Can the storage capacity of memories built from unreliable components be determined?

A memory is a device in which information is stored at some time and retrieved at a later time . Let the information be stored in form of bits in registers (memory elements) each of which can store a single bit. The information storage capability of a memory is the number of information bits it stores. Building a memory with information storage capability of k bits with reliable memory elements requires k registers. Such a memory is termed as an irredundant memory. This paper considers the problem of building a memory with memory elements and logic gates which fail according to a known random mechanism. The required minimum redundancy memory in which makes arbitrarily reliable information possible is discussed. For a reliable storage, the information needs to be stored in coded form . To ensure reliability, a correcting circuit is employed which performs error correction and updates the contents of the registers with an estimate of the original codeword.