1. A system comprising:
a front region comprising at least one layer;
wherein the front region comprises a mass of material characterized by having sufficient energy absorption properties to reduce stresses caused by an impact
wherein the impact has an impact energy of an impact projectile hitting the front region; and a back region comprising at least one layer including a chemically strengthened glass characterized by having
a surface compression of at least 100,000 psi and
a compression case depth of at least 600 microns.
2. The system of claim 1, wherein the chemically strengthened glass is formed by chemically strengthening a prior glass having a composition including Li2O in an amount ranging from 3 to 9 weight % and Al203 in an amount ranging from 7 to 30 weight % and SiO2, and an annealing point temperature of at least 580\xb0 C. prior to chemical strengthening.
3. The system of claim 1, wherein the chemically strengthened glass is formed by a method comprising immersion of the prior glass in a mixed potassium and sodium ion salt bath, containing less than 50 mole % sodium salt, at a temperature ranging from 450\xb0 C. to below an annealing point temperature.
4. The system of claim 1, wherein the back region consists of a single layer.
5. The system of claim 1, wherein the chemically strengthened glass is characterized by having a compressive stress of at least 30,000 psi at 50 microns below a surface of the glass.
6. The system of claim 1, wherein the chemically strengthened glass has a compression case depth of at least 1000 microns.
7. The system of claim 1, wherein the front region includes a polymeric layer.
8. The system of claim 1, wherein the impact projectile is a bullet.
9. The system of claim 1, wherein the impact projectile is a four pound gel mass.
10. A method for making a system, comprising:
fabricating a plurality of layers through bonding them together to form a system including a front region comprising at least one layer;
wherein the front region comprises a mass of material characterized by having sufficient energy absorption properties to reduce stresses caused by an impact,
wherein the impact has an impact energy of an impact projectile hitting the front region, and
a back region comprising at least one layer including a chemically strengthened glass characterized by having
a surface compression of at least 100,000 psi and
a compression case depth of at least 600 microns.
11. A method for using a system, comprising:
installing the system as a component in an article of manufacture, the system including
a front region comprising at least one layer
wherein the front region comprises a mass of material characterized by having sufficient energy absorption properties to reduce stresses caused by an impact,
wherein the impact has an impact energy of an impact projectile hitting the front region; and
a back region comprising at least one layer including a chemically strengthened glass characterized by having
a surface compression of at least 100,000 psi and
a compression case depth of at least 600 microns.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method of authenticating a host system by a hard disk drive accessed by the host system, the method comprising:
determining whether authentication information received from the host system is identical to authentication information stored in the hard disk drive; and
blocking access of the host system to the hard disk drive until the hard disk drive is turned off the authentication information received from the host system is not identical to the authentication information stored in the hard disk drive.
2. The method of claim 1, further comprising:
recording an authentication failure count if the authentication information received from the host system is not identical to the authentication information stored in the hard disk drive; and
rejecting access from the host system if the authentication failure count is greater than a predetermined number.
3. The method of claim 2, wherein a runtime is recorded at the same time as the authentication failure count is recorded, and rejecting access from the host system if the authentication failure count over a predetermined time period before an accumulative runtime is greater than the predetermined number.
4. The method of claim 3, wherein the authentication failure count and the runtime are recorded in a maintenance cylinder of the hard disk drive.
5. The method of claim 1, further comprising transmitting an authentication request from the host system to the hard disk drive.
6. The method of claim 5, wherein the authentication request is sent to the hard disk drive by way of a security unlock with customized command.
7. The method of claim 1, further comprising:
the host system forming and transmitting the authentication information to the hard disk drive when the hard disk drive accesses the host system; and
the hard disk drive storing the authentication information transmitted from the host system in a maintenance cylinder.
8. A method of authenticating a host system by a hard disk drive accessed by the host system, the method comprising:
forming authentication information, wherein the host system forms the authentication information based on information read from the hard disk drive;
transmitting the authentication information to the hard disk drive when the hard disk drive accesses the host system for a first time;
storing the authentication information transmitted from the host computer for the first time in a maintenance cylinder, which can be accessed only by the hard disk drive.
9. The method of claim 8, further comprising:
determining whether authentication information received from the host system is identical to authentication information stored in the hard disk drive; and
blocking access of the host system to the hard disk drive until the hard disk drive is turned off if it is determined that the authentication information received from the host system is not identical to the authentication information stored in the hard disk drive.
10. The method of claim 9, further comprising:
recording an authentication failure count if the authentication information received from the host system is not identical to the authentication information stored in the hard disk drive; and
rejecting access from the host system if the authentication failure count is greater than a predetermined number.
11. The method of claim 10, wherein a runtime is recorded at the same time as the authentication failure count is recorded, and rejecting access from the host system if the authentication failure count over a predetermined time period before an accumulative runtime is greater than the predetermined number.
12. The method of claim 11, wherein the authentication failure count and the runtime are recorded in a maintenance cylinder of the hard disk drive.
13. The method of claim 8, further comprising transmitting an authentication request from the host system to the hard disk drive.
14. The method of claim 13, wherein the authentication request is sent to the hard disk drive by way of a security unlock with customized command.
15. At least one computer readable medium storing instructions that control at least one processor to perform a method of authenticating a host system by a hard disk drive accessed by the host system, comprising:
determining whether authentication information received from the host system is identical to authentication information stored in the hard disk drive; and
blocking access of the host system to the hard disk drive until the hard disk drive is turned off if the authentication information received from the host system is not identical to the authentication information stored in the hard disk drive.
16. The recording medium of claim 15, wherein the method further comprises:
recording an authentication failure count and a runtime if the authentication information received from the host system is not identical to the authentication information stored in the hard disk drive; and
when there is an authentication request from the host system, checking the authentication failure count and the runtime, and rejecting the access request of the host system if the authentication failure count over a predetermined time period before a cumulative runtime is greater than a predetermined number.
17. The recording medium of claim 15, wherein the method further comprises:
recording an authentication failure count if the authentication information received from the host system is not identical to the authentication information stored in the hard disk drive; and
rejecting access from the host system if the authentication failure count is greater than a predetermined number.
18. At least one computer readable medium storing instructions that control at least one processor to perform a method of authenticating a host system by a hard disk drive accessed by the host system, comprising:
forming authentication information, wherein the host system forms the authentication information based on information read from the hard disk drive;
transmitting the authentication information to the hard disk drive when the hard disk drive accesses the host system for a first time;
storing the authentication information transmitted from the host computer for the first time in a maintenance cylinder, which can be accessed only by the hard disk drive.
19. The medium of claim 18, further comprising:
determining whether authentication information received from the host system is identical to authentication information stored in the hard disk drive; and
blocking access of the host system to the hard disk drive until the hard disk drive is turned off if it is determined that the authentication information received from the host system is not identical to the authentication information stored in the hard disk drive.
20. The medium of claim 19, further comprising:
recording an authentication failure count if the authentication information received from the host system is not identical to the authentication information stored in the hard disk drive; and
rejecting access from the host system if the authentication failure count is greater than a predetermined number.
21. The medium of claim 20, wherein a runtime is recorded at the same time as the authentication failure count is recorded, and rejecting access from the host system if the authentication failure count over a predetermined time period before an accumulative runtime is greater than the predetermined number.
22. The method of claim 21, wherein-the authentication failure count and the runtime are recorded in a maintenance cylinder of the hard disk drive.
23. The method of claim 18, further comprising transmitting an authentication request from the host system to the hard disk drive.
24. The method of claim 23, wherein the authentication request is sent to the hard disk drive by way of a security unlock with customized command.