Security provided by barriers is available with many differing degrees of safety. Choosing whether to have a permanent barrier or something that can be moved with relative ease depends on various external factors including safety access and the value of the item being safe guarded.
Active barriers create a secure environment by blocking a path or route but open or move to allow passage when necessary. A door or security barrier is active because it can be moved to allow access but keeps unwelcome visitors outside.
Passive barriers, such as a brick wall or a castle moat, are fixed structures designed to stop access. A passive barrier is relatively impenetrable and immovable. No manual or electronic action is required for the barrier to perform its function.
Choices for Security
Your choice of barrier is very much dependent on why you need it. Maximum security needs a higher ratio of passive barriers with minimum access via active secure barriers. If you are using barriers for information or direction, then active, movable barriers are the only option.