In this unit we are going to review a set of computer protection measures also known as countermeasures.

Transcription

1 1

2 In this unit we are going to review a set of computer protection measures also known as countermeasures. A countermeasure can be defined as an action, device, procedure, or technique that reduces a threat, vulnerability or an attack by eliminating or preventing it, by minimizing the harm it can cause, or by discovering and reporting it so that corrective action can be taken. In the next few slides we will explain these four kinds of countermeasure. 2

3 We will start with measures taken to cope with failures and physical disasters. The first measure that we can use in critical systems to ensure business continuity is redundancy in hardware, software and communications resources, replicating critical components and incorporating fail-safe mechanisms that, in case of a failure, let a back-up device resume the work without interruption (or within the maximum interruption time that a business can cope with). We can also use spatial diversity when introducing this countermeasure; for example, locating a back-up data center in another building so that if there is a fire where our main data center is located, the second one won t be affected and we can continue. Or say some kind of construction work breaks a communication cable, if we have a second cable following a different physical path or a wireless link, then we can route our traffic through these alternatives. 3

4 We should take measures to protect our hardware from physical risks. Installing a fire detection and suppression system, protecting the hardware from theft with an alarm system, building reinforced disaster resistant facilities or not building a data center where it might be affected by flood water, are a few examples. In the slide you can see a photo of the massive flooding in Thailand that affected the world supply of hard disks in

5 Information systems hardware works with electricity, and it can be very vulnerable to sudden loss of power, so we must protect it against power cuts. Uninterruptible Power Supplies (UPS) are used for short and sudden power interruptions. This method uses batteries to substitute the mains power supply and has switching mechanisms to ensure that the equipment receives constant and continuous power. The power is also stabilized, thereby avoiding any electrical problem that could damage the hardware. As the batteries used have a limited capacity, electric power generators should be included if we want to guarantee that the system will work during power outages that last any length of time. The most common generators are based on internal combustion engines. 5

6 A data backup refers to the periodic copying and archiving of computer data so it may be used to restore the original after a data loss event. The primary purpose is to recover data after its loss, whether this was caused by data deletion or corruption. A secondary purpose of backups is to recover data from an earlier time, according to a user-defined data retention policy, typically configured within a backup application. A plethora of storage media and services can be used for this purpose, among them, magnetic tapes, hard disks in different configurations (such as RAID, or Redundant Array of Independent Disks), optical storage, solid-state storage and remote backup services. This last option is also known as Cloud Backup or Backup-as-a-Service, where a company provides this type of service to end users. This can be considered as a form of cloud computing. Data backup is a practice that every computer user should apply, even individual users in their homes. In our technology-driven world there is a saying that there are only two kinds of people, those with data backup and those that, at some point in their lives, will regret not having it. 6

7 7