•The use a database of signatures which been gathered from various forms of Malware. These databases must be kept up to date to remain effectivity. Disk Defragmenter: •Constant editing and saving of files eventually leads to situation where the disk become fragmented. Files are no longer stored as contiguous entities. •Segments of files in many different areas of the disk, slowing down performance as the partial files be pieced back together by the OS before opening then, •This is especially true overtime. •The disk defragmenter utility will analyse the disk and optimise usage of disk blocks to improve performance once more Disk Repair: •The OS usually provides some disk checking/analysis and repair tools. •An example is the Windows chkdsk tool •They can check for “bad sectors”on the disk and can sometimes repair these or at least mark them as bad so they are no longer used. •Windows also provides a “Disk Clean up”tool which can help remove unwanted files, freeing up space. •Disk recovery is usually the remit of specialist commercial services
Backup Software: •Losing data can be bad but you could lose company fata •Accidents happen, users delete data by mistake •So, we need to ensure that we have tested and verified backupsas part of our ITSC policy •Verification checks data bit by bit to ensure the target and source match •Unverified backups are worthless •Commonly we have a backup plan which takes a regular full backup, maybe weekly or monthly •We also take Incremental Backupson intervening days •In this way we only ever lost one day of data if there is a failure on any given day •We keep backups off site too in case of catastrophe onsite •We test the restoration process regularly too •Backup software can allow scheduled backups to run automatically –perhaps using tape “magazines”which are loaded once a week. •Other environment backup to a mirrored system –so recovery can be done immediately. Very expensive •Windows offers a backup and restore utility tool as part of the OS –suitable to PC use. •Using Google or other cloud services, we don’t worry about backups too much these days.
File Compression: •File compression can be used to maximise disk usage, but there is performance overhead. •Compressed files must be decompressed before they can be read/edited •So, it is better to use file compression only for archived files that you do not access often •Or reserve file compression for data which you will transmit over the network –to save bandwidth Library Programs: •Developers like a challenge and sometimes like to write code from scratch •However, it is not usually beneficial to “reinvent the wheel”•So we use Library Programs–Code which has been developed and tested before •Libraries are collection of ready –made sub-routines that can be called by programs executing within the host file.