Each spiral track is composed of pits and lands that each reflect light differently. CD-ROM: (Compact Disk – Read Only Memory) Contain one spiral track Capable of storing between 650-700MB of data in total Appropriate for constant data (eg. music) DVD: (Digital Versatile Disk) Each track can hold 4.7GB of data A double-sided disk can contain four tracks Capable of storing 17GB of data in total Appropriate for standard definition feature films (ie. up to 576p) Blu-Ray: Each layer can hold 25GB of data A standard double-layered disk is capable of storing 50GB in total Triple-layered and quadruple-layered disks are available for Blu-ray XL drives Appropriate for high definition feature films (ie. up to 2160p) Cartridge and Tape Magnetic tape is encased inside cartridges, ranging from the size of a matchbox to a VHS tape. Extremely cost effective; only costs a few cents per gigabyte. The tape is a long strip of plastic coated in a thin layer of magnetic material. In 2017, IBM and Sony made a palm-sized magnetic tape cartridge that could hold 330TB of data. Securing Data Encryption/ Decryption Encryption: Process of encoding data in order to maintain confidentiality and security Algorithm or encryption key is required to encode data Decryption: Process of decoding data back to its original form Reverse algorithm or decryption key is required to decode and read data Symmetrical: Same key is required for encrypting and decrypting Usually used when the data is being sent across one computer/system so the key is not required to be shared Asymmetric: Requires a public key and a private key for decryption The public key can be shared The private key must not be shared at all Often used when transmitting across multiple computers Backup Storing/copying data to another permanent storage device. Prevents loss of data in the event that data is lost or damaged at its original location.
Each spiral track is composed of pits and lands that each reflect light differently. CD-ROM: (Compact Disk – Read Only Memory) Contain one spiral track Capable of storing between 650-700MB of data in total Appropriate for constant data (eg. music) DVD: (Digital Versatile Disk) Each track can hold 4.7GB of data A double-sided disk can contain four tracks Capable of storing 17GB of data in total Appropriate for standard definition feature films (ie. up to 576p) Blu-Ray: Each layer can hold 25GB of data A standard double-layered disk is capable of storing 50GB in total Triple-layered and quadruple-layered disks are available for Blu-ray XL drives Appropriate for high definition feature films (ie. up to 2160p) Cartridge and Tape Magnetic tape is encased inside cartridges, ranging from the size of a matchbox to a VHS tape. Extremely cost effective; only costs a few cents per gigabyte. The tape is a long strip of plastic coated in a thin layer of magnetic material. In 2017, IBM and Sony made a palm-sized magnetic tape cartridge that could hold 330TB of data. Securing Data Encryption/ Decryption Encryption: Process of encoding data in order to maintain confidentiality and security Algorithm or encryption key is required to encode data Decryption: Process of decoding data back to its original form Reverse algorithm or decryption key is required to decode and read data Symmetrical: Same key is required for encrypting and decrypting Usually used when the data is being sent across one computer/system so the key is not required to be shared Asymmetric: Requires a public key and a private key for decryption The public key can be shared The private key must not be shared at all Often used when transmitting across multiple computers Backup Storing/copying data to another permanent storage device. Prevents loss of data in the event that data is lost or damaged at its original location.
SUMMARY-Information-Systems-and-Databases.docx