Patent ID: 7412480

Claim:
A computer-implemented method of a software provider ( 25 ) enabling a software-acquiring entity ( 20 ) to arrive from an existent first signed piece of code ( 11 ), which is executable on a machine, at a second signed piece of code ( 12 , 13 ), which is executable on the machine, both pieces of code ( 11 , 12 , 13 ) having been generated by use of a first software archive generator ( 2 ) under use of generation instructions ( 8 ), comprising the step of: providing to said software-acquiring entity ( 20 ) a difference code ( 4 , 5 ), said difference code comprising the steps necessary to arrive from said first signed piece of code ( 11 ) at said second signed piece of code ( 12 , 13 ), said steps further including instructions to amend said first signed piece of code so that a signature belonging to said second signed piece of code is the same signature for a corresponding second signed piece of code existing at the software provider, said difference code ( 4 , 5 ) is usable at said software-acquiring entity ( 20 ); and amending using said difference code said first signed piece of code ( 11 ) by a second software archive generator ( 7 ) to generate said second signed piece of code ( 12 , 13 ), whereby said second software archive generator ( 7 ) is fed with those generation instructions ( 8 ) that were used by said first software archive generator ( 2 ) for the generation of both pieces of code ( 11 , 12 , 13 ), wherein for more than two nieces of code ( 11 , 12 , 13 ) being stored, the difference code ( 4 , 5 ) is generated only between a subset of said pieces of code ( 11 , 12 , 13 ) and wherein for arriving from the first piece of code ( 11 ) to the second piece of code ( 13 ) several difference codes ( 4 , 5 ) are required, these difference codes ( 4 , 5 ) are merged to a single difference code to be provided to the software-acquiring entity ( 20 ).