With the increasing explosively of data in network,more and more people pay attention to the networked storage ,currently the main technology of networked storage is NAS ( Network Attached Storage )and SAN ( Storage Area Network ). They are different ,and they are not competed but complement ,they are used in different occasion.To reduce the TOC (total of cost),people hope to merges the two technology :design a united storage network,it can supply the virtues and overcome the drawbacks of the NAS and SAN. This paper analysis and discuss the topic.