Method of authenticating a consumable

1. A method of generating an authentication code for a consumable, comprising:

assigning an identification number to said consumable;

processing an input including at least said identification number, using a first algorithm, to generate a preliminary number different from said identification number; and

compressing said preliminary number using a non-hash compression only algorithm, different from said first algorithm, that utilizes said identification number to generate an authentication value for use in authenticating said consumable, said non-hash compression only algorithm comprising a masking process utilizing said identification number,

wherein said masking process comprises dividing said preliminary number into a number of groups of bits corresponding to a number of bits in said identification number, each group of bits corresponding to a particular bit in said identification number, selecting one or more groups of bits based upon a state of said particular bits in said identification number, and determining from each selected group of bits at least one bit of said authentication value.

2. The method of claim 1 , wherein said first algorithm is a hashing algorithm.

3. The method of claim 2 , wherein said preliminary number is an output digest of said hashing algorithm.

4. A supply item that contains a supply of imaging substance, said supply item comprising a memory having a plurality of memory locations that store:

a first number of bits representing an identification number associated with said consumable;

a second number of bits representing a preliminary number generated based at least in part on said identification number using a first algorithm, said preliminary number being different from said identification number; and

a third number of bits representing an authentication code generated by compressing said preliminary number using a non-hash compression only algorithm, different from said first algorithm, that utilizes said identification number, said third number of bits being less than said second number of bits, said non-hash compression only algorithm comprising a masking operation utilizing said first number of bits,

wherein said masking process comprises dividing said preliminary number into a number of groups of bits corresponding to said first number of bits, each group of bits corresponding to a particular bit in said first number of bits, selecting one or more groups of bits based upon a state of said particular bits in said first number of bits, and determining from each selected group of bits at least one bit of said authentication value.

5. The supply item of claim 4 , wherein said first algorithm is a hashing algorithm.

6. The supply item of claim 5 , wherein said preliminary number is an output digest of said hashing algorithm.

7. The supply item of claim 4 , wherein said supply item is an ink jet printhead cartridge.

8. The supply item of claim 4 , wherein said supply item is an electrophotographic cartridge.

9. A supply item including an authentication system, said authentication system configured to perform the acts comprising:

processing an input including at least an identification number assigned to said supply item, using a first algorithm, to generate a preliminary number different from said identification number; and

compressing said preliminary number using a non-hash compression only algorithm, different from said first algorithm, that utilizes said identification number to generate an authentication value for use in authenticating said supply item, said non-hash compression only algorithm comprising a masking operation utilizing said identification number,

wherein said masking process comprises dividing said preliminary number into a number of groups of bits corresponding to a number of bits in said identification number, each group of bits corresponding to a particular bit in said identification number, selecting one or more groups of bits based upon a state of said particular bits in said identification number, and determining from each selected group of bits at least one bit of said authentication value.

10. The supply item of claim 9 , wherein said first algorithm is a hashing algorithm.

11. The supply item of claim 10 , wherein said preliminary number is an output digest of said hashing algorithm.

12. The supply item of claim 9 , wherein said supply item is an ink jet printhead cartridge.

13. The supply item of claim 9 , wherein said supply item is an electrophotographic cartridge.

14. A method of generating an authentication code for a consumable, comprising:

associating a first number with said consumable; processing an input including at least said first number, using a first algorithm, to generate a preliminary number different from said first number: and

compressing said preliminary number using a non-hash compression only algorithm different from said first algorithm, that utilizes said first number to generate an authentication value for use in authenticating said consumable, said non-hash compression only algorithm comprising a masking operation utilizing said first number,

wherein said masking process comprises dividing said preliminary number into a number of groups of bits corresponding to a number of bits in said first number, each group of bits corresponding to a particular bit in said first number, selecting one or more groups of bits based upon a state of said particular bits in said first number, and determining from each selected group of bits at least one bit of said authentication value.

