In the last two exercises, you used the Tag Browser to access a tag properties folder and modify its properties, and you used the shortcut menu to change the setting of the Questionable Data property. There is a distinct difference between these two methods of tag property modification.
When you use the Tag Browser to modify tag properties the changes are known as "configuration changes". When you use the shortcut menu to access a tag's properties folder or change a property such as "Questionable Data", the changes are known as operational changes.
The difference between the two mainly comes into play when you are working with a networked application that is running on multiple workstations, as each differently affects the manner in which the data is propagated throughout the network.
VTS employs a locking scheme for networked applications to ensure that another user cannot edit a locked resource item such as a file, tag, or page, thereby ensuring that only one user may edit a resource item at one time. Once a change has been made to the locked resource item, you can unlock the item, and VTS will send the updated data to all workstations running the application.
Operational changes do not use this locking scheme. Operational changes are mainly made by operators who need to control equipment immediately, as in the case of an emergency shutdown. Making operational changes means that the changes are made immediately to the resource item and are propagated to all other workstations running the application; however, if you are in the process of making an operational change, and another user locks the resource item to which you've made modifications, your operational changes will be lost. Any changes made by the user who now has a lock on the item will override your operational changes.
As a VTS developer, you should primarily use Remote Configuration and the VTS locking scheme when making changes to an application.
The VTS Developer's Guide contains further information on networked applications and operational versus configuration changes