in the previous session, the data
stored by HTML5 Local Storage APIs face a lack of security.
However, this is not the unique trouble. When a user moves
from a machine to another, the data stored in the first used
cannot be retrieved. As a consequence, the data should be
synchronized following the user on his different equipments.
From these two points, security and availability, begins our
contribution. As illustrated in the figure 3