What is claimed is:
1. An access control method for controlling access from an information processing apparatus which is connectable to a device requiring a first password authentication to a storage medium which requires a second password authentication, comprising:
a password generating step which automatically generates a password based on key information read from the device, when an authentication result of a password input to the information processing apparatus and a first password read from the device is correct; and
an access control step which enables access to the storage medium when an authentication result of the generated password and a second password read from the storage medium is correct.
2. The access control method as claimed in claim 1, wherein key information common to a group of users authorized to access the same storage medium is stored in the device which is accessible by each of the users belonging to the group.
3. The access control method as claimed in claim 1, wherein:
the storage medium is loaded into a storage apparatus which is connectable to the information processing apparatus;
said access control method further comprises:
an enciphering step which enciphers the generated password within the information processing apparatus based on an enciphering key read from the device, and transfers the enciphered password to the storage apparatus; and
said access control step deciphers the enciphered password based on an enciphering key read from the storage medium, and enables access to the storage medium when an authentication result of the deciphered password and the second password read from the storage medium is correct within the storage apparatus.
4. The access control method as claimed in claim 3, further comprising:
a first recording step which transfers the enciphering key from the information processing apparatus to the storage apparatus and records the enciphering key in the storage medium; and
a second recording step which deciphers the enciphered password transferred by said enciphering step into the second password within the storage apparatus, based on the enciphering key reproduced from the storage medium, and records the second password in the storage medium,
said first and second recording steps being carried out when setting the second password with respect to the storage medium.
5. A storage apparatus loadable with a storage medium which is accessible from an information processing apparatus which is connectable to a device requiring a first password authentication, said storage medium requiring a second password authentication, said storage apparatus comprising:
a receiving section which receives from the information processing apparatus a password which is generated when an authentication result of a password input to the information processing apparatus and the first password read from the device is correct, and is enciphered using an enciphering key which is generated based on key information from the device and read from the device; and
an access control section which enables access from the information processing apparatus to the storage medium when an authentication result of the enciphered password which is deciphered based on an enciphering key read from the storage medium and the second password read from the storage medium is correct.
6. The storage apparatus as claimed in claim 5, wherein key information common to a group of users authorized to access the same storage medium is stored in the device which is accessible by each of the users belonging to the group.
7. An information processing apparatus which is connectable to a device requiring a first password authentication and accesses a storage medium requiring a second password authentication, comprising:
a password generating section which automatically generates a password based on key information read from the device, when an authentication result of an input password and a first password read from the device is correct; and
an access control section which enables access to the storage medium when an authentication result of the generated password and a second password read from the storage medium is correct.
8. The information processing apparatus as claimed in claim 7, wherein key information common to a group of users authorized to access the same storage medium is stored in the device which is accessible by each of the users belonging to the group.
9. The information processing apparatus as claimed in claim 7, wherein:
the storage medium is loaded into a storage apparatus which is connectable to the information processing apparatus;
said information processing apparatus further comprises:
an enciphering section which enciphers the generated password based on an enciphering key read from the device, and transfers the enciphered password to the storage apparatus; and
said access control section deciphers the enciphered password based on an enciphering key read from the storage medium, and enables access to the storage medium when an authentication result of the deciphered password and the second password read from the storage medium is correct within the storage apparatus.
10. The information processing apparatus as claimed in claim 9, further comprising:
a first recording section which transfers the enciphering key from the information processing apparatus to the storage apparatus and records the enciphering key in the storage medium; and
a second recording section which deciphers the enciphered password transferred by said enciphering section into the second password within the storage apparatus, based on the enciphering key reproduced from the storage medium, and records the second password in the storage medium,
said first and second recording sections carrying recording operations when setting the second password with respect to the storage medium.
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 hole cutter including a cylindrical blade body with a rotational axis, wherein the blade body includes a plurality of blades and a plurality of grooves, each of the blades is arranged alternately with a corresponding one of the grooves around the rotational axis of the blade body, each blade includes a cutting edge formed at an end of the blade, and the blades include multiple types of blades with cutting edges that have different heights with respect to a predetermined reference plane perpendicular to the rotational axis.
2. The hole cutter according to claim 1, wherein the blades include at least first blades and second blades, the height of the cutting edge of each of the first blades is greater than that of the cutting edge of each of the second blades, and each of the first blades is disposed alternately with a corresponding one of the second blades around the rotational axis.
3. A hole cutter including a cylindrical blade body with a rotational axis, wherein the blade body includes a plurality of blades and a plurality of grooves, each of the blades is arranged alternately with a corresponding one of the grooves around the rotational axis, each blade has a cutting edge formed at an end of the blade, and the cutting edge of each blade includes:
an outer cutting edge, which is located closer to the outer circumference of the blade body and extends substantially in a radial direction of the blade body;
an inner cutting edge, which is located closer to the inner circumference of the blade body and extends substantially in the radial direction of the blade body; and
a stepped cutting edge, which is located between the outer cutting edge and the inner cutting edge and extends substantially in a circumferential direction of the blade body;
wherein the outer cutting edge of each blade has a point located at a radial outer position of the outer cutting edge, the inner cutting edge of each blade has a point between the inner cutting edge and the stepped cutting edge, the heights of the points of the inner cutting edges with respect to a predetermined reference plane perpendicular to the rotational axis are substantially equal for all blades, and the heights of the points of the outer cutting edges with respect to the reference plane are different among the blades.
4. The hole cutter according to claim 3, wherein the outer cutting edges include at least first outer cutting edges and second outer cutting edges, the point of each of the first outer cutting edges has a height substantially equal to that of the point of a corresponding one of the inner cutting edges, and the point of each of the second outer cutting edges has a height less than that of the point of a corresponding one of the inner cutting edges.
5. The hole cutter according to claim 4, wherein each of the blades with the first outer cutting edges is disposed alternately with a corresponding one of the blades with the second outer cutting edges around the rotational axis.
6. The hole cutter according to claim 3, wherein each of the stepped cutting edges is inclined with respect to the rotational axis at a first predetermined angle, and the inclination angles of the stepped cutting edges are substantially equal for all blades.
7. The hole cutter according to claim 6, wherein the height of the point of each outer cutting edge is determined in relation to a dimension of a corresponding stepped cutting edge in the circumferential direction of the blade body.
8. The hole cutter according to claim 3, wherein each of the outer cutting edges is located rearward from a corresponding one of the inner cutting edges in a direction in which the blade body is rotated to perform machining by the hole cutter.
9. The hole cutter according to claim 3, wherein each of the outer cutting edges is inclined with respect to the predetermined reference plane at a second predetermined angle, and the inclination angles of the outer cutting edges are substantially equal for all blades.
10. The hole cutter according to claim 3, wherein each of the inner cutting edges is inclined with respect to the predetermined reference plane at a second predetermined angle, and the inclination angles of the inner cutting edges are substantially equal for all blades.
11. The hole cutter according to claim 3, wherein each of the outer cutting edges is inclined with respect to the predetermined reference plane at a second predetermined angle, and each of the inner cutting edges is inclined with respect to the predetermined reference plane at an angle substantially equal to the inclination angle of a corresponding outer cutting edge.