checking the received bits of the attempted password as they correspond to respective bits of a password stored in tag memory in addition the counter can be adjusted by an amount in relation to how many of the attempted password bits differ from their corresponding bits of the first password this way someone who misses only one bit e g due to interference would be penalized by less than someone who attempts a password at random operations 510 540 560 and 570 can be implemented in different orders according to embodiments one such example is shown in fig6 as flowchart 600 the operations of flowchart 500 600 and others result in the tag having in some embodiments only a limited number of remaining commands it will comply with many examples are now described which tags according to embodiment may implement individually or in combination fig7 a is a diagram 710 contrasting behaviors a rfid tags in the horizontal axis there is shown a number of commands received sequentially from one or more rfid readers in the vertical axis there is shown the remaining number of command compliances a horizontal behavior line 712 shows what a prior art tag does namely according to a comment 714 a tag replies to all commands as long as they are not themselves disabling commands like the kill command the.