Chapter 14 Ensuring Integrity and Availability

Chapter 14 Ensuring Integrity and Availability

CIA Triangle Confidentiality, Integrity and Availability: Three simple words with multiple meanings. Yet, one common thread unites them in the information environment to create a practical, organized approach to lowering the risks associated with managing data and systems.
Simply installing virus software is not enough you need to keep it up to date and educate your users. Watch and train users to notice and welcome them report the following symptoms:


•Unexplained file size increases
•Significant, unexplained system performance decline
•Unusual error messages
•Significant, unexpected system memory loss
•Periodic, unexpected rebooting
•Display quality fluctuations


When a user reports one of the symptoms or has heard of a virus ensure you don’t make them feel stupid for reporting otherwise they will not report it next time. As noted in security chapter 12 fifty perfect of your issues are human beings, I want the human factor on my side. Although you would like to tell them their latest issue was an “ID10T Error” hold your tongue and keyboard lashings. Mom always said, “If you don’t have something good about someone keep it to yourself”. Virus and Hoaxes users report use resources like SNOPES http://www.snopes.com/ or the knowledge database of the virus software you are running to verify legitimate viruses or Trojan viruses. A good rule of thumb/good practice is to check more than one resource to verify the information you are getting is correct. Once you have verified make sure to follow up with the user that has reported weather false or not and site your finds to them.


Fault-tolerant system goal is to prevent faults (malfunction) from progressing to failures (down) the following are items to insure you can reach your goal.


Physical environment, power techniques power backups (UPS's, Backup Generator, second power grid).


Topology and connectivity techniques dual internet/phone connections with failover techniques used in a router or firewall.


Server and storage techniques


Server mirroring is where you have an identical server in which one server continually duplicates the activities (data and transactions) of the main server.

Clustering servers is a technique that links multiple servers together to act as one server.


Storage RAID (Redundant Array of Independent [or Inexpensive] Disks) there are two differnet types hardware and software. Of the two hardware is faster and more reliable.


Different Raid Levels:
• RAIDZero means there is no redundancy the data is written across three drives. Fast however it is not fault tolerant.
• RAID level one disk mirroring the other automatically copying it to the second drive. SATA drives can write to both at the same time
• RAID Level one Disk duplexing two separate drives and two separate controllers.
• RAID Level 3 Disk Striping needs at least three drives data drive, data drive and a parity drive.
• RAID Level 5 -Disk Striping with Distributed Parity.


NAS (Network Attached Storage) is a specialized storage device group which provides centralized fault-tolerant data storage.


SANs (Storage Area Networks) Distinct networks of storage devices/servers that communicate directly with each other and other networks. Advantages are it is fast and fault tolerant. It uses special transmission methods using fiber-optic media and proprietary protocols.


Data backup Strategies:
Normal/Full: Backs up every file selected turns off A bit
Incremental: Backs up a bit files and turns off the A bit
Differential: Backs up a bit files - leaves A bit on
Copy: Backs up every file and leaves A bit on


Disaster Recovery Planning is a plan to ensure your organization is ready for a worst-case scenario disaster. Identifying and making people aware of who is on the disaster recovery team and the team members’ responsibilities. You will want contingency plans to restore and replace: Computer systems, Power, Telephony systems etc. To ensure your plan is solid stage an all systems to test (emergency outage) all systems to make sure they are working properly scheduled once a month, quarter, etc. Also when there are changes to hardware (Servers, Phones, Electrical, etc.) review your plan to ensure is has taken into account the changes.