Storage devices like hard disks, USB thumb drives, and memory cards have become incredibly popular, but they're not immune to malfunctions. At some point, anyone might need to recover data from one of these devices.
Data recovery is the process of retrieving data from a damaged, corrupted, or inaccessible storage device, such as a hard drive, solid-state drive, or USB drive. The process involves using specialized software and hardware to scan the device for recoverable data, often in a forensically sound manner to prevent further damage. Data recovery can be performed on various types of devices, including computers, laptops, smartphones, and external storage devices.
Direct access storage devices (DASD) are either permanently installed or easily removable, and are often hard drives, either rotational or solid state. During system setup, any storage device designated as part of the system DASD is considered a fixed storage device.
The US government uses the Advanced Encryption Standard (AES) to protect sensitive data, a symmetric block cipher widely used globally in software and hardware. It's a must-have for government agencies to safeguard electronic data, computers, and networks.
Analog recording is a method of recording audio or video signals onto a physical medium, such as tape, by representing the voltage signals from a microphone or camera as continuous magnetic signals. This method has been used for various applications, including storing and playing analog audio, and was first employed in mechanical devices like the phonautograph and phonograph, which recorded sound in analog form.
Analog-to-digital conversion (ADC) is the process of transforming a continuously variable (analog) signal into a multilevel (digital) signal, preserving the signal's key characteristics.
The American National Standards Institute (ANSI) is the primary organization in the US that funds the creation of technical standards, working closely with business groups. ANSI also represents the US in international standardization organizations like ISO and IEC (IEC).
Archival storage in computing refers to storing data that is not currently being used but is retained for future reference or record-keeping purposes, often utilizing the same technology as backups.
Base two in mathematics refers to integers constructed from a string of zeros and ones, which is used extensively in digital computing due to the ease of representing ones and zeros with different voltage levels on an electrical device.
The conversion from decimal to binary involves a straightforward process of transforming numbers with a base of 10 into numbers with a base of 2. For example, the decimal number 1210 is equivalent to the binary number 1102.
The term "bit" refers to a single binary digit, which can be either 0 or 1, and is the fundamental unit of data storage in digital computers. It is often included in a data byte or word, but can also be used alone to control or read logic ON/OFF operations. In a binary integer, a single digit is also referred to as a bit.
The amount of field intensity that must be applied to a magnetic substance before its magnetic state may be altered; is measured in Oersteds.
Cohesion is the attractive force between adjacent material sections, particularly in solids and liquids. It's what keeps a piece of matter together, holding it in its entirety. This force is crucial in maintaining the integrity of a solid or liquid, and is a key factor in determining their physical properties.
When leveling land over a large area, the Earth's spherical shape must be taken into account. This results in a horizontal line not being perfectly level, causing the staff reading to be higher than expected, a phenomenon known as curvature correction.
A decibel is a unit of measurement that shows the relationship between two physical variables, like sound or electricity power, by taking the common logarithm of the power ratio and multiplying by 10. It's 0.1 of a bel.
A decibel is a measure of sound pressure that is equivalent to one-tenth of a bel, and represents a logarithmic ratio of two power or root-power values, with a one-decibel difference corresponding to a 10^1/10 power ratio.
In digital recording, sound pressure or video values are converted into discrete integers, which are then recorded. These integers represent the continuous variations in sound or video, and are written down as a sequence.
In digital-The process of converting digital signals to analog signals involves transforming signals with a limited number of possible levels (digital) into signals with an unlimited number of possible levels (analog).
A dropout is a signal loss caused by a clogged or faulty tape head, dirt, or other issues that increase the space between the head and tape. This can result in missing magnetic material, leading to a white spot or streak on a video playback, or a tainted tape or recorder in playback, indicating a disintegrating tape binder.
A package with a heat sink that extends beyond the package body, facilitating mechanical connection to a heat transfer structure, with terminals that can protrude from or be attached to any side of the package.
To encourage extensive data reuse, publishers may need to use various formats and structures supported by different platforms. Using the correct format simplifies data administration and repurposing, making it easier to reuse and share data.
The method of recording involves a tape that is slowly moving and helically wrapped around a quickly rotating disc with miniature record heads implanted inside it, taking up to 180 degrees or more, with the equatorial plane of the drum slightly tilted relative to the tape's position.
A method of establishing magnetic data storage uses horizontal magnetization of a hard disk drive, differing from the traditional vertical magnetization of the drive.
Magnetic particle inspection is a process that uses a magnetic current to locate flaws on the surface and sometimes under the surface of ferromagnetic materials, such as cracks, porosity, and weld defects.
The magnetization that remains in a ferromagnetic material after removing an external magnetic field is called remanence, remanent magnetization, or residual magnetism, which is referred to as the material being "magnetized".
