1 introduction

1.1 processes

• finite set of processes that know each other p_1, \cdots, p_N
• processes are sequential but work independently
• no assumption on the speed of individual processes
• crashed process does not recover
• process is called correct if it does not crash, otherwise it is called faulty
• processes access shared objects through their operations which return replies

1.1.1 wait-freedom

A process gets replies despite the crash of other processes. Operations look sequential from the outside.

1.1.2 register

Has a read and write operation. Initially stores 0, we assume it stores integers.