Maintainable
Maintenance is the measure of the ability of an item to be retained in or restored to specified condition when maintenance is performed by personnel having specified skill levels, using prescribed procedures and resources, at each prescribed level of maintenance and repair.
Maintenance can also mean the measure of the time or maintenance resources needed to keep an item operating or to restore it to operational status. Maintainability may be expressed as the time to do maintenance (for example, maintenance downtime per sortie), as the staff required (for example, maintenance personnel per operational unit), or as the time to restore a system to operational status (for example, mean down time).
Maintenance is the physical act of preventing, determining, and correcting equipment or software faults. It includes all actions taken to retain the system/equipment/product in a useful serviceable condition or to restore it to usefulness/serviceability. Maintenance includes inspection, testing, servicing, classification as to serviceability, repair, rebuilding, and reclamation.
This requirement quantifies the time necessary to make specified changes to the product and to create an awareness of the maintenance needs of the product.
There may be special requirements for maintainability, such as maintenance will be performed by the end users. This sort of requirement will affect product development as there may be additional requirements for documentation and training.
The form and frequency of the intended release cycle must also be specified. For example, product updates may be downloaded from the internet by registered users.
Portable
The platforms or environments to which the new product will be ported, must be specified. This will quantify client and user expectations about the platforms on which the product will be able to run.
For example, the product may eventually be sold to the Korean market.