Mistracking occurs when the read head's path doesn't match the magnetic tape track, affecting both longitudinal and helical scanning techniques. This causes playback issues, as the reading head must catch a specific proportion of the tape, and if it's off track, recorded data won't play, often due to malfunctioning audio or video equipment.
A packing slip is a document that lists all items included in a shipment, using SKU numbers, weights, measurements, and unit counts to ensure accurate order fulfillment.
When viewed at a small angle, typically through a transparent or translucent window in the cassette, the tape strands that are standing taller than the rest of the tape are referred to as "popped strands."
Print-Through is a type of distortion that occurs when analog information, such as music, is stored on tape and the signal patterns are transferred from one layer of tape to another, causing unwanted audio effects.
Quantization is a mathematical process that reduces a large set of data into a smaller set with limited components, often used in rounding or truncation.
Refreshing a computer or TV screen is necessary because these devices can't maintain a constant picture. To fix this, electron cannons continually redraw the image on the screen within the cathode ray tube (CRT), essentially reloading the picture data from memory.
System Restore is a tool that allows you to revert your Windows environment to a previous state, preventing the need to reinstall the operating system in case of an installation failure or data damage. It restores the system to the way it was before the backup.
Retensioning, also known as rejuvenating, is the process of redistributing stresses in a tape by emptying it onto a take-up reel and restarting it at a regulated tension and speed. This technique allows the tape to retain its optimal condition, eliminating the need for replacement. By redistributing the stresses, the tape is able to maintain its original properties, making it suitable for continued use.
A program that automatically tests DNNs on a set of target devices, edge nodes, and cloud resources to find the optimal partitions that boost DNN performance is known as S/N.
The signal-The signal-to-noise ratio (SNR) is a metric that compares the desired signal to background noise, calculated as the ratio of signal power to noise power, often expressed in decibels. A higher SNR indicates more signal than noise, with values above 20 dB recommended for data networks and 25 dB for voice networks.
Sticky-Shed syndrome is a condition where the binders in a magnetic tape degrade, causing the ferric oxide magnetizable coating to separate from the plastic carrier or the thinner back-coating to break down, rendering the tape unusable.
Tape with a sticky, sticky, or gummy surface is referred to as sticky tape. This type of tape has lost its magnetic coating due to hydrolysis, making it less magnetic than new tape. Alternatively, sticky tape can also refer to a magnetic tape that has accumulated resinous or greasy deposits on its surface, used to prevent moisture from setting onto tape media.
When a tape's polymer binder comes into contact with water or moisture, it degrades, causing the magnetic particles to become loose and the tape to become sticky, which can lead to friction and potentially result in the tape getting stuck or the magnetic particles losing their data.
Stress, in the context of tape, refers to the pressure it can withstand, measured in units such as pounds per square inch (psi). When tape is tightly wrapped on a reel, it can develop high interwinding stress, resulting from the force exerted by the tightly wound layers.
The substrate, typically made of PET, is the backing of the film and is thicker than the adjacent layer, assisting the thin and magnetic layer. This combination is commonly used in tape backings.
To solidify the adhesive on a magnetic tape, heat it for a limited time at a high temperature. This is a temporary solution for the sticky shed or sticky tape condition.
Tape noise is the high-The frequency noise seen on analog magnetic tape recordings is known as tape noise, a feature of all magnetic tape. However, it can be reduced by adjusting the tape composition to use smaller pigment sizes, which is more effective in cheaper cassettes that use iron oxide pigments, producing the highest levels of tape noise.
Data saved on tapes can be kept for decades if properly maintained in packs, which consist of tape coiled on a hub or spindle, or in tape reels with metal, plastic, or glass hubs and flanges.
The tape transport mechanism in a magnetic tape player or recorder refers to the system that plays and records the tape, handling and moving it, comprising various components such as the head, capstan, pinch roller, tape pins, and tape guide, working together to transport the tape around.
The thermal layer on tapes prevents them from heating up, but it can cause distortion and alter magnetic properties if the tape medium is exposed to heat.
In a helical scan recording, mistracking occurs when the track deviates from being perpendicular to the tape's edge, exceeding the scan angle of the helical recorder. This mismatch can cause mistracking, especially if the track angle and scan angle do not align.
Transcription involves copying data from one tape to another, either in the same or a different format, effectively making a complete copy of the original data. This process is sometimes referred to as refreshing, where data is transferred from an older cassette to a newer one using the same format, or as reformatting and converting, where data is copied into a new format.
The trapezoidal error occurs when a shift in the orientation of a track has been captured, potentially leading to mistracking.
Tape backup is a technique of transferring data from the main storage device to a tape cartridge, which can be done manually or automatically with the right software. This post covers the important terminologies to know about Tape Data Recovery, including data loss, noise, and preserving data in these tapes.