Modern electronic proliferation of information has led to a tremendous quantity of data, sensitive and otherwise, being stored in electronic form, typically in non-volatile memory such as SSDs (solid state drives) and magnetic media. Deletion of sensitive information from electronic sources can be elusive, however. Many deletion operations merely reflag or designate areas corresponding to deleted data as available for new data, without actually overwriting. Direct access mechanisms, which access media on a location basis, rather then through a file system, can bypass the deletion flags and effectively access “deleted” data. Further, even when data is overwritten with new data, techniques exist to recover residual indications of previously stored data.
A media declassification device receives a media component such as an SSD or magnetic disk drive, and eradicates any remnants of sensitive data stored thereon by physical agitation and dismantling the media component. A cutting wheel or die rotates in close tolerance to an interior surface of a cutting chamber, and cutters or protrusions on the cutting wheel engage the media component against a leading edge of the cutting chamber for shearing and/or cutting fragments of the media component into the cutting chamber. A screen at an opposed side of the cutting chamber has apertures that limit a maximum size of particles passing out of the cutting chamber.
Configurations herein are based, in part, on the observation that it can be problematic to ensure complete erasure of data from storage media once the media has been taken out of service. Data security techniques often impose requirements of overwriting and unreadability for decommissioned media; in the case of governmental regulations governing sensitive or classified data, physical dismantling of media to a particle size deemed unreadable is required to render formerly classified data as “declassified.” Unfortunately, conventional approaches to media/drive declassification suffer from the shortcoming than conventional dismantling techniques for decommissioned media often employ a hammermill or similar approach for physical pulverizing of media storage devices. Such devices have alternating sized voids for passing pulverized pieces. It can be difficult to ensure that large sized pieces cannot pass into the waste stream; in other words, to ensure that all pieces in the stream are no larger than a minimum size.
The foregoing and other objects, features and advantages of the invention will be apparent from the following description of particular embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
Depicted below are several examples of a media declassification device according to configurations herein. Physical dismantling of the media device is shown, including severing fragments of the existing storage media and any accompanying enclosure, and further agitating the severed fragments into particles sufficiently small to be considered unintelligible and unreadable of the information formerly stored therein, and therefore appropriate for declassification. A sufficiently small size for declassification may vary according to an external standard, but is around 2 mm.
A sizing regulator 140 passes fragments 41 within a maximum particle size, meaning equal to or smaller than a size deemed unreadable, such as 2 mm. The agitator is responsive to mechanical actuation for fragmenting the storage media against a sizing regulator 140 including a sieved surface or entity. The sieved surface is rigid with apertures or perforations based on the maximum particle size. Severed fragments 41 of a sufficiently small size pass as particles 42 into a repository 150 for declassified waste. Not all severed fragments 41 may be sufficiently small for passage as particles 42. In contrast to conventional approaches, which merely pass all output from a hammermill, shredder and similar dismantling, the approach herein provides a cyclic pathway 145 for redirecting fragments 41 exceeding the maximum particle size back to the agitator for successive agitation. The sizing regulator 140 is disposed near the agitator based on a tolerance for further shearing the fragments and particles exceeding the maximum particle size. Sheared fragments continue agitation as the agitator grinds and shears in a close tolerance against the sieved surface, and surrounding enclosure, to ensure continual shearing of fragments until a sufficiently small particle size is achieved.
The sizing regulator 140 may be fulfilled by a sieving entity 240 having an array of apertures, where a tolerance is based on an interference between the agitator and the sieving entity for shearing the particles unable to pass the apertures. The sieving entity 240 has a mesh, screen or apertures with a screen size for effectively evaluating the severed fragments 41 for a size smaller than a maximum particle size. The output bin 150 catches passed particles 242 of the severed fragments 41 as declassified media particles if meeting the maximum particle size. Agitation continues the severed fragments 41 until smaller than the maximum particle size for passing as declassified media particles 42. The aggregated, comingled particles form benign disposal 244 material for waste or recycling.
Continuing to refer to the example of
A size of the severed fragments 41 is based on a feed speed and a rotation speed, and a size of the sieved particles 42 is based on an aperture size of the sieved surface. This remedies a problem in the prior art where initially severed or dismantled portions are too large to be considered unreadable. Initially “large” fragments 41 continue shearing until small enough to pass as particles 42. A further advantage of the cyclic, rotating agitator is actuation for severing the fragments of the storage media 21 and shearing the fragments 41 into particles 42 based on the same rotational movement.
The enclosure 22 has a screen 40 at an opposed side from the feed opening 14 with apertures sized based on the maximum particle size 43. The screen 40 is disposed adjacent the agitator 10 and aligned with the enclosure 22 for engaging the particles cut or sheared by the cutters 12. It should be apparent that the screen 40 is adapted to pass the particles 42 from the enclosure through apertures based on the maximum particle size, such that larger particles simply advance around the enclosure 22 for additional agitation and cutting until sufficiently small to pass through the screen 40.
The agitator 10, in the example configuration, takes the form of a cutting wheel or drum defining the plurality of cutters in an interleaving arrangement of protrusions, such that the interleaved arrangement defines the spacing D1, D2 based on the maximum particle size 43. The round cutting drum shape rotationally couples to a drive source, such that the rotating agitator is adapted to engage the media component 20 in a severing communication against the enclosure 22 as particles 42 disengaged from the media component 20 may be iteratively agitated in the enclosure until sufficiently small to pass through the screen 40. A tolerance 45 between the agitator 10 and the enclosure 22 allows cyclic travel and successive shearing against the enclosure 22 until broken into particles small enough to pass the screen 40. A variety of cutting drums may be considered based on an ability to shear or disengage appropriately sized particles in conjunction with an appropriate screen. Generally, the cutting drum exhibits a discontinuous blade structure such as the interleaved cutters 12, so as to avoid cutting a pattern of elongated strips of material.
A further consideration involves a downward force on the media component 20 for biasing it into a cutting engagement. A mechanical plunger may be employed in the chute 16 to force the media component against the agitator. Other suitable conveyance means may be employed for drawing the media component into engagement with the agitator and biasing the particles through the screen, such as a frictional roller 114 or conveyor, gaseous currents or low pressure bias (i.e. vacuum suction), magnetic and gravitational mechanisms.
While the system and methods defined herein have been particularly shown and described with references to embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.
This patent application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent App. No. 63/166,446, filed Mar. 26, 2021, entitled “MEDIA DECLASSIFICATION DEVICE,” incorporated herein by reference in entirety.
Number | Date | Country | |
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63166446 | Mar 2021 | US |