ENBD:Extended Network Block Device
ENBD：扩展的网络磁盘设备

Network block device(NBD)is a stable and open source network storage software,which can be used to construct a network storage system based on Linux.Normally network storage system is complex,including miscellaneous modules.But NBD just transmits data over network and lacks the functions of clustering,scalability,special operations required by a network storage system.This paper outlines how to extend NBD to apply for Blue Whale File System.