  In this paper we survey the various erasure codes which had been proposed and
patented recently, and along the survey we provide introductory tutorial on
many of the essential concepts and readings in erasure and Fountain codes.
Packet erasure is a fundamental characteristic inherent in data storage and
data transmission system. Traditionally replication/ retransmission based
techniques had been employed to deal with packet erasures in such systems.
While the Reed-Solomon (RS) erasure codes had been known for quite some time to
improve system reliability and reduce data redundancy, the high decoding
computation cost of RS codes has offset wider implementation of RS codes.
However recent exponential growth in data traffic and demand for larger data
storage capacity has simmered interest in erasure codes. Recent results have
shown promising results to address the decoding computation complexity and
redundancy tradeoff inherent in erasure codes.
