The primary goal with NFS v4, according to Bill Moffitt, Solaris marketing at Sun Microsystems Inc., is to open up the protocol to a wider group of applications and users by "quickly and securely sharing files over the public Internet."
But better security and wide area network (WAN) performance are not the only changes in NFS v4. Other new features that differentiate it from previous versions include: integrating file locking and mounting in a single protocol; more support for replication and migration; increased support for Windows-based file sharing; and improvements in file sharing over the Internet, such as requiring TCP as a transport, defining a global user identifier name space and enabling operation through firewalls.
Randy Kerns, senior partner at the Evaluator Group, Greenwood Village, Colo., sees file locking as the most compelling improvement of NFS v4. The hard locks in NFS v4 prevent two applications from trying to access the same data, which can lead to data integrity problems. "What hard locks do is make locking more common between NFS and CIFS, which is important for sharing of data between the different protocols," Kerns said.
Moffitt said that the enhancements in NFS v4 are based on user feedback gathered by the Internet Engineering Task Force (IETF), a standards committee that oversees NFS. The IETF is made up of engineers and researchers from Sun, Network Appliance, Hummingbird Communications Ltd., Linux and others that have been working over the years "to figure out which features in NFS need to be fixed," Moffitt said.
NFS v4 is currently available in Sun's Solaris 10 operating system, released in late January. It is also available in Linux environments, and it's worth noting that PolyServe Inc. and Network Appliance are working with University of Michigan's Center for Information Technology Information (CITI) to create an industry standard for implementation of NFS v4 in Linux environments. PolyServe is helping to implement NFS v4 on the server side, while NetApp is assisting with the client-side implementation.
Moffitt stressed that of all the enhancements of NFS v4, being able to quickly share files across the Internet is what sets the protocol apart from previous versions. "NFS v3 mastered file sharing over a network, but version 4 is extending that to the entire world using the Internet," he said.
According to Sun, there are very few users in production with NFS v4 yet, but the company expects this to change when Solaris 10 becomes pervasive. "Most customers will test it for quite a while before rolling out and will need to do OS upgrades … There will be slow adoption over the next year," the spokesperson said.Click here for more of today's news.