The perimeter fence must first deter by its appearance. It should intimidate the inmate while conveying a message of humane security to the public. It must also detect. This may involve an alarm system that allows the security response team ample time to reach the attack area. A number of alarm methods can be used: buried cable, microwave, or fence-mounted systems. The system should have a low false alarm rate or provide a television system that allows an officer to examine the cause of the alarm. The fence must also delay any escape attempt. A perimeter fence may be defeated by climbing over it, going under it, or going through it. The fence should provide sufficient delay time to allow the response team to reach the attack area following the alarm detection. In deciding on a security fence, planners often focus too much on the barrier's cost. A fence having an initial low cost may require expensive security supplements, such as manned gun towers or patrol vehicles. The overall cost may surpass the cost of a more expensive but effective security fence.