15. The method of claim 14 , wherein said first number is an identification number.

16. The method of claim 14 , wherein said preliminary number is an output digest of a hashing function.

17. A method for authenticating a consumable used by an imaging device, wherein the method comprises supplying an authentication code for comparison with a verifying code, wherein if the verifying code matches the authentication code the consumable is authenticated; and wherein the verifying code is generated by a method comprising:

using a first algorithm to generate a preliminary number different from an identification number; and

compressing said preliminary number using a non-hash compression only algorithm, different from said first algorithm, that utilizes said identification number to generate the verifying code, said non-hash compression only algorithm comprising a masking process using said identification number,

wherein said masking process comprises dividing said preliminary number into a number of groups of bits corresponding to a number of bits in said identification number, each group of bits corresponding to a particular bit in said identification number, selecting one or more groups of bits based upon a state of said particular bits in said identification number, and determining from each selected group of bits at least one bit of said authentication value.

18. The method of claim 17 , wherein said first algorithm is a hashing algorithm.

19. The method of claim 18 , wherein said preliminary number is an output digest of said hashing algorithm.

20. A verifying code for a consumable used by an imaging device and generated by a method, comprising:

processing an input including at least an identification number associated with the consumable, using a first algorithm to generate a preliminary number different from said identification number; and

compressing said preliminary number using a non-hash compression only algorithm, different from said first algorithm, that utilizes said identification number to generate the verifying code, said non-hash compression only algorithm comprising a masking operation utilizing said identification number,

wherein said masking process comprises dividing said preliminary number into a number of groups of bits corresponding to a number of bits in said identification number, each group of bits corresponding to a particular bit in said identification number, selecting one or more groups of bits based upon a state of said particular bits in said identification number, and determining from each selected group of bits at least one bit of said authentication value.

21. The method of claim 20 , wherein said first algorithm is a hashing algorithm.

22. The method of claim 21 , wherein said preliminary number is an output digest of said hashing algorithm.

23. An authentication code for a consumable used by an imaging device, wherein the authentication code matches a verifying code that is generated by a method, comprising:

processing an input including at least an identification number associated with the consumable, using a first algorithm to generate a preliminary number different from said identification number; and

compressing said preliminary number using a non-hash compression only algorithm, different from said first algorithm, that utilizes said identification number to generate the verifying code, said non-hash compression only algorithm comprising a masking operation utilizing said identification number,

wherein said masking process comprises dividing said preliminary number into a number of groups of bits corresponding to a number of bits in said identification number, each group of bits corresponding to a particular bit in said identification number, selecting one or more groups of bits based upon a state of said particular bits in said identification number, and determining from each selected group of bits at least one bit of said authentication value.

24. The method of claim 23 , wherein said first algorithm is a hashing algorithm.

25. The method of claim 24 , wherein said preliminary number is an output digest of said hashing algorithm.

26. A consumable used by an imaging device, wherein memory is associated with the consumable, the memory comprising:

an identification number associated with the consumable; and

an authentication code matching a verifying code generated by a method comprising:

processing an input including at least said identification number, using a first algorithm to generate a preliminary number different from said identification number; and

compressing said preliminary number using a non-hash compression only algorithm, different from said first algorithm, that utilizes said identification number to generate said verifying code, said non-hash compression only algorithm comprises a masking operation using said identification number,

wherein said masking process comprises dividing said preliminary number into a number of groups of bits corresponding to a number of bits in said identification number, each group of bits corresponding to a particular bit in said identification number, selecting one or more groups of bits based upon a state of said particular bits in said identification number, and determining from each selected group of bits at least one bit of said authentication value.

27. The method of claim 26 , wherein said first algorithm is a hashing algorithm.

28. The method of claim 27 , wherein said preliminary number is an output digest of said hashing algorithm.

29. A data structure associated with a consumable used by an imaging device, the data structure comprises:

an identification number associated with the consumable; and

an authentication code matching a verifying code generated by a method comprising:

processing an input including at least said identification number, using a first algorithm to generate a preliminary number different from said identification number; and

compressing said preliminary number using a non-hash compression only algorithm, different from said first algorithm, that utilizes said identification number to generate said verifying code, said non-hash compression only algorithm comprises a masking operation utilizing said identification number,

wherein said masking process comprises dividing said preliminary number into a number of groups of bits corresponding to a number of bits in said identification number, each group of bits corresponding to a particular bit in said identification number, selecting one or more groups of bits based upon a state of said particular bits in said identification number, and determining from each selected group of bits at least one bit of said authentication value.

30. The method of claim 29 , wherein said first algorithm is a hashing algorithm.

31. The method of claim 30 , wherein said preliminary number is an output digest of said hashing algorithm